Wintrust Financial (WTFC) 10-K 28 Feb 19 2018 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2018	Feb. 26, 2019	Jun. 29, 2018
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2,018
Trading Symbol	WTFC
Entity Registrant Name	WINTRUST FINANCIAL CORP
Entity Central Index Key	1,015,328
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		56,507,442
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Public Float			$ 4,860,291,899

Consolidated Statements Of Cond

Consolidated Statements Of Condition - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Assets
Cash and due from banks	$ 392,142	$ 277,534
Federal funds sold and securities purchased under resale agreements	58	57
Interest bearing deposits with banks	1,099,594	1,063,242
Available-for-sale securities, at fair value	2,126,081	1,803,666
Held-to-maturity securities, at amortized cost ($1.0 billion and $812.5 million fair value at December 31, 2018 and 2017, respectively)	1,067,439	826,449
Trading account securities	1,692	995
Equity securities with readily determinable fair value	34,717	0
Federal Home Loan Bank and Federal Reserve Bank stock	91,354	89,989
Brokerage customer receivables	12,609	26,431
Mortgage loans held-for-sale	264,070	313,592
Loans, net of unearned income	23,820,691	21,640,797
Allowance for loan losses	(152,770)	(137,905)
Net loans	23,667,921	21,502,892
Premises and equipment, net	671,169	621,895
Lease investments, net	233,208	212,335
Accrued interest receivable and other assets	696,707	567,374
Trade date securities receivable	263,523	90,014
Goodwill	573,141	501,884
Other intangible assets	49,424	17,621
Total assets	31,244,849	27,915,970
Deposits:
Non-interest bearing	6,569,880	6,792,497
Interest bearing	19,524,798	16,390,850
Total deposits	26,094,678	23,183,347
Federal Home Loan Bank advances	426,326	559,663
Other borrowings	393,855	266,123
Subordinated notes	139,210	139,088
Junior subordinated debentures	253,566	253,566
Accrued interest payable and other liabilities	669,644	537,244
Total liabilities	27,977,279	24,939,031
Preferred stock, no par value; 20,000,000 shares authorized:
Common stock, no par value; $1.00 stated value; 100,000,000 shares authorized at December 31, 2018 and 2017; 56,518,119 shares issued at December 31, 2018 and 56,068,220 shares issued at December 31, 2017	56,518	56,068
Surplus	1,557,984	1,529,035
Treasury stock, at cost, 110,561 shares at December 31, 2018 and 103,013 shares at December 31, 2017	(5,634)	(4,986)
Retained earnings	1,610,574	1,313,657
Accumulated other comprehensive loss	(76,872)	(41,835)
Total shareholders’ equity	3,267,570	2,976,939
Total liabilities and shareholders’ equity	31,244,849	27,915,970
Series D preferred stock
Preferred stock, no par value; 20,000,000 shares authorized:
Series D - $25 liquidation value; 5,000,000 shares issued and outstanding at December 31, 2018 and December 31, 2017	$ 125,000	$ 125,000

Consolidated Statements Of Co_2

Consolidated Statements Of Condition (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Held-to-maturity securities, fair value	$ 1,036,096	$ 812,516
Preferred stock, authorized (in shares)	20,000,000	20,000,000
Common stock, stated value (in usd per share)	$ 1	$ 1
Common stock, authorized (in shares)	100,000,000	100,000,000
Common stock, issued (in shares)	56,518,119	56,068,220
Treasury stock (in shares)	110,561	103,013
Series D preferred stock
Preferred stock, liquidation value (in usd per share)	$ 25	$ 25
Preferred stock, issued (in shares)	5,000,000	5,000,000
Preferred stock, outstanding (in shares)	5,000,000	5,000,000

Consolidated Statements Of Inco

Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest income
Interest and fees on loans	$ 1,044,502	$ 856,549	$ 726,048
Mortgage loans held-for-sale	15,738	12,332	14,953
Interest bearing deposits with banks	17,090	9,252	4,236
Federal funds sold and securities purchased under resale agreements	1	2	4
Investment securities	87,382	63,315	62,038
Trading account securities	43	25	75
Federal Home Loan Bank and Federal Reserve Bank stock	5,331	4,370	4,287
Brokerage customer receivables	723	623	816
Total interest income	1,170,810	946,468	812,457
Interest expense
Interest on deposits	166,553	83,326	58,409
Interest on Federal Home Loan Bank advances	12,412	8,798	10,886
Interest on other borrowings	8,599	5,370	4,355
Interest on subordinated notes	7,121	7,116	7,111
Interest on junior subordinated debentures	11,222	9,782	9,503
Total interest expense	205,907	114,392	90,264
Net interest income	964,903	832,076	722,193
Provision for credit losses	34,832	29,768	34,084
Net interest income after provision for credit losses	930,071	802,308	688,109
Non-interest income
Mortgage banking	136,990	113,472	128,743
(Losses) gains on investment securities, net	(2,898)	45	7,645
Fees from covered call options	3,519	4,402	11,470
Trading gains (losses), net	11	(845)	91
Operating lease income, net	38,451	29,646	16,441
Other	52,710	56,507	53,812
Total non-interest income	356,150	319,506	325,430
Non-interest expense
Salaries and employee benefits	480,077	430,078	405,158
Equipment	42,949	38,358	37,055
Operating lease equipment depreciation	29,305	24,107	13,259
Occupancy, net	57,814	52,920	50,912
Data processing	35,027	31,495	28,776
Advertising and marketing	41,140	30,830	24,776
Professional fees	32,306	27,835	20,411
Amortization of other intangible assets	4,571	4,401	4,789
FDIC insurance	17,209	16,231	16,065
OREO expenses, net	6,120	3,593	5,187
Other	79,570	71,969	75,297
Total non-interest expense	826,088	731,817	681,685
Income before taxes	460,133	389,997	331,854
Income tax expense	116,967	132,315	124,979
Net income	343,166	257,682	206,875
Preferred stock dividends	8,200	9,778	14,513
Net income applicable to common shares	$ 334,966	$ 247,904	$ 192,362
Net income per common share - Basic (usd per share)	$ 5.95	$ 4.53	$ 3.83
Net income per common share - Diluted (usd per share)	5.86	4.40	3.66
Cash dividends declared per common share (in usd per share)	$ 0.76	$ 0.56	$ 0.48
Weighted average common shares outstanding (in shares)	56,300	54,703	50,278
Dilutive potential common shares (in shares)	908	1,983	3,994
Average common shares and dilutive common shares (in shares)	57,208	56,686	54,272
Wealth management
Non-interest income
Revenue from contracts with customers	$ 90,963	$ 81,766	$ 76,018
Service charges on deposit accounts
Non-interest income
Revenue from contracts with customers	$ 36,404	$ 34,513	$ 31,210

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 343,166	$ 257,682	$ 206,875
Unrealized (losses) gains on available-for-sale securities
Before tax	(27,408)	22,123	(28,932)
Tax effect	7,354	(7,706)	11,378
Net of tax	(20,054)	14,417	(17,554)
Reclassification of net gains on available-for-sale securities included in net income
Before tax	33	45	7,645
Tax effect	(9)	(18)	(3,004)
Net of tax	24	27	4,641
Reclassification of amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale
Before tax	89	1,479	(17,386)
Tax effect	(24)	(585)	6,826
Net of tax	65	894	(10,560)
Net unrealized (losses) gains on available-for-sale securities	(20,143)	13,496	(11,635)
Unrealized (losses) gains on derivative instruments
Before tax	(1,160)	4,958	10,473
Tax effect	310	(1,959)	(4,115)
Net unrealized (losses) gains on derivative instruments	(850)	2,999	6,358
Foreign currency translation adjustment
Before tax	(12,216)	9,446	3,737
Tax effect	3,026	(2,448)	(1,080)
Net foreign currency translation adjustment	(9,190)	6,998	2,657
Total other comprehensive (loss) income	(30,183)	23,493	(2,620)
Comprehensive income	$ 312,983	$ 281,175	$ 204,255

Consolidated Statements Of Chan

Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred stock	Common stock	Surplus	Treasury stock	Retained earnings	Accumulated other comprehensive income (loss)	Series C preferred stock	Series C preferred stockPreferred stock	Series C preferred stockCommon stock	Series C preferred stockSurplus
Balance at beginning of period at Dec. 31, 2015	$ 2,352,274	$ 251,287	$ 48,469	$ 1,190,988	$ (3,973)	$ 928,211	$ (62,708)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	206,875					206,875
Other comprehensive income (loss), net of tax	(2,620)						(2,620)
Cash dividends declared on common stock	(24,055)					(24,055)
Dividends on preferred stock	(14,513)					(14,513)
Stock-based compensation	9,303			9,303
Conversion of Series C Preferred Stock to common stock								$ 0	$ (30)	$ 1	$ 29
Common stock issued for:
New issuance, net of costs	152,911		3,000	149,911
Exercise of stock options and warrants	11,228		329	11,276	(377)
Restricted stock awards	1		98	142	(239)
Employee stock purchase plan	2,637		56	2,581
Director compensation plan	1,576		25	1,551
Balance at end of period at Dec. 31, 2016	2,695,617	251,257	51,978	1,365,781	(4,589)	1,096,518	(65,328)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	257,682					257,682
Other comprehensive income (loss), net of tax	23,493						23,493
Cash dividends declared on common stock	(30,765)					(30,765)
Dividends on preferred stock	(9,778)					(9,778)
Stock-based compensation	12,858			12,858
Conversion of Series C Preferred Stock to common stock								$ 0	$ (126,257)	$ 3,121	$ 123,136
Common stock issued for:
Exercise of stock options and warrants	24,074		813	23,261	0
Restricted stock awards	(397)		88	(88)	(397)
Employee stock purchase plan	2,530		36	2,494
Director compensation plan	1,625		32	1,593
Balance at end of period at Dec. 31, 2017	2,976,939	125,000	56,068	1,529,035	(4,986)	1,313,657	(41,835)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	(2,974)					2,974	(2,974)
Balance at beginning of period at Dec. 31, 2017	2,976,939	125,000	56,068	1,529,035	(4,986)	1,313,657	(41,835)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	343,166					343,166
Other comprehensive income (loss), net of tax	(30,183)						(30,183)
Cash dividends declared on common stock	(42,787)					(42,787)
Dividends on preferred stock	(8,200)					(8,200)
Stock-based compensation	13,496			13,496
Common stock issued for:
Exercise of stock options and warrants	11,466		299	11,359	(192)
Restricted stock awards	(456)		101	(101)	(456)
Employee stock purchase plan	2,523		31	2,492
Director compensation plan	1,722		19	1,703
Balance at end of period at Dec. 31, 2018	3,267,570	$ 125,000	$ 56,518	$ 1,557,984	$ (5,634)	1,610,574	(76,872)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment from the adoption of ASUs | ASU 2016-01	(1,880)					1,880	$ (1,880)
Cumulative effect adjustment from the adoption of ASUs | ASU 2017-12	$ (116)					$ (116)

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Activities:
Net income	$ 343,166	$ 257,682	$ 206,875
Adjustments to reconcile net income to net cash provided by operating activities
Provision for credit losses	34,832	29,768	34,084
Depreciation, amortization and accretion, net	67,665	63,107	53,148
Deferred income tax expense	55,224	63,243	6,676
Stock-based compensation expense	13,496	12,858	9,303
Net amortization of premium on securities	7,411	6,098	5,646
Accretion of discounts on loans	(20,318)	(22,784)	(35,571)
Mortgage servicing rights fair value change, net	5,370	1,857	3,405
Originations and purchases of mortgage loans held-for-sale	(3,955,438)	(3,692,085)	(4,386,339)
Proceeds from sales of mortgage loans held-for-sale	4,076,887	3,869,137	4,468,984
BOLI income	(5,448)	(3,524)	(3,594)
(Increase) decrease in trading securities, net	(697)	994	(1,541)
Net decrease (increase) in brokerage customer receivables	13,822	(1,250)	2,450
Gains on mortgage loans sold	(104,998)	(88,699)	(112,981)
Losses (gains) on investment securities, net, and dividend reinvestment on equity securities	2,000	(45)	(7,645)
Gains on early extinguishment of debt, net	0	0	(3,588)
Losses (gains) on sales of premises and equipment, net	64	(192)	(305)
Net losses on sales and fair value adjustments of other real estate owned	4,664	639	1,381
Gain on termination of loss share agreements with the FDIC	0	(385)	0
Increase in accrued interest receivable and other assets, net	(133,519)	(126,583)	(43,953)
(Decrease) increase in accrued interest payable and other liabilities, net	(27,001)	31,790	114,531
Net Cash Provided by Operating Activities	377,182	401,626	310,966
Investing Activities:
Proceeds from maturities and calls of available-for-sale securities	352,683	276,097	1,247,894
Proceeds from maturities and calls of held-to-maturity securities	11,129	108,943	735,036
Proceeds from sales of available-for-sale securities	214,196	344,674	2,194,278
Proceeds from sales of equity securities with readily determinable fair value	1,895	0	0
Proceeds from sales and capital distributions of equity securities without readily determinable fair value	1,324	0	0
Purchases of available-for-sale securities	(1,095,375)	(774,041)	(3,398,640)
Purchases of held-to-maturity securities	(253,129)	(301,909)	(486,696)
Purchases of equity securities without readily determinable fair value	(4,592)	0	0
(Purchase) redemption of Federal Home Loan Bank and Federal Reserve Bank stock, net	(1,365)	43,505	(31,913)
Distributions from investments in partnerships, net	3,409	512	339
Net cash paid in business combinations	(53,871)	(284)	(613,619)
Proceeds from sales of other real estate owned	19,375	18,742	38,367
Proceeds (paid to) received from the FDIC related to reimbursements on covered assets	0	(15,411)	1,207
Net increase in interest-bearing deposits with banks	(15,988)	(81,621)	(366,591)
Net increase in loans	(1,883,354)	(1,863,245)	(1,779,905)
Redemption of BOLI	8,438	0	1,840
Purchases of premises and equipment, net	(68,273)	(59,194)	(33,923)
Net Cash Used for Investing Activities	(2,763,498)	(2,303,232)	(2,492,326)
Financing Activities:
Increase in deposit accounts	2,547,399	1,524,848	2,769,022
Increase (decrease) in subordinated notes and other borrowings, net	137,257	(4,888)	(3,405)
(Decrease) increase in Federal Home Loan Bank advances, net	(147,999)	403,000	(707,594)
Cash payments to settle contingent consideration liabilities recognized in business combinations	0	(1,097)	(1,273)
Proceeds from the issuance of common stock, net	0	0	152,911
Redemption of junior subordinated debentures, net	0	0	(10,695)
Issuance of common shares resulting from exercise of stock options, employee stock purchase plan and conversion of common stock warrants	15,903	28,229	15,828
Common stock repurchases for tax withholdings related to stock-based compensation	(648)	(397)	(616)
Dividends paid	(50,987)	(40,543)	(38,568)
Net Cash Provided by Financing Activities	2,500,925	1,909,152	2,175,610
Net Increase (Decrease) in Cash and Cash Equivalents	114,609	7,546	(5,750)
Cash and Cash Equivalents at Beginning of Period	277,591	270,045	275,795
Cash and Cash Equivalents at End of Period	392,200	277,591	270,045
Cash paid during the year for:
Interest	197,911	112,783	91,390
Income taxes, net	69,118	76,812	94,888
Business combinations and asset acquisitions:
Fair value of assets acquired, including cash and cash equivalents	485,368	1,022	882,865
Value ascribed to goodwill and other intangible assets	109,548	999	27,083
Fair value of liabilities assumed	423,234	738	259,631
Non-cash activities
Transfer to other real estate owned from loans	7,936	15,013	13,352
Common stock issued for acquisitions	$ 0	$ 0	$ 0

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies The accounting and reporting policies of Wintrust Financial Corporation (“Wintrust” or the “Company”) and its subsidiaries conform to generally accepted accounting principles in the United States and prevailing practices of the banking industry. In the preparation of the consolidated financial statements, management is required to make certain estimates and assumptions that affect the reported amounts contained in the consolidated financial statements. Management believes that the estimates made are reasonable; however, changes in estimates may be required if economic or other conditions change beyond management’s expectations. Reclassifications of certain prior year amounts have been made to conform to the current year presentation. The following is a summary of the Company’s significant accounting policies. Principles of Consolidation The consolidated financial statements of Wintrust include the accounts of the Company and its subsidiaries. All significant intercompany accounts and transactions have been eliminated in the consolidated financial statements. Earnings per Share Basic earnings per share is computed by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted earnings per share reflects the potential dilution that would occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company. The weighted-average number of common shares outstanding is increased by the assumed conversion of outstanding convertible preferred stock shares from the beginning of the year or date of issuance, if later, and the number of common shares that would be issued assuming the exercise of stock options, the issuance of restricted shares and stock warrants using the treasury stock method. The adjustments to the weighted-average common shares outstanding are only made when such adjustments will dilute earnings per common share. Net income applicable to common shares used in the diluted earnings per share calculation can be affected by the conversion of the Company's preferred stock. Where the effect of this conversion would reduce the loss per share or increase the income per share, net income applicable to common shares is not adjusted by the associated preferred dividends. Business Combinations The Company accounts for business combinations under the acquisition method of accounting in accordance with ASC 805, “Business Combinations” (“ASC 805”) when it obtains control of a business. When determining whether a business has been acquired, the Company first evaluates whether substantially all of the fair value of the gross assets acquired are concentrated in a single identifiable asset or a group of similar identifiable assets. If concentrated in such a manner, the set of assets and activities is not a business. If not concentrated in such a manner, the Company assesses whether the set meets the definition of a business by containing inputs, outputs and at least one substantive process. If the set represents a business, the Company recognizes the fair value of the assets acquired and liabilities assumed, immediately expenses transaction costs and accounts for restructuring plans separately from the business combination. There is no separate recognition of the acquired allowance for loan losses on the acquirer’s balance sheet as credit related factors are incorporated directly into the fair value of the loans recorded at the acquisition date. The excess of the cost of the acquisition over the fair value of the net tangible and intangible assets acquired is recorded as goodwill. Alternatively, a gain is recorded equal to the amount by which the fair value of assets purchased exceeds the fair value of liabilities assumed and consideration paid. If the set of assets and activities do not constitute a business, the transaction is accounted for as an asset acquisition. The cost of a group of assets acquired is allocated to the individual assets acquired or liabilities assumed based on the relative fair value and does not result in the recognition of goodwill. Generally, any excess of the cost of the transaction over the fair value of the individual assets acquired or liabilities assumed, or, in contrast, any excess of the fair value of the individual assets acquired or liabilities assumed over the cost of the transaction, should be allocated on a relative fair value basis. Certain "non-qualifying" assets are excluded from this allocation, and are recognized at the individual asset's fair value. Results of operations of the acquired business are included in the income statement from the effective date of acquisition. Subsequent adjustments to provisional amounts that are identified in reporting periods after the acquisition date of the business combination and asset acquisitions are recognized in the reporting period in which the adjustment amounts are determined. Cash Equivalents For purposes of the consolidated statements of cash flows, Wintrust considers cash on hand, cash items in the process of collection, non-interest bearing amounts due from correspondent banks, federal funds sold and securities purchased under resale agreements with original maturities of three months or less, to be cash equivalents. Investment Securities The Company classifies debt and equity securities upon purchase in one of five categories: trading, held-to-maturity debt securities, available-for-sale debt securities, equity securities with a readily determinable fair value or equity securities without a readily determinable fair value. Debt and equity securities held for resale are classified as trading securities. Debt securities for which the Company has the ability and positive intent to hold until maturity are classified as held-to-maturity. All other debt securities are classified as available-for-sale as they may be sold prior to maturity in response to changes in the Company’s interest rate risk profile, funding needs, demand for collateralized deposits by public entities or other reasons. Equity securities are classified based upon whether a readily determinable fair value exists on such security. The fair value of an equity security is readily determinable if it meets certain conditions, including whether sales prices or bid-ask quotes are currently available on certain securities exchanges; traded only in a foreign market that is of a breadth and scope comparable to one of the U.S. markets; or the security is an investment in a mutual fund or similar structure with a fair value per share or unit that is determined and published, and is the basis for current transactions. Held-to-maturity debt securities are stated at amortized cost, which represents actual cost adjusted for premium amortization and discount accretion using methods that approximate the effective interest method. Available-for-sale debt securities are stated at fair value, with unrealized gains and losses, net of related taxes, included in shareholders’ equity as a separate component of other comprehensive income. Trading account securities and equity securities with a readily determinable fair value are stated at fair value. Realized and unrealized gains and losses from sales and fair value adjustments are included in other non-interest income. Equity securities without a readily determinable fair value are stated at either a calculated net asset value per share, if available, or the cost of the security minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar instrument of the same issuer. Subsequent to classification at the time of purchase, the Company may transfer debt securities between trading, held-to-maturity, or available-for-sale. For debt securities transferred to trading, the current unrealized gain or loss at the date of transfer, net of related taxes, is immediately recognized in earnings. Debt securities transferred from trading to either held-to-maturity or available-for-sale has already recognized any unrealized gain or loss into earnings and this amount is not reversed. Unrealized gains or losses, net related taxes, for available-for-sale debt securities transferred to held-to-maturity remains as a separate component of other comprehensive income and an offsetting discount included in the amortized cost of the held-to-maturity debt security. These amounts are amortized over the remaining life of the debt security in equal and offsetting amounts. Unrealized gains or losses for held-to-maturity debt securities transferred to available-for-sale are recognized at the transfer date as a separate component of other comprehensive income, net of related taxes. Declines in the fair value of held-to-maturity and available-for-sale debt investment securities (with certain exceptions for debt securities noted below) that are deemed to be other-than-temporary are charged to earnings as a realized loss, and a new cost basis for the securities is established. In evaluating other-than-temporary impairment, management considers the length of time and extent to which the fair value has been less than cost, the financial condition and near-term prospects of the issuer, and the intent and ability of the Company to retain its investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value in the near term. Declines in the fair value of debt securities below amortized cost are deemed to be other-than-temporary in circumstances where: (1) the Company has the intent to sell a security; (2) it is more likely than not that the Company will be required to sell the debt security before recovery of its amortized cost basis; or (3) the Company does not expect to recover the entire amortized cost basis of the debt security. If the Company intends to sell a debt security or if it is more likely than not that the Company will be required to sell the debt security before recovery, an other-than-temporary impairment write-down is recognized in earnings equal to the difference between the debt security’s amortized cost basis and its fair value. If an entity does not intend to sell the debt security or it is not more likely than not that it will be required to sell the debt security before recovery, the other-than-temporary impairment write-down is separated into an amount representing credit loss, which is recognized in earnings, and an amount related to all other factors, which is recognized in other comprehensive income. Interest and dividends, including amortization of premiums and accretion of discounts, are recognized as interest income when earned. Realized gains and losses on sales (using the specific identification method), unrealized gains and losses on equity securities and declines in value judged to be other-than-temporary are included in non-interest income. FHLB and FRB Stock Investments in FHLB and FRB stock are restricted as to redemption and are carried at cost. Securities Purchased Under Resale Agreements and Securities Sold Under Repurchase Agreements Securities purchased under resale agreements and securities sold under repurchase agreements are generally treated as collateralized financing transactions and are recorded at the amount at which the securities were acquired or sold plus accrued interest. Securities, consisting of U.S. Treasury, U.S. Government agency and mortgage-backed securities, pledged as collateral under these financing arrangements cannot be sold by the secured party. The fair value of collateral either received from or provided to a third party is monitored and additional collateral is obtained or requested to be returned as deemed appropriate. Brokerage Customer Receivables The Company, under an agreement with an out-sourced securities clearing firm, extends credit to its brokerage customers to finance their purchases of securities on margin. The Company receives income from interest charged on such extensions of credit. Brokerage customer receivables represent amounts due on margin balances. Securities owned by customers are held as collateral for these receivables. Mortgage Loans Held-for-Sale Mortgage loans are classified as held-for-sale when originated or acquired with the intent to sell the loan into the secondary market. ASC 825, “Financial Instruments” provides entities with an option to report selected financial assets and liabilities at fair value. Mortgage loans classified as held-for-sale are measured at fair value which is determined by reference to investor prices for loan products with similar characteristics. Changes in fair value are recognized in mortgage banking revenue. Market conditions or other developments may change management’s intent with respect to the disposition of these loans and loans previously classified as mortgage loans held-for-sale may be reclassified to the loans held-for-investment portfolio, with the balance transferred continuing to be carried at fair value. Loans and Leases, Allowance for Loan Losses, Allowance for Covered Loan Losses and Allowance for Losses on Lending-Related Commitments Loans are generally reported at the principal amount outstanding, net of unearned income. Interest income is recognized when earned. Loan origination fees and certain direct origination costs are deferred and amortized over the expected life of the loan as an adjustment to the yield using methods that approximate the effective interest method. Finance charges on premium finance receivables are earned over the term of the loan, using a method which approximates the effective yield method. Leases classified as capital leases are included within lease loans for financial statement purposes. Capital leases are stated as the sum of remaining minimum lease payments from lessees plus estimated residual values less unearned lease income. Unearned lease income on capital leases is recognized over the term of the leases using the effective interest method. Interest income is not accrued on loans where management has determined that the borrowers may be unable to meet contractual principal and/or interest obligations, or where interest or principal is 90 days or more past due, unless the loans are adequately secured and in the process of collection. Cash receipts on non-accrual loans are generally applied to the principal balance until the remaining balance is considered collectible, at which time interest income may be recognized when received. The Company maintains its allowance for loan losses at a level believed appropriate by management to absorb probable losses inherent in the loan portfolio and is based on the size and current risk characteristics of the loan portfolio. Determination of the allowance is inherently subjective as it requires significant estimates, including the amounts and timing of expected future cash flows on impaired loans, estimated losses on pools of homogeneous loans based on the average historical loss experience, and qualitative considerations. The allowance for loan losses includes the following components: 1) specific reserves on impaired loans, 2) a general reserve based upon historical loss experience and 3) qualitative factors to adjust the historical loss experience used, if deemed necessary. If a loan is impaired, the Company analyzes the loan for purposes of calculating our specific impairment reserves. Loans with a credit risk rating of a 6 through 9 are reviewed to determine if (a) an amount is deemed uncollectible (a charge-off) or (b) it is probable that the Company will be unable to collect amounts due in accordance with the original contractual terms of the loan (an impaired loan). If a loan is impaired, the carrying amount of the loan is compared to the expected payments to be received, discounted at the loan’s original rate, or for collateral dependent loans, to the fair value of the collateral less the estimated cost to sell. Any shortfall is recorded as a specific reserve. For loans that are not considered impaired loans, a general reserve is established based on historical loss experience, adjusted for certain qualitative factors, related to the type of loan collateral, if any, and the assigned credit risk rating. Such qualitative factors assessed by management include the following: • an assessment of internally-evaluated problem loans and historical loss experience; • changes in the composition of the loan portfolio, changes in historical loss experience; • changes in lending policies and procedures, including underwriting standards and collections, charge-off and recovery practices; • changes in experience, ability and depth of lending management and staff; • changes in national and local economic and business conditions and developments, including the condition of various market segments; • changes in the volume and severity of past due and classified loans and trends in the volume of non-accrual loans, TDRs and other loan modifications; • changes in the quality of the Company’s loan review system; • changes in the underlying collateral for collateral dependent loans; and • the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the bank’s existing portfolio. All such estimates and considerations may be susceptible to significant change. Loan losses are charged off against the allowance, while recoveries are credited to the allowance. A provision for credit losses is charged to income based on management’s periodic evaluation of the factors previously mentioned, as well as other pertinent factors. Evaluations are conducted at least quarterly and more frequently if deemed necessary. Under accounting guidance applicable to loans acquired with evidence of credit quality deterioration since origination, the excess of cash flows expected at acquisition over the estimated fair value is referred to as the accretable yield and is recognized in interest income over the remaining estimated life of the loans, using the effective-interest method. The difference between contractually required payments at acquisition and the cash flows expected to be collected at acquisition is referred to as the nonaccretable difference. Changes in the expected cash flows from the date of acquisition will either impact the accretable yield or result in a charge to the provision for credit losses. Subsequent decreases to expected principal cash flows will result in a charge to provision for credit losses and a corresponding increase to allowance for loan losses. Subsequent increases in expected principal cash flows will result in recovery of any previously recorded allowance for loan losses, to the extent applicable, and a reclassification from nonaccretable difference to accretable yield for any remaining increase. All changes in expected interest cash flows, including the impact of prepayments, will result in reclassifications to/from nonaccretable differences. In estimating expected losses, the Company evaluates loans for impairment in accordance ASC 310, “Receivables.” A loan is considered impaired when, based on current information and events, it is probable that a creditor will be unable to collect all amounts due pursuant to the contractual terms of the loan. Impaired loans include non-accrual loans, restructured loans or loans with principal and/or interest at risk, even if the loan is current with all payments of principal and interest. Impairment is measured by estimating the fair value of the loan based on the present value of expected cash flows, the market price of the loan, or the fair value of the underlying collateral less costs to sell. If the estimated fair value of the loan is less than the recorded book value, a valuation allowance is established as a component of the allowance for loan losses. For TDRs in which impairment is calculated by the present value of future cash flows, the Company records interest income representing the decrease in impairment resulting from the passage of time during the respective period, which differs from interest income from contractually required interest on these specific loans. The Company also maintains an allowance for lending-related commitments, specifically unfunded loan commitments and letters of credit, to provide for the risk of loss inherent in these arrangements. The allowance is computed using a methodology similar to that used to determine the allowance for loan losses. This allowance is included in other liabilities on the statement of condition while the corresponding provision for these losses is recorded as a component of the provision for credit losses. Mortgage Servicing Rights MSRs are recorded in the Consolidated Statements of Condition at fair value in accordance with ASC 860, “Transfers and Servicing.” The Company originates mortgage loans for sale to the secondary market. Certain loans are originated and sold with servicing rights retained. MSRs associated with loans originated and sold, where servicing is retained, are capitalized at the time of sale at fair value based on the future net cash flows expected to be realized for performing the servicing activities, and included in other assets in the Consolidated Statements of Condition. The change in the fair value of MSRs is recorded as a component of mortgage banking revenue in non-interest income in the Consolidated Statements of Income. The Company measures the fair value of MSRs by stratifying the servicing rights into pools based on homogenous characteristics, such as product type and interest rate. The fair value of each servicing rights pool is calculated based on the present value of estimated future cash flows using a discount rate commensurate with the risk associated with that pool, given current market conditions. Estimates of fair value include assumptions about prepayment speeds, interest rates and other factors which are subject to change over time. Changes in these underlying assumptions could cause the fair value of MSRs to change significantly in the future. Lease Investments The Company’s investments in equipment and other assets held on operating leases are reported as lease investments, net. Rental income on operating leases is recognized as income over the lease term on a straight-line basis. Equipment and other assets held on operating leases is stated at cost less accumulated depreciation. Depreciation of the cost of the assets held on operating leases, less any residual value, is computed using the straight-line method over the term of the leases, which is generally seven years or less. Premises and Equipment Premises and equipment, including leasehold improvements, are stated at cost less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives of the related assets. Useful lives range from two to 15 years for furniture, fixtures and equipment, two to five years for software and computer-related equipment and seven to 39 years for buildings and improvements. Land improvements are amortized over a period of 15 years and leasehold improvements are amortized over the shorter of the useful life of the improvement or the term of the respective lease including any lease renewals deemed to be reasonably assured. Land and antique furnishings and artwork are not subject to depreciation. Expenditures for major additions and improvements are capitalized, and maintenance and repairs are charged to expense as incurred. Internal costs related to the configuration and installation of new software and the modification of existing software that provides additional functionality are capitalized. Long-lived depreciable assets are evaluated periodically for impairment when events or changes in circumstances indicate the carrying amount may not be recoverable. Impairment exists when the expected undiscounted future cash flows of a long-lived asset are less than its carrying value. In that event, a loss is recognized for the difference between the carrying value and the estimated fair value of the asset based on a quoted market price, if applicable, or a discounted cash flow analysis. Impairment losses are recognized in other non-interest expense. FDIC Loss Share Asset (Liability) In conjunction with FDIC-assisted transactions, the Company entered into loss share agreements with the FDIC. These agreements covered losses incurred with respect to loans, foreclosed real estate and certain other assets. The loss share assets and liabilities were measured separately from the loan portfolios because they were not contractually embedded in the loans and were not transferable with the loans should the Company choose to dispose of them. Fair values at the acquisition dates were estimated based on projected cash flows available for loss-share based on the credit adjustments estimated for each loan pool and the loss share percentages. The loss share assets and liabilities were recorded as FDIC indemnification assets and other liabilities on the Consolidated Statements of Condition. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses reduced FDIC loss share assets or increased FDIC loss share liabilities. Reductions to expected losses, to the extent such reductions to expected losses were the result of an improvement to the actual or expected cash flows from the covered assets, also reduced FDIC loss share assets or increased FDIC loss share liabilities. In accordance with certain clawback provisions, the Company was required to reimburse the FDIC when actual losses were less than certain thresholds established for each loss share agreement. The balance of these estimated reimbursements and any related amortization were adjusted periodically for changes in the expected losses on covered assets. On the Consolidated Statements of Condition, estimated reimbursements from clawback provisions were recorded as a reduction to FDIC loss share assets or an increase to FDIC loss share liabilities. Although these assets and liabilities were contractual receivables from and payables to the FDIC, there were no contractual interest rates. Additional expected losses, to the extent such expected losses resulted in the recognition of an allowance for loan losses, increased FDIC loss share assets or reduced FDIC loss share liabilities. The corresponding amortization or accretion was recorded as a component of non-interest income on the Consolidated Statements of Income. On October 16, 2017, the Company entered into agreements with the FDIC that terminated all existing loss share agreements with the FDIC. See Note 7, "Business Combinations," for further discussion of the termination of FDIC loss share agreements. Other Real Estate Owned Other real estate owned is comprised of real estate acquired in partial or full satisfaction of loans and is included in other assets. Other real estate owned is recorded at its estimated fair value less estimated selling costs at the date of transfer. Any excess of the related loan balance over the fair value less expected selling costs is charged to the allowance for loan losses. In contrast, any excess of the fair value less expected selling costs over the related loan balance is recorded as a recovery of prior charge-offs on the loan and, if any portion of the excess exceeds prior charge-offs, as an increase to earnings. Subsequent changes in value are reported as adjustments to the carrying amount and are recorded in other non-interest expense. Gains and losses upon sale, if any, are also charged to other non-interest expense. At December 31, 2018 and 2017, other real estate owned, excluding covered other real estate owned, totaled $24.8 million and $40.6 million , respectively. Goodwill and Other Intangible Assets Goodwill represents the excess of the cost of an acquisition over the fair value of net assets acquired. Other intangible assets represent purchased assets that also lack physical substance but can be distinguished from goodwill because of contractual or other legal rights or because the asset is capable of being sold or exchanged either on its own or in combination with a related contract, asset or liability. In accordance with accounting standards, goodwill is not amortized, but rather is tested for impairment on an annual basis or more frequently when events warrant, using a qualitative or quantitative approach. Intangible assets which have finite lives are amortized over their estimated useful lives and also are subject to impairment testing. Intangible assets which have indefinite lives are evaluated each reporting date to determine whether events and circumstances continue to support an indefinite useful life. If an indefinite useful life can no longer be supported for such asset, the intangible asset will begin amortization over the estimated useful life at that point of time. If an indefinite useful life can be supported, the asset is not amortized, but rather is tested for impairment on an annual basis or more frequently when events warrant, using a qualitative or quantitative approach. All of the Company’s intangible assets with finite lives are amortized over varying periods not exceeding twenty years. Bank-Owned Life Insurance ("BOLI") The Company maintains BOLI on certain executives. BOLI balances are recorded at their cash surrender values and are included in other assets. Changes in the cash surrender values are included in non-interest income. At December 31, 2018 and 2017 , BOLI totaled $147.9 million and $145.9 million , respectively. Derivative Instruments The Company enters into derivative transactions principally to protect against the risk of adverse price or interest rate movements on the future cash flows or the value of certain assets and liabilities. The Company is also required to recognize certain contracts and commitments, including certain commitments to fund mortgage loans held-for-sale, as derivatives when the characteristics of those contracts and commitments meet the definition of a derivative. The Company accounts for derivatives in accordance with ASC 815, “Derivatives and Hedging,” which requires that all derivative instruments be recorded in the statement of condition at fair value. The accounting for changes in the fair value of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and further, on the type of hedging relationship. Derivative instruments designated in a hedge relationship to mitigate exposure to changes in the fair value of an asset or liability attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Derivative instruments designated in a hedge relationship to mitigate exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Formal documentation of the relationship between a derivative instrument and a hedged asset or liability, as well as the risk-management objective and strategy for undertaking each hedge transaction and an assessment of effectiveness is required at inception to apply hedge accounting. In addition, formal documentation of ongoing effectiveness testing is required to maintain hedge accounting. Fair value hedges are accounted for by recording the changes in the fair value of the derivative instrument and the changes in the fair value related to the risk being hedged of the hedged asset or liability on the statement of condition with corresponding offsets recorded in the income statement. The adjustment to the hedged asset or liability is included in the basis of the hedged item, while the fair value of the derivative is recorded as a freestanding asset or liability. Actual cash receipts or payments and related amounts accrued during the period on derivatives included in a fair value hedge relationship are recorded as adjustments to the interest income or expense recorded on the hedged asset or liability. Cash flow hedges are accounted for by recording the changes in the fair value of the derivative instrument on the statement of condition as either a freestanding asset or liability, with a corresponding offset recorded in other comprehensive income within shareholders’ equity, net of deferred taxes. Amounts are reclassified from accumulated other comprehensive income to interest expense in the period or periods the hedged forecasted transaction aff

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Leases In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842),” to improve transparency and comparability across entities regarding leasing arrangements. This ASU requires the recognition of a separate lease liability representing the required discounted lease payments over the lease term and a separate lease asset representing the right to use the underlying asset during the same lease term. Further, this ASU provides clarification regarding the identification of certain components of contracts that would represent a lease as well as requires additional disclosures to the notes of the financial statements. Additionally, in January 2018, the FASB issued ASU No. 2018-01, "Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842," to permit an entity to elect an optional practical expedient to not evaluate under Topic 842 land easements that exist or expired before the entity's adoption of Topic 842 and that were not previously accounted for as leases under existing accounting guidance. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach, including the option to apply certain practical expedients. The FASB has continued to issue various updates to clarify and improve specific areas of ASU No. 2016-02. In July 2018, the FASB issued ASU No. 2018-10, “Codification Improvements to Topic 842, Leases,” to clarify the implementation guidance within ASU No. 2016-02 surrounding narrow aspects of Topic 842, including lessee reassessment of lease classifications, the rate implicit in a lease, lessor reassessment of lease terms and purchase options and variable lease payments that depend on an index or a rate. Also, in July 2018, the FASB issued ASU No. 2018-11, “Leases (Topic 842): Targeted Improvements,” to clarify the implementation guidance within ASU No. 2016-02 surrounding comparative period reporting requirements for initial adoption as well as separating lease and non-lease components in a contract and allocating consideration in the contract to the separate components. Also, in December 2018, the FASB issued ASU No. 2018-20, “Leases (Topic 842): Narrow-Scope Improvements for Lessors,” to clarify the implementation guidance within ASU No. 2016-02 surrounding specific aspects of lessor accounting. Like ASU No. 2016-02, this guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. For leasing arrangements in which the Company is a lessee, the Company will primarily recognize separate lease liabilities and right to use assets related to certain banking facilities under operating lease agreements . Other leasing arrangements in which the Company will recognize separate lease liabilities and right to use assets include the use of signage related to certain sponsorships and other agreements, and certain automatic teller machines. The impact of adoption on the financial statements primarily includes the following: • The Company expects to utilize the following transition elections and practical expedients: ◦ Optional transition method to apply the new guidance at the date of adoption (i.e. January 1, 2019) and continue applying current lease accounting guidance for comparative periods (i.e. fiscal years 2018 and 2017). ◦ For lessee arrangements of certain banking facilities, the Company expects to elect the practical expedient to not separate non-lease components from lease components and instead to account for each separate lease and non-lease component as a single lease component. ◦ A package of practical expedients applied to leases existing prior to the effective date that must all be elected together and allow a Company to not reassess: ▪ whether any expiring or existing contracts are or contain a lease; ▪ lease classification for any expired or existing leases; and ▪ whether initial direct costs for any expired or existing leases qualify for capitalization. ◦ A practical expedient that will permit an entity to continue applying its current policy for accounting for expired or existing land easements. ◦ An accounting policy election for short-term leases (i.e. terms of 12 months or less with no purchase option expected to be exercised) to apply accounting similar to ASC 840, specifically to not recognize separate lease liabilities and right to use assets . • The Company expects to recognize at the effective date a right of use asset on the Consolidated Statements of Condition between $150.0 million and $190.0 million . Allowance for Credit Losses In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” to replace the current incurred loss methodology for recognizing credit losses, which delays recognition until it is probable a loss has been incurred, with a methodology that reflects an estimate of all expected credit losses and considers additional reasonable and supportable forecasted information when determining credit loss estimates. This impacts the calculation of an allowance for credit losses for all financial assets measured under the amortized cost basis, including held-to-maturity debt securities and PCI loans at the time of and subsequent to acquisition. Additionally, credit losses related to available-for-sale debt securities would be recorded through the allowance for credit losses and not as a direct adjustment to the amortized cost of the securities. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. The FASB has continued to issue various updates to clarify and improve specific areas of ASU No. 2016-13. In November 2018, the FASB issued ASU No. 2018-19, “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” to clarify the implementation guidance within ASU No. 2016-13 surrounding narrow aspects of Topic 326, including the impact of the guidance on operating lease receivables. Like ASU No. 2016-13, this guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. The Company is currently evaluating the impact of adopting this new guidance on the consolidated financial statements as well as the impact on current systems and processes. Specifically, the Company has established a committee consisting of individuals from the various areas of the Company tasked with transitioning to the new requirements. At this time, the Company is finalizing potential accounting policy elections and modeling methodologies for estimating expected credit losses using reasonable and supportable forecast information. Additionally, the Company is utilizing certain historical data and a previously selected platform to build, store, execute and determine the financial impact. Controls and processes are also being designed for the continued implementation process and after the effective date. Goodwill In January 2017, the FASB issued ASU No. 2017-04, “Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment,” to simplify the subsequent measurement of goodwill. When the carrying amount of a reporting unit exceeds its fair value, an entity would no longer be required to determine goodwill impairment by assigning the fair value of a reporting unit to all of its assets and liabilities as if that reporting unit was acquired in a business combination. Goodwill impairment would be recognized according to the excess of the carrying amount of the reporting unit over the calculated fair value of such unit. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied under a prospective approach. The Company does not expect this guidance to have a material impact on the Company's consolidated financial statements. Amortization of Premium on Certain Debt Securities In March 2017, the FASB issued ASU No. 2017-08, “Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities,” to amend the amortization period for certain purchased callable debt securities held at a premium. The amortization period for such securities will be shortened to the earliest call date. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. Early adoption is permitted as of the beginning of an annual period that has not been issued or made available for issuance. The Company did not early adopt this guidance as of January 1, 2018. The Company has evaluated adoption of this guidance and determined it will not have a material impact on the consolidated financial statements. Fair Value Measurement In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirement for Fair Value Measurement,” to modify disclosure requirements on fair value measurements and inputs. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied prospectively or retrospectively depending upon the disclosure requirement. Early adoption is permitted. The Company does not expect this guidance to have a material impact on the Company's consolidated financial statements. Intangibles In August 2018, the FASB issued ASU No. 2018-15, “Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract,” to align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with similar requirements related to implementation costs incurred to develop or obtain internal-use software. In addition, the amendment requires any capitalized implementation costs related to a hosting arrangement to be expensed over the term of the hosting arrangement. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. Early adoption is permitted, including adoption in any interim period. The Company is currently evaluating the impact of adopting this new guidance on the consolidated financial statements.

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities A summary of the available-for-sale and held-to-maturity securities portfolios presenting carrying amounts and gross unrealized gains and losses as of December 31, 2018 and 2017 is as follows: December 31, 2018 December 31, 2017 (Dollars in thousands) Amortized Cost Gross unrealized gains Gross unrealized losses Fair Value Amortized Cost Gross unrealized gains Gross unrealized losses Fair Value Available-for-sale securities U.S. Treasury $ 126,199 $ 391 $ (186 ) $ 126,404 $ 144,904 $ — $ (1,082 ) $ 143,822 U.S. Government agencies 139,420 917 (30 ) 140,307 157,638 2 (725 ) 156,915 Municipal 136,831 2,427 (768 ) 138,490 113,197 2,712 (557 ) 115,352 Corporate notes: Financial issuers 97,079 35 (7,069 ) 90,045 30,309 43 (301 ) 30,051 Other 1,000 — — 1,000 1,000 — (1 ) 999 Mortgage-backed: (1) Mortgage-backed securities 1,641,146 2,510 (57,317 ) 1,586,339 1,291,695 446 (31,955 ) 1,260,186 Collateralized mortgage obligations 43,819 500 (823 ) 43,496 60,092 64 (617 ) 59,539 Equity securities (2) — — — — 34,234 3,357 (789 ) 36,802 Total available-for-sale securities $ 2,185,494 $ 6,780 $ (66,193 ) $ 2,126,081 $ 1,833,069 $ 6,624 $ (36,027 ) $ 1,803,666 Held-to-maturity securities U.S. Government agencies $ 814,864 $ 1,141 $ (28,576 ) $ 787,429 $ 579,062 $ 23 $ (14,066 ) $ 565,019 Municipal 252,575 1,100 (5,008 ) 248,667 247,387 2,668 (2,558 ) 247,497 Total held-to-maturity securities $ 1,067,439 $ 2,241 $ (33,584 ) $ 1,036,096 $ 826,449 $ 2,691 $ (16,624 ) $ 812,516 Equity securities with readily determinable fair value (2) $ 34,410 $ 1,532 $ (1,225 ) $ 34,717 $ — $ — $ — $ — (1) Consisting entirely of residential mortgage-backed securities, none of which are subprime. (2) As a result of the adoption of ASU No. 2016-01 effective January 1, 2018, equity securities with readily determinable fair value are no longer presented within available-for-sale securities and are now presented as equity securities with readily determinable fair values in the Company's Consolidated Statements of Condition for the current period. Equity securities without readily determinable fair values totaled $26.6 million as of December 31, 2018. Equity securities without readily determinable fair values are included as part of accrued interest receivable and other assets in the Company's Consolidated Statements of Condition. The Company recorded a $325,000 upward adjustments on such equity securities in 2018 related to observable price changes in orderly transactions for the identical or a similar investment of the same issuer in accordance with the adoption of ASU No. 2016-01. No downward adjustments of equity securities without readily determinable fair values related to observable price changes in orderly transactions for the identical or a similar investment of the same issuer were recorded during the same period. The Company monitors its equity investments without a readily determinable fair values to identify potential transactions that may indicate an observable price change requiring adjustment to its carrying amount. The following table presents the portion of the Company’s available-for-sale and held-to-maturity securities portfolios which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at December 31, 2018 : Continuous unrealized losses existing for less than 12 months Continuous unrealized losses existing for greater than 12 months Total (Dollars in thousands) Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Available-for-sale securities U.S. Treasury $ 5,485 $ (5 ) $ 24,829 $ (181 ) $ 30,314 $ (186 ) U.S. Government agencies — — 11,167 (30 ) 11,167 (30 ) Municipal 10,676 (178 ) 22,147 (590 ) 32,823 (768 ) Corporate notes: Financial issuers 37,076 (2,921 ) 42,934 (4,148 ) 80,010 (7,069 ) Other — — — — — — Mortgage-backed: Mortgage-backed securities 114,958 (124 ) 1,340,916 (57,193 ) 1,455,874 (57,317 ) Collateralized mortgage obligations 510 (1 ) 34,255 (822 ) 34,765 (823 ) Total available-for-sale securities $ 168,705 $ (3,229 ) $ 1,476,248 $ (62,964 ) $ 1,644,953 $ (66,193 ) Held-to-maturity securities U.S. Government agencies $ — $ — $ 601,238 $ (28,576 ) $ 601,238 $ (28,576 ) Municipal 38,239 (637 ) 158,302 (4,371 ) 196,541 (5,008 ) Total held-to-maturity securities $ 38,239 $ (637 ) $ 759,540 $ (32,947 ) $ 797,779 $ (33,584 ) The following table presents the portion of the Company’s available-for-sale and held-to-maturity securities portfolios which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at December 31, 2017 : Continuous unrealized losses existing for less than 12 months Continuous unrealized losses existing for greater than 12 months Total (Dollars in thousands) Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Available-for-sale securities U.S. Treasury $ 24,811 $ (215 ) $ 119,011 $ (867 ) $ 143,822 $ (1,082 ) U.S. Government agencies 14,462 (69 ) 141,471 (656 ) 155,933 (725 ) Municipal 28,221 (256 ) 15,840 (301 ) 44,061 (557 ) Corporate notes: Financial issuers 1,210 (1 ) 5,665 (300 ) 6,875 (301 ) Other — — 999 (1 ) 999 (1 ) Mortgage-backed: Mortgage-backed securities 137,255 (915 ) 989,971 (31,040 ) 1,127,226 (31,955 ) Collateralized mortgage obligations 35,038 (213 ) 13,719 (404 ) 48,757 (617 ) Equity securities 9,116 (343 ) 6,054 (446 ) 15,170 (789 ) Total available-for-sale securities $ 250,113 $ (2,012 ) $ 1,292,730 $ (34,015 ) $ 1,542,843 $ (36,027 ) Held-to-maturity securities U.S. Government agencies $ 241,849 $ (3,263 ) $ 300,200 $ (10,803 ) $ 542,049 $ (14,066 ) Municipal 56,901 (1,004 ) 52,399 (1,554 ) 109,300 (2,558 ) Total held-to-maturity securities $ 298,750 $ (4,267 ) $ 352,599 $ (12,357 ) $ 651,349 $ (16,624 ) The Company conducts a regular assessment of its investment securities to determine whether securities are other-than-temporarily impaired considering, among other factors, the nature of the securities, credit ratings or financial condition of the issuer, the extent and duration of the unrealized loss, expected cash flows, market conditions and the Company’s ability to hold the securities through the anticipated recovery period. The Company does not consider securities with unrealized losses at December 31, 2018 to be other-than-temporarily impaired. The Company does not intend to sell these investments and it is more likely than not that the Company will not be required to sell these investments before recovery of the amortized cost bases, which may be the maturity dates of the securities. The unrealized losses within each category have occurred as a result of changes in interest rates, market spreads and market conditions subsequent to purchase. Securities with continuous unrealized losses existing for more than twelve months were primarily U.S. Treasury securities, U.S. government agency securities, municipal securities, corporate notes and mortgage-backed securities. The following table provides information as to the amount of gross gains and gross losses realized and proceeds received through the sales and calls of investment securities: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Realized gains on investment securities $ 1,144 $ 147 $ 9,399 Realized losses on investment securities (1,111 ) (102 ) (1,754 ) Net realized gains on investment securities 33 $ 45 $ 7,645 Unrealized gains on equity securities with readily determinable fair value 2,771 — — Unrealized losses on equity securities with readily determinable fair value (4,910 ) — — Net unrealized losses on equity securities with readily determinable fair value (2,139 ) — — Upward adjustments of equity securities without readily determinable fair values 325 — — Downward adjustments of equity securities without readily determinable fair values — — — Impairment of equity securities without readily determinable fair values (1,117 ) — — Adjustment and impairment, net, of equity securities without readily determinable fair values (792 ) — — Other than temporary impairment charges — — — (Losses) gains on investment securities, net (2,898 ) 45 7,645 Proceeds from sales of available-for-sale securities 214,196 344,674 2,194,278 Proceeds from sales of equity securities with readily determinable fair value 1,895 — — Proceeds from sales and capital distributions of equity securities without readily determinable fair value 1,324 — — During the year ended December 31, 2018, the Company recorded $1.1 million of impairment of equity securities without readily determinable fair values. The Company conducts a quarterly assessment of its equity securities without readily determinable fair values to determine whether impairment exists in such equity securities, considering, among other factors, the nature of the securities, financial condition of the issuer and expected future cash flows. Net losses/gains on investment securities resulted in income tax (benefit) expense of ($737,000) , $18,000 and $2.9 million in 2018 , 2017 and 2016 , respectively. The amortized cost and fair value of securities as of December 31, 2018 and December 31, 2017 , by contractual maturity, are shown in the following table. Contractual maturities may differ from actual maturities as borrowers may have the right to call or repay obligations with or without call or prepayment penalties. Mortgage-backed securities are not included in the maturity categories in the following maturity summary as actual maturities may differ from contractual maturities because the underlying mortgages may be called or prepaid without penalties: December 31, 2018 December 31, 2017 (Dollars in thousands) Amortized Cost Fair Value Amortized Cost Fair Value Available-for-sale securities Due in one year or less $ 82,206 $ 82,153 $ 300,833 $ 299,285 Due in one to five years 168,855 169,307 97,019 97,326 Due in five to ten years 121,129 115,206 33,947 35,029 Due after ten years 128,339 129,580 15,249 15,499 Mortgage-backed 1,684,965 1,629,835 1,351,787 1,319,725 Equity securities (1) — — 34,234 36,802 Total available-for-sale securities $ 2,185,494 $ 2,126,081 $ 1,833,069 $ 1,803,666 Held-to-maturity securities Due in one year or less $ 10,009 $ 9,979 $ 170 $ 171 Due in one to five years 29,436 28,995 38,392 38,012 Due in five to ten years 295,897 290,206 205,227 203,680 Due after ten years 732,097 706,916 582,660 570,653 Total held-to-maturity securities $ 1,067,439 $ 1,036,096 $ 826,449 $ 812,516 (1) As a result of the adoption of ASU No. 2016-01 effective January 1, 2018, equity securities with readily determinable fair value are no longer presented within available-for-sale securities and are now presented as equity securities with readily determinable fair values in the Company's Consolidated Statements of Condition for the current period. At December 31, 2018 and December 31, 2017 , securities having a carrying value of $1.7 billion , were pledged as collateral for public deposits, trust deposits, FHLB advances, securities sold under repurchase agreements and derivatives. At December 31, 2018 , there were no securities of a single issuer, other than U.S. Government-sponsored agency securities, which exceeded 10% of shareholders’ equity.

Loans

Loans	12 Months Ended
	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Abstract]
Loans	Loans The following table shows the Company's loan portfolio by category as of the dates shown: (Dollars in thousands) December 31, 2018 December 31, 2017 Balance: Commercial $ 7,828,538 $ 6,787,677 Commercial real estate 6,933,252 6,580,618 Home equity 552,343 663,045 Residential real estate 1,002,464 832,120 Premium finance receivables—commercial 2,841,659 2,634,565 Premium finance receivables—life insurance 4,541,794 4,035,059 Consumer and other 120,641 107,713 Total loans, net of unearned income $ 23,820,691 $ 21,640,797 Mix: Commercial 33 % 31 % Commercial real estate 29 30 Home equity 2 3 Residential real estate 4 4 Premium finance receivables—commercial 12 12 Premium finance receivables—life insurance 19 19 Consumer and other 1 1 Total loans, net of unearned income 100 % 100 % The Company’s loan portfolio is generally comprised of loans to consumers and small to medium-sized businesses located within the geographic market areas that the banks serve. The premium finance receivables portfolios are made to customers throughout the United States and Canada. The Company strives to maintain a loan portfolio that is diverse in terms of loan type, industry, borrower and geographic concentrations. Such diversification reduces the exposure to economic downturns that may occur in different segments of the economy or in different industries. Certain premium finance receivables are recorded net of unearned income. The unearned income portions of such premium finance receivables were $112.9 million and $87.0 million at December 31, 2018 and 2017 , respectively. Total loans, excluding PCI loans, include net deferred loan fees and costs and fair value purchase accounting adjustments totaling $4.5 million and $9.3 million at December 31, 2018 and 2017 , respectively. PCI loans are recorded net of credit discounts. See "Acquired Loan Information at Acquisition - PCI Loans" below. Certain real estate loans, including mortgage loans held-for-sale, and home equity loans with balances totaling approximately $6.1 billion and $6.4 billion at December 31, 2018 and 2017, respectively, were pledged as collateral to secure the availability of borrowings from certain federal agency banks. At December 31, 2018, approximately $5.7 billion of these pledged loans are included in a blanket pledge of qualifying loans to the FHLB. The remaining $484.6 million of pledged loans was used to secure potential borrowings at the FRB discount window. At December 31, 2018 and 2017 , the banks had outstanding borrowings of $426.3 million and $559.7 million , respectively, from the FHLB in connection with these collateral arrangements. See Note 11, “Federal Home Loan Bank Advances,” for a summary of these borrowings. It is the policy of the Company to review each prospective credit in order to determine the appropriateness and, when required, the adequacy of security or collateral necessary to obtain when making a loan. The type of collateral, when required, will vary from liquid assets to real estate. The Company seeks to assure access to collateral, in the event of default, through adherence to state lending laws and the Company’s credit monitoring procedures. Acquired Loan Information at Acquisition — PCI Loans As part of the Company's previous acquisitions, the Company acquired loans for which there was evidence of credit quality deterioration since origination (PCI loans) and we determined that it was probable that the Company would be unable to collect all contractually required principal and interest payments. The following table presents the unpaid principal balance and carrying value for these acquired loans as of the dates shown: December 31, 2018 December 31, 2017 (Dollars in thousands) Unpaid Principal Balance Carrying Value Unpaid Principal Balance Carrying Value PCI loans $ 341,555 $ 318,394 $ 375,237 $ 350,690 See Note 5, “Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans,” for further discussion regarding the allowance for loan losses associated with PCI loans at December 31, 2018. The following table provides estimated details as of the date of acquisition on loans acquired in 2018 with evidence of credit quality deterioration since origination: (Dollars in thousands) Delaware Place Bank American Enterprise Bank Contractually required payments including interest $ 13,385 $ 31,750 Less: Nonaccretable difference 1,197 3,813 Cash flows expected to be collected (1) $ 12,188 $ 27,937 Less: Accretable yield 2,205 3,970 Fair value of PCI loans acquired $ 9,983 $ 23,967 (1) Represents undiscounted expected principal and interest cash at acquisition. Accretable Yield Activity — PCI Loans Changes in expected cash flows may vary from period to period as the Company periodically updates its cash flow model assumptions for PCI loans. The factors that most significantly affect the estimates of gross cash flows expected to be collected, and accordingly the accretable yield, include changes in the benchmark interest rate indices for variable-rate products and changes in prepayment assumptions and loss estimates. The following table provides activity for the accretable yield of PCI loans. Years Ended December 31, (Dollars in thousands) 2018 2017 Accretable yield, beginning balance $ 36,565 $ 49,408 Acquisitions 6,175 426 Accretable yield amortized to interest income (16,711 ) (21,512 ) Accretable yield amortized to indemnification asset/liability (1) — (1,087 ) Reclassification from non-accretable difference (2) 4,835 7,805 Increases (Decreases) in interest cash flows due to payments and changes in interest rates 4,012 1,525 Accretable yield, ending balance $ 34,876 $ 36,565 (1) Represents the portion of the current period accreted yield, resulting from lower expected losses, applied to reduce the loss share indemnification asset or increase the loss share indemnification liability. (2) Reclassification is the result of subsequent increases in expected principal cash flows. Accretion to interest income accounted for under ASC 310-30 totaled $16.7 million and $21.5 million in 2018 and 2017, respectively. These amounts include accretion from both covered and non-covered loans, and are included together within interest and fees on loans in the Consolidated Statements of Income.

Allowance for Loan Losses, Allo

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans	12 Months Ended
	Dec. 31, 2018
Receivables [Abstract]
Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans	Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans The tables below show the aging of the Company’s loan portfolio at December 31, 2018 and 2017 : As of December 31, 2018 (Dollars in thousands) Nonaccrual 90+ days and still accruing 60-89 days past due 30-59 days past due Current Total Loans Loan Balances: Commercial Commercial, industrial and other $ 34,298 $ — $ 1,451 $ 21,618 $ 5,062,729 $ 5,120,096 Franchise 16,051 — — 8,738 924,190 948,979 Mortgage warehouse lines of credit — — — — 144,199 144,199 Asset-based lending 635 — 200 3,156 1,022,065 1,026,056 Leases — — — 1,250 564,430 565,680 PCI - commercial (1) — 3,313 — 99 20,116 23,528 Total commercial $ 50,984 $ 3,313 $ 1,651 $ 34,861 $ 7,737,729 $ 7,828,538 Commercial real estate: Construction 1,554 — — 9,424 749,846 760,824 Land 107 — 170 107 141,097 141,481 Office 3,629 — 877 5,077 929,739 939,322 Industrial 285 — — 16,596 885,367 902,248 Retail 10,753 — 1,890 1,729 878,106 892,478 Multi-family 311 — 77 5,575 970,597 976,560 Mixed use and other 2,490 — 1,617 8,983 2,192,105 2,205,195 PCI - commercial real estate (1) — 6,241 6,195 4,075 98,633 115,144 Total commercial real estate $ 19,129 $ 6,241 $ 10,826 $ 51,566 $ 6,845,490 $ 6,933,252 Home equity 7,147 — 131 3,105 541,960 552,343 Residential real estate, including PCI 16,383 1,292 1,692 6,171 976,926 1,002,464 Premium finance receivables Commercial insurance loans 11,335 7,799 11,382 15,085 2,796,058 2,841,659 Life insurance loans — — 8,407 24,628 4,340,856 4,373,891 PCI - life insurance loans (1) — — — — 167,903 167,903 Consumer and other, including PCI 348 227 87 733 119,246 120,641 Total loans, net of unearned income $ 105,326 $ 18,872 $ 34,176 $ 136,149 $ 23,526,168 $ 23,820,691 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. Loan agings are based upon contractually required payments. See Note 4 , “Loans,” for further discussion of these purchased loans. As of December 31, 2017 (Dollars in thousands) Nonaccrual 90+ days and still accruing 60-89 days past due 30-59 days past due Current Total Loans Loan Balances: Commercial Commercial, industrial and other $ 11,260 $ — $ 3,746 $ 13,392 $ 4,314,107 $ 4,342,505 Franchise 2,447 — — — 845,150 847,597 Mortgage warehouse lines of credit — — — 4,000 190,523 194,523 Asset-based lending 1,550 — 283 10,057 968,576 980,466 Leases 439 — 3 1,958 410,772 413,172 PCI - commercial (1) — 877 186 — 8,351 9,414 Total commercial $ 15,696 $ 877 $ 4,218 $ 29,407 $ 6,737,479 $ 6,787,677 Commercial real estate Construction $ 3,143 $ — $ — $ 200 $ 742,171 $ 745,514 Land 188 — — 5,156 121,140 126,484 Office 2,438 — — 4,458 887,937 894,833 Industrial 811 — — 2,412 879,796 883,019 Retail 12,328 — 668 148 938,383 951,527 Multi-family — — — 1,034 914,610 915,644 Mixed use and other 3,140 — 1,423 9,641 1,921,501 1,935,705 PCI - commercial real estate (1) — 7,135 2,255 6,277 112,225 127,892 Total commercial real estate $ 22,048 $ 7,135 $ 4,346 $ 29,326 $ 6,517,763 $ 6,580,618 Home equity 8,978 — 518 4,634 648,915 663,045 Residential real estate, including PCI 17,977 5,304 1,303 8,378 799,158 832,120 Premium finance receivables Commercial insurance loans 12,163 9,242 17,796 15,849 2,579,515 2,634,565 Life insurance loans — — 4,837 10,017 3,820,936 3,835,790 PCI - life insurance loans (1) — — — — 199,269 199,269 Consumer and other, including PCI 740 101 242 727 105,903 107,713 Total loans, net of unearned income, excluding covered loans 77,602 22,659 33,260 98,338 21,408,938 21,640,797 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. Loan agings are based upon contractually required payments. See Note 4 , “Loans,” for further discussion of these purchased loans. The Company's ability to manage credit risk depends in large part on our ability to properly identify and manage problem loans. To do so, the Company operates a credit risk rating system under which credit management personnel assign a credit risk rating (1 to 10 rating) to each loan at the time of origination and review loans on a regular basis. Each loan officer is responsible for monitoring his or her loan portfolio, recommending a credit risk rating for each loan in his or her portfolio and ensuring the credit risk ratings are appropriate. These credit risk ratings are then ratified by the bank’s chief credit officer and/or concurrence credit officer. Credit risk ratings are determined by evaluating a number of factors including: a borrower’s financial strength, cash flow coverage, collateral protection and guarantees. The Company’s Problem Loan Reporting system includes all loans with credit risk ratings of 6 through 9. This system is designed to provide an on-going detailed tracking mechanism for each problem loan. Once management determines that a loan has deteriorated to a point where it has a credit risk rating of 6 or worse, the Company’s Managed Asset Division performs an overall credit and collateral review. As part of this review, all underlying collateral is identified and the valuation methodology is analyzed and tracked. As a result of this initial review by the Company’s Managed Asset Division, the credit risk rating is reviewed and a portion of the outstanding loan balance may be deemed uncollectible or an impairment reserve may be established. The Company’s impairment analysis utilizes an independent re-appraisal of the collateral (unless such a third-party evaluation is not possible due to the unique nature of the collateral, such as a closely-held business or thinly traded securities). In the case of commercial real estate collateral, an independent third party appraisal is ordered by the Company’s Real Estate Services Group to determine if there has been any change in the underlying collateral value. These independent appraisals are reviewed by the Real Estate Services Group and sometimes by independent third party valuation experts and may be adjusted depending upon market conditions. Through the credit risk rating process, loans are reviewed to determine if they are performing in accordance with the original contractual terms. If the borrower has failed to comply with the original contractual terms, further action may be required by the Company, including a downgrade in the credit risk rating, movement to non-accrual status, a charge-off or the establishment of a specific impairment reserve. If the Company determines that a loan amount or portion thereof is uncollectible the loan’s credit risk rating is immediately downgraded to an 8 or 9 and the uncollectible amount is charged-off. Any loan that has a partial charge-off continues to be assigned a credit risk rating of an 8 or 9 for the duration of time that a balance remains outstanding. The Company undertakes a thorough and ongoing analysis to determine if additional impairment and/or charge-offs are appropriate and to begin a workout plan for the credit to minimize actual losses. If, based on current information and events, it is probable that the Company will be unable to collect all amounts due to it according to the contractual terms of the loan agreement, a specific impairment reserve is established. In determining the appropriate charge-off for collateral-dependent loans, the Company considers the results of appraisals for the associated collateral. Non-performing loans include all non-accrual loans (8 and 9 risk ratings) as well as loans 90 days past due and still accruing interest, excluding PCI loans. The remainder of the portfolio is considered performing under the contractual terms of the loan agreement. The following table presents the recorded investment based on performance of loans by class, per the most recent analysis at December 31, 2018 and 2017 : Performing Non-performing Total December 31, December 31, December 31, December 31, December 31, December 31, (Dollars in thousands) 2018 2017 2018 2017 2018 2017 Loan Balances: Commercial Commercial, industrial and other $ 5,085,798 $ 4,331,245 $ 34,298 $ 11,260 $ 5,120,096 $ 4,342,505 Franchise 932,928 845,150 16,051 2,447 948,979 847,597 Mortgage warehouse lines of credit 144,199 194,523 — — 144,199 194,523 Asset-based lending 1,025,421 978,916 635 1,550 1,026,056 980,466 Leases 565,680 412,733 — 439 565,680 413,172 PCI - commercial (1) 23,528 9,414 — — 23,528 9,414 Total commercial $ 7,777,554 $ 6,771,981 $ 50,984 $ 15,696 $ 7,828,538 $ 6,787,677 Commercial real estate Construction 759,270 742,371 1,554 3,143 760,824 745,514 Land 141,374 126,296 107 188 141,481 126,484 Office 935,693 892,395 3,629 2,438 939,322 894,833 Industrial 901,963 882,208 285 811 902,248 883,019 Retail 881,725 939,199 10,753 12,328 892,478 951,527 Multi-family 976,249 915,644 311 — 976,560 915,644 Mixed use and other 2,202,705 1,932,565 2,490 3,140 2,205,195 1,935,705 PCI - commercial real estate (1) 115,144 127,892 — — 115,144 127,892 Total commercial real estate $ 6,914,123 $ 6,558,570 $ 19,129 $ 22,048 $ 6,933,252 $ 6,580,618 Home equity 545,196 654,067 7,147 8,978 552,343 663,045 Residential real estate, including PCI 986,081 810,865 16,383 21,255 1,002,464 832,120 Premium finance receivables Commercial insurance loans 2,822,525 2,613,160 19,134 21,405 2,841,659 2,634,565 Life insurance loans 4,373,891 3,835,790 — — 4,373,891 3,835,790 PCI - life insurance loans (1) 167,903 199,269 — — 167,903 199,269 Consumer and other, including PCI 120,184 106,933 457 780 120,641 107,713 Total loans, net of unearned income, excluding covered loans $ 23,707,457 $ 21,550,635 $ 113,234 $ 90,162 $ 23,820,691 $ 21,640,797 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 4 , “Loans,” for further discussion of these purchased loans. A summary of the activity in the allowance for credit losses by loan portfolio (excluding covered loans) for the years ended December 31, 2018 and 2017 is as follows: Year Ended December 31, 2018 (Dollars in thousands) Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans Allowance for credit losses Allowance for loan losses at beginning of period $ 57,811 $ 55,227 $ 10,493 $ 6,688 $ 6,846 $ 840 $ 137,905 Other adjustments (3 ) (85 ) (5 ) (25 ) (63 ) — (181 ) Reclassification to/from allowance for unfunded lending-related commitments — (126 ) — — — — (126 ) Charge-offs (14,532 ) (1,395 ) (2,245 ) (1,355 ) (12,228 ) (880 ) (32,635 ) Recoveries 1,457 5,631 541 2,075 3,069 202 12,975 Provision for credit losses 23,093 1,015 (277 ) (189 ) 10,091 1,099 34,832 Allowance for loan losses at period end $ 67,826 $ 60,267 $ 8,507 $ 7,194 $ 7,715 $ 1,261 $ 152,770 Allowance for unfunded lending-related commitments at period end — 1,394 — — — — 1,394 Allowance for credit losses at period end $ 67,826 $ 61,661 $ 8,507 $ 7,194 $ 7,715 $ 1,261 $ 154,164 By measurement method: Individually evaluated for impairment 6,558 4,287 282 204 — 116 11,447 Collectively evaluated for impairment 60,749 57,329 8,225 6,894 7,715 1,145 142,057 Loans acquired with deteriorated credit quality 519 45 — 96 — — 660 Loans at period end: Individually evaluated for impairment $ 59,529 $ 33,274 $ 12,255 $ 22,064 $ — $ 397 $ 127,519 Collectively evaluated for impairment 7,745,482 6,784,834 540,088 877,526 7,215,550 117,441 23,280,921 Loans acquired with deteriorated credit quality 23,527 115,144 — 9,017 167,903 2,803 318,394 Loan held at fair value — — — 93,857 — — 93,857 Year Ended December 31, 2017 (Dollars in thousands) Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans Allowance for credit losses Allowance for loan losses at beginning of period $ 44,493 $ 51,422 $ 11,774 $ 5,714 $ 7,625 $ 1,263 $ 122,291 Other adjustments (1) 16 (155 ) 167 356 138 51 573 Reclassification to/from allowance for unfunded lending-related commitments 500 (431 ) — — — — 69 Charge-offs (5,159 ) (4,236 ) (3,952 ) (1,284 ) (7,335 ) (729 ) (22,695 ) Recoveries 1,870 2,190 746 452 2,128 299 7,685 Provision for credit losses 16,091 6,437 1,758 1,450 4,290 (44 ) 29,982 Allowance for loan losses at period end $ 57,811 $ 55,227 $ 10,493 $ 6,688 $ 6,846 $ 840 $ 137,905 Allowance for unfunded lending-related commitments at period end — 1,269 — — — — 1,269 Allowance for credit losses at period end $ 57,811 $ 56,496 $ 10,493 $ 6,688 $ 6,846 $ 840 $ 139,174 By measurement method: Individually evaluated for impairment 4,464 2,177 784 586 — 26 8,037 Collectively evaluated for impairment 52,820 53,938 9,709 5,979 6,846 814 130,106 Loans acquired with deteriorated credit quality 527 381 — 123 — — 1,031 Loans at period end: Individually evaluated for impairment $ 35,612 $ 38,534 $ 9,254 $ 21,253 $ — $ 759 $ 105,412 Collectively evaluated for impairment 6,742,651 6,414,192 653,791 765,149 6,470,355 104,840 21,150,978 Loans acquired with deteriorated credit quality 9,414 127,892 — 12,001 199,269 2,114 350,690 Loan held at fair value — — — 33,717 — — 33,717 (1) Includes $742,000 of allowance for covered loan losses reclassified as a result of the termination of all existing loss share agreements with the FDIC during the fourth quarter of 2017. A summary of activity in the allowance for covered loan losses for the year ended December 31, 2017 is as follows: Year Ended December 31, (Dollars in thousands) 2017 Balance at beginning of period $ 1,322 Allowance for covered loan losses transferred to allowance for loan losses subsequent to loss share termination or expiration (742 ) Provision for covered loan losses before benefit attributable to FDIC loss share agreements (1,063 ) Benefit attributable to FDIC loss share agreements 1,592 Net provision for covered loan losses and transfer from allowance for covered loan losses to allowance for loan losses $ (213 ) Increase in FDIC indemnification liability (1,592 ) Loans charged-off (517 ) Recoveries of loans charged-off 1,000 Net recoveries $ 483 Balance at end of period $ — In conjunction with FDIC-assisted transactions, the Company entered into loss share agreements with the FDIC. Additional expected losses, to the extent such expected losses resulted in the recognition of an allowance for loan losses, increased the FDIC loss share asset or reduced any FDIC loss share liability. The allowance for loan losses for loans acquired in FDIC-assisted transactions was determined without giving consideration to the amounts recoverable through loss share agreements (since the loss share agreements are separately accounted for and thus presented “gross” on the balance sheet). On the Consolidated Statements of Income, the provision for credit losses was reported net of changes in the amount recoverable under the loss share agreements. Reductions to expected losses, to the extent such reductions to expected losses were the result of an improvement to the actual or expected cash flows from the covered assets, reduced the FDIC loss share asset or increased any FDIC loss share liability. Additions to expected losses required an increase to the allowance for loan losses, and a corresponding increase to the FDIC loss share asset or reduction to any FDIC loss share liability. See “FDIC-Assisted Bank Acquisitions” within Note 7, “Business Combinations and Asset Acquisitions,” for more detail. On October 16, 2017, the Company entered into agreements with the FDIC that terminated all existing loss share agreements with the FDIC. As a result, the allowance for covered loan losses previously measured is included within the allowance for credit losses, excluding covered loans, presented above for subsequent periods. See Note 7, "Business Combinations and Asset Acquisitions," for further discussion of the termination of FDIC loss share agreements. Impaired Loans A summary of impaired loans, including TDRs, at December 31, 2018 and 2017 is as follows: (Dollars in thousands) 2018 2017 Impaired loans (included in non-performing and restructured loans): Impaired loans with an allowance for loan loss required (1) $ 60,219 $ 36,084 Impaired loans with no allowance for loan loss required 67,050 69,004 Total impaired loans (2) $ 127,269 $ 105,088 Allowance for loan losses related to impaired loans $ 11,437 $ 8,023 TDRs 66,102 49,786 Reduction of interest income from non-accrual loans 3,422 2,373 Interest income recognized on impaired loans 7,347 6,298 (1) These impaired loans require an allowance for loan losses because the estimated fair value of the loans or related collateral is less than the recorded investment in the loans. (2) Impaired loans are considered by the Company to be non-accrual loans, TDRs or loans with principal and/or interest at risk, even if the loan is current with all payments of principal and interest. The following tables present impaired loans evaluated for impairment by loan class as of December 31, 2018 and 2017 : As of For the Year Ended December 31, 2018 (Dollars in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized Impaired loans with a related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 16,703 $ 17,029 $ 4,866 $ 17,868 $ 1,181 Franchise 16,021 16,256 1,375 16,221 909 Asset-based lending 557 557 317 689 50 Leases 1,730 1,730 — 1,812 91 Commercial real estate Construction 1,554 1,554 550 1,554 76 Land — — — — — Office 573 638 21 587 25 Industrial — — — — — Retail 14,633 14,633 3,413 14,694 676 Multi-family — — — — — Mixed use and other 1,188 1,221 293 1,354 66 Home equity 3,133 3,470 282 3,165 131 Residential real estate 4,011 4,263 204 4,056 159 Consumer and other 116 129 116 119 7 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 18,314 $ 21,501 $ — $ 20,547 $ 1,143 Franchise 5,152 5,154 — 5,320 403 Asset-based lending 207 601 — 569 51 Leases 845 879 — 936 56 Commercial real estate Construction 1,117 1,117 — 1,218 52 Land 3,396 3,491 — 3,751 198 Office 3,629 3,642 — 3,651 184 Industrial 322 450 — 363 30 Retail 1,592 1,945 — 1,699 110 Multi-family 1,498 1,595 — 1,529 55 Mixed use and other 3,522 3,836 — 3,611 227 Home equity 9,122 12,383 — 9,323 564 Residential real estate 18,053 20,765 — 18,552 883 Consumer and other 281 407 — 293 20 Total loans, net of unearned income $ 127,269 $ 139,246 $ 11,437 $ 133,481 $ 7,347 As of For the Year Ended December 31, 2017 (Dollars in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized Impaired loans with a related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 6,233 $ 7,323 $ 3,951 $ 7,220 $ 452 Franchise — — — — — Asset-based lending 948 949 355 1,302 72 Leases 2,331 2,337 158 2,463 117 Commercial real estate Construction 3,097 3,897 403 3,690 197 Land — — — — Office 471 471 5 481 24 Industrial 408 408 40 414 25 Retail 15,599 15,657 1,336 15,736 624 Multi-family — — — — — Mixed use and other 1,567 1,586 379 1,599 77 Home equity 1,606 1,869 784 1,626 81 Residential real estate 3,798 3,910 586 3,790 146 Consumer and other 26 28 26 27 2 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 8,460 $ 12,259 $ — $ 10,170 $ 683 Franchise 16,256 16,256 — 17,089 780 Asset-based lending 602 602 — 688 40 Leases 782 782 — 845 49 Commercial real estate Construction 1,367 1,678 — 1,555 84 Land 3,961 4,192 — 4,129 182 Office 2,438 6,140 — 3,484 330 Industrial 403 2,010 — 1,849 174 Retail 2,393 3,538 — 2,486 221 Multi-family 1,231 2,078 — 1,246 76 Mixed use and other 5,275 6,731 — 5,559 351 Home equity 7,648 11,648 — 9,114 603 Residential real estate 17,455 20,327 — 17,926 860 Consumer and other 733 890 — 773 48 Total loans, net of unearned income $ 105,088 $ 127,566 $ 8,023 $ 115,261 $ 6,298 Average recorded investment in impaired loans for the years ended December 31, 2018 , 2017 , and 2016 were $133.5 million , $115.3 million , and $105.4 million , respectively. Interest income recognized on impaired loans was $7.3 million , $6.3 million and $5.5 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. TDRs At December 31, 2018 , the Company had $66.1 million in loans modified in TDRs. The $66.1 million in TDRs represents 134 credits in which economic concessions were granted to certain borrowers to better align the terms of their loans with their current ability to pay. The Company’s approach to restructuring loans, excluding PCI loans, is built on its credit risk rating system which requires credit management personnel to assign a credit risk rating to each loan. In each case, the loan officer is responsible for recommending a credit risk rating for each loan and ensuring the credit risk ratings are appropriate. These credit risk ratings are then reviewed and approved by the bank’s chief credit officer and/or concurrence credit officer. Credit risk ratings are determined by evaluating a number of factors including a borrower’s financial strength, cash flow coverage, collateral protection and guarantees. The Company’s credit risk rating scale is one through ten with higher scores indicating higher risk. In the case of loans rated six or worse following modification, the Company’s Managed Assets Division evaluates the loan and the credit risk rating and determines that the loan has been restructured to be reasonably assured of repayment and of performance according to the modified terms and is supported by a current, well-documented credit assessment of the borrower’s financial condition and prospects for repayment under the revised terms. A modification of a loan, excluding PCI loans, with an existing credit risk rating of 6 or worse or a modification of any other credit, which will result in a restructured credit risk rating of 6 or worse, must be reviewed for possible TDR classification. In that event, our Managed Assets Division conducts an overall credit and collateral review. A modification of these loans is considered to be a TDR if both (1) the borrower is experiencing financial difficulty and (2) for economic or legal reasons, the bank grants a concession to a borrower that it would not otherwise consider. The modification of a loan, excluding PCI loans, where the credit risk rating is 5 or better both before and after such modification is not considered to be a TDR. Based on the Company’s credit risk rating system, it considers that borrowers whose credit risk rating is 5 or better are not experiencing financial difficulties and therefore, are not considered TDRs. All credits determined to be a TDR will continue to be classified as a TDR in all subsequent periods, unless the borrower has been in compliance with the loan’s modified terms for a period of six months (including over a calendar year-end) and the current interest rate represents a market rate at the time of restructuring. The Managed Assets Division, in consultation with the respective loan officer, determines whether the modified interest rate represented a current market rate at the time of restructuring. Using knowledge of current market conditions and rates, competitive pricing on recent loan originations, and an assessment of various characteristics of the modified loan (including collateral position and payment history), an appropriate market rate for a new borrower with similar risk is determined. If the modified interest rate meets or exceeds this market rate for a new borrower with similar risk, the modified interest rate represents a market rate at the time of restructuring. Additionally, before removing a loan from TDR classification, a review of the current or previously measured impairment on the loan and any concerns related to future performance by the borrower is conducted. If concerns exist about the future ability of the borrower to meet its obligations under the loans based on a credit review by the Managed Assets Division, the TDR classification is not removed from the loan. TDRs are reviewed at the time of modification and on a quarterly basis to determine if a specific reserve is necessary. The carrying amount of the loan is compared to the expected payments to be received, discounted at the loan’s original rate, or for collateral dependent loans, to the fair value of the collateral. Any shortfall is recorded as a specific reserve. The Company, in accordance with ASC 310-10, continues to individually measure impairment of these loans after the TDR classification is removed. Each TDR was reviewed for impairment at December 31, 2018 and approximately $2.1 million of impairment was present and appropriately reserved for through the Company’s normal reserving methodology in the Company’s allowance for loan losses. For TDRs in which impairment is calculated by the present value of future cash flows, the Company records interest income representing the decrease in impairment resulting from the passage of time during the respective period, which differs from interest income from contractually required interest on these specific loans. For the years ended December 31, 2018 and 2017 , the Company recorded $113,000 and $207,000 , respectively, in interest income representing this decrease in impairment. TDRs may arise in which, due to financial difficulties experienced by the borrower, the Company obtains through physical possession one or more collateral assets in satisfaction of all or part of an existing credit. Once possession is obtained, the Company reclassifies the appropriate portion of the remaining balance of the credit from loans to OREO, which is included within other assets in the Consolidated Statements of Condition. For any residential real estate property collateralizing a consumer mortgage loan, the Company is considered to possess the related collateral only if legal title is obtained upon completion of foreclosure, or the borrower conveys all interest in the residential real estate property to the Company through completion of a deed in lieu of foreclosure or similar legal agreement. At December 31, 2018 , the Company had $4.9 million of foreclosed residential real estate properties included within OREO. Further, the recorded investment in residential mortgage loans secured by residential real estate properties for which foreclosure proceedings are in process totaled $14.4 million and $9.8 million at December 31, 2018 and 2017, respectively. The tables below present a summary of the post-modification balance of loans restructured during the years ended December 31, 2018 , 2017 , and 2016 , which represent TDRs: Year ended December 31, 2018 Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 4 $ 13,441 3 $ 691 — $ — 1 $ 12,750 — $ — Franchise 3 5,157 1 35 — — 2 5,122 — — Asset-based lending 1 130 1 130 — — — — — — Leases 1 239 1 239 — — — — — — Commercial real estate Office 1 59 1 59 — — — — — — Industrial — — — — — — — — — — Mixed use and other 2 455 2 455 1 85 — — — — Residential real estate and other 59 9,762 58 9,523 27 2,789 — — 1 239 Total loans 71 $ 29,243 67 $ 11,132 28 $ 2,874 3 $ 17,872 1 $ 239 Year ended December 31, 2017 Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 5 $ 3,775 1 $ 95 1 $ 2,272 3 $ 1,408 — $ — Franchise 3 16,256 — — — — 3 16,256 — — Asset-based lending — — — — — — — — — — Leases — — — — — — — — — — Commercial real estate Office — — — — — — — — — — Industrial — — — — — — — — — — Mixed use and other 1 1,245 1 1,245 — — — — — — Residential real estate and other 12 3,049 10 2,925 8 2,643 1 55 1 69 Total loans 21 $ 24,325 12 $ 4,265 9 $ 4,915 7 $ 17,719 1 $ 69 Year ended December 31, 2016 Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 3 $ 345 3 $ 345 — $ — — $ — 1 $ 275 Franchise — — — — — — — — — — Asset-based lending — — — — — — — — — — Leases 2 2,949 2 2,949 — — — — — — Commercial real estate Office 1 450 1 450 — — — — — — Industrial 6 7,921 6 7,921 3 7,196 — — — — Mixed use and other 2 150 2 150 — — — — — — Residential real estate and other 7 1,082 5 841 6 850 2 470 — — Total loans 21 $ 12,897 19 $ 12,656 9 $ 8,046 2 $ 470 1 $ 275 (1) TDRs may have more than one modification representing a concession. As such, TDRs during the period may be represented in more than one of the categories noted above. (2) Balances represent the recorded investment in the loan at the time of the restructuring. During the year ended December 31, 2018 , $29.2 million , or 71 loans, were determined to be TDRs, compared to $24.3 million , or 21 loans, and $12.9 million , or 21 loans, in the years ended 2017 and 2016 , respectively. Of these loans extended at below market terms, the weighted average extension had a term of approximately 48 months in 2018 compared to 35 months in 2017 and 19 months in 2016 . Further, the weighted average decrease in the stated interest rate for loans with a reduction of interest rate during the period was approximately 172 basis points, 485 basis points and 34 basis points during the years ended December 31, 2018 , 2017 , and 2016 , respectively. Interest-only payment terms were approximately 7 months during the year ended 2018 compared to 11 months and 7 months for the years ended 2017 and 2016 , respectively. Additionally, $8,000 of principal balance were forgiven on the loans noted above in 2018 compared to $73,000 of principal balance forgiven during 2017 and $300,000 of principal balance forgiven during 2016 . The tables below present a summary of all loans restructured in TDRs during the years ended December 31, 2018 , 2017 , and 2016 , and such loans which were in payment default under the restructured terms during the respective periods: Year Ended December 31, 2018 Year Ended December 31, 2017 Year Ended December 31, 2016 Total (1)(3) Payments in Default (2)(3) Total (1)(3) Payments in Default (2)(3) Total (1)(3) Payments in Default (2)(3) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 4 $ 13,441 2 $ 174 5 $ 3,775 4 $ 3,681 3 $ 345 1 $ 28 Franchise 3 5,157 2 5,122 3 16,256 — — — — — — Asset-based lending 1 130 — — — — — — — — — — Leases 1 239 — — — — — — 2 2,949 — — Commercial real-estate Office 1 59 — — — — — — 1 450 1 450 Industrial — — — — — — — — 6 7,921 5 7,347 Mixed use and other 2 455 2 455 1 1,245 1 1,245 2 150 1 16 Residential real estate and other 59 9,762 9 1,957 12 3,049 3 2,052 7 1,082 — — Total loans 71 $ 29,243 15 $ 7,708 21 $ 24,325 8 $ 6,978 21 $ 12,897 8 $ 7,841 (1) Total TDRs represent all loans restructured in TDRs during the year indicated. (2) TDRs considered to be in payment default are over 30 days past-due subsequent to the restructuring. (3) Balances represent the recorded investment in the loan at the time of the restructuring.

Mortgage Servicing Rights

Mortgage Servicing Rights	12 Months Ended
	Dec. 31, 2018
Disclosures Pertaining to Servicing Assets and Servicing Liabilities [Abstract]
Mortgage Servicing Rights	Mortgage Servicing Rights ( “ MSRs”) Following is a summary of the changes in the carrying value of MSRs, accounted for at fair value, for the years ended December 31, 2018 , 2017 and 2016 : December 31, December 31, December 31, (Dollars in thousands) 2018 2017 2016 Balance at beginning of year $ 33,676 $ 19,103 $ 9,092 Additions from loans sold with servicing retained 33,071 18,341 13,091 Additions from acquisitions 13,806 — — Estimate of changes in fair value due to: Payoffs and paydowns (5,039 ) (2,595 ) (2,325 ) Changes in valuation inputs or assumptions (331 ) (1,173 ) (755 ) Fair value at end of year $ 75,183 $ 33,676 $ 19,103 Unpaid principal balance of mortgage loans serviced for others $ 6,545,870 $ 2,929,133 $ 1,784,760 The Company recognizes MSR assets upon the sale of residential real estate loans to external third parties when it retains the obligation to service the loans and the servicing fee is more than adequate compensation. The initial recognition of MSR assets from loans sold with servicing retained and subsequent changes in fair value of all MSRs are recognized in mortgage banking revenue. MSRs are subject to changes in value from actual and expected prepayment of the underlying loans. The Company does not specifically hedge the value of its MSRs. Fair values are determined by using a discounted cash flow model that incorporates the objective characteristics of the portfolio as well as subjective valuation parameters that purchasers of servicing would apply to such portfolios sold into the secondary market. The subjective factors include loan prepayment speeds, discount rates, servicing costs and other economic factors. The Company uses a third party to assist in the valuation of MSRs.

Business Combinations and Asset

Business Combinations and Asset Acquisitions	12 Months Ended
	Dec. 31, 2018
Business Combinations And Asset Acquisitions [Abstract]
Business Combinations and Asset Acquisitions	Business Combinations and Asset Acquisitions Non-FDIC Assisted Bank Acquisitions On December 7, 2018, the Company completed its acquisition of certain assets and the assumption of certain liabilities of AEB. Through this asset acquisition, the Company acquired approximately $164.0 million in assets, including approximately $119.3 million in loans, and approximately $150.8 million in deposits. On August 1, 2018, the Company completed its acquisition of CSC. CSC was the parent company of Delaware Place Bank. Through this business combination, the Company acquired Delaware Place Bank's one banking location in Chicago, Illinois, approximately $282.8 million in assets, including approximately $152.7 million in loans, and approximately $213.1 million in deposits. Additionally, the Company recorded goodwill of $26.5 million on the acquisition. On November 18, 2016 , the Company acquired FCFC. FCFC was the parent company of First Community Bank, Through this transaction, the Company acquired First Community Bank's two banking locations in Elgin, Illinois . First Community Bank was merged into the Company's wholly-owned subsidiary St. Charles Bank. The Company acquired assets with a fair value of approximately $187.3 million , including approximately $79.5 million of loans, and assumed deposits with a fair value of approximately $150.3 million . Additionally, the Company recorded goodwill of $13.8 million on the acquisition. On August 19, 2016 , the Company, through its wholly-owned subsidiary Lake Forest Bank, acquired approxim ately $561.4 million in performing loans and related relationships from an affiliate of GE Capital Franchise Finance, which were added to the Company's existing franchise finance portfolio. The loans are to franchise operators (primarily quick service restaurant concepts) in the Midwest and in the Western portion of the United States. On March 31, 2016 , the Company acquired Generations. Generations was the parent company of Foundations Bank, which had one banking location in Pewaukee, Wisconsin. Foundations Bank was merged into the Company's wholly-owned subsidiary Town Bank. The Company acquired assets with a fair value of approximately $134.2 million , including approximately $67.4 million of loans, and assumed deposits with a fair value of approximately $100.2 million . Additionally, the Company recorded goodwill of $11.5 million on the acquisition. FDIC Assisted Bank Acquisitions From 2010 to 2012, the Company acquired the banking operations, including the acquisition of certain assets and the assumption of liabilities, of nine financial institutions in FDIC-assisted transactions. Loans comprised the majority of the assets acquired in nearly all of these FDIC-assisted transactions, of which eight such transactions were subject to loss sharing agreements with the FDIC whereby the FDIC agreed to reimburse the Company for 80% of losses incurred on the purchased loans, other real estate owned (“OREO”), and certain other assets. Additionally, clawback provisions within these loss share agreements with the FDIC required the Company to reimburse the FDIC in the event that actual losses on covered assets were lower than the original loss estimates agreed upon with the FDIC with respect of such assets in the loss share agreements. The Company refers to the loans subject to these loss sharing agreements as “covered loans” and uses the term “covered assets” to refer to covered loans, covered OREO and certain other covered assets during periods subject to such agreements. As of dates subject to such agreements, the loans covered by the loss share agreements were classified and presented as covered loans and the estimated reimbursable losses were recorded as an FDIC indemnification asset or liability in the Consolidated Statements of Condition. The Company recorded the acquired assets and liabilities at their estimated fair values at the acquisition date. The fair value for loans reflected expected credit losses at the acquisition date. Therefore, the Company only recognized a provision for credit losses and charge-offs on the acquired loans for any further credit deterioration subsequent to the acquisition date. See Note 5, “Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans,” for further discussion of the allowance on covered loans. The loss share agreements with the FDIC covered realized losses on loans, foreclosed real estate and certain other assets and required the Company to record loss share assets and liabilities that were measured separately from the loan portfolios because they were not contractually embedded in the loans and were not transferable with the loans should the Company have chosen to dispose of them. Fair values at the acquisition dates were estimated based on projected cash flows available for loss share based on the credit adjustments estimated for each loan pool and the loss share percentages. The loss share assets and liabilities were recorded as FDIC indemnification assets and other liabilities, respectively, on the Consolidated Statements of Condition as of dates covered by loss share agreements. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses reduced the FDIC indemnification assets. Reductions to expected losses, to the extent such reductions to expected losses were the result of an improvement to the actual or expected cash flows from the covered assets, also reduced the FDIC indemnification assets and, if necessary, increased any loss share liability when necessary reductions exceeded the current value of the FDIC indemnification assets. In accordance with the clawback provision noted above, the Company was required to reimburse the FDIC when actual losses were less than certain thresholds established for each loss share agreement. The balance of these estimated reimbursements in accordance with clawback provisions and any related amortization were adjusted periodically for changes in the expected losses on covered assets. On the Consolidated Statements of Condition as of dates subject to loss share agreements, estimated reimbursements from clawback provisions were recorded as a reduction to the FDIC indemnification asset or, if necessary, an increase to the loss share liability, which was included within accrued interest payable and other liabilities. In the second quarter of 2017, the Company recorded a $4.9 million reduction to the estimated loss share liability as a result of an adjustment related to such clawback provisions. Although these assets were contractual receivables from the FDIC and these liabilities were contractual payables to the FDIC, there were no contractual interest rates. Additional expected losses, to the extent such expected losses resulted in recognition of an allowance for covered loan losses, increased the FDIC indemnification asset or reduced the FDIC indemnification liability. The corresponding amortization was recorded as a component of non-interest income on the Consolidated Statements of Income during periods covered by the loss share agreements. The following table summarizes the activity in the Company’s FDIC loss share liability during the periods indicated: Year Ended December 31, (Dollars in thousands) 2017 Balance at beginning of period $ 16,701 Reductions from reimbursable expenses (291 ) Amortization 1,044 Changes in expected reimbursements from the FDIC for changes in expected credit losses (1,658 ) Resolution through payments paid to the FDIC and termination of loss share agreements (15,796 ) Balance at end of period $ — On October 16, 2017, the Company entered into agreements with the FDIC that terminated all existing loss share agreements with the FDIC. Under the terms of the agreements, the Company made a net payment of $15.2 million to the FDIC as consideration for the early termination of the loss share agreements. The Company recorded a pre-tax gain of approximately $0.4 million to write off the remaining loss share asset, relieve the claw-back liability and recognize the payment to the FDIC. Wealth Management Acquisitions On December 14, 2018. the Company acquired Elektra, the parent company of CDEC. CDEC is a provider of Qualified Intermediary services (as defined by U.S. Treasury regulations) for taxpayers seeking to structure tax-deferred like-kind exchanges under Internal Revenue Code Section 1031. CDEC has successfully facilitated more than 8,000 like-kind exchanges in the past decade for taxpayers nationwide. These transactions typically generate customer deposits during the period following the sale of the property until such proceeds are used to purchase a replacement property. The Company recorded goodwill of $37.6 million on the acquisition. Mortgage Banking Acquisitions On January 4, 2018, the Company acquired Veterans First with assets including mortgage-servicing-rights on approximately 10,000 loans, totaling an estimated $1.6 billion in unpaid principal balance. The Company recorded goodwill of $9.1 million on the acquisition. On February 14, 2017, the Company acquired certain assets and assumed certain liabilities of the mortgage banking business of American Homestead Mortgage, LLC ("AHM"). The Company recorded goodwill of $1.0 million on the acquisition. PCI loans Purchased loans acquired in a business combination are recorded at estimated fair value on their purchase date. For PCI loans, expected future cash flows at the purchase date in excess of the fair value of loans are recorded as interest income over the life of the loans if the timing and amount of the future cash flows is reasonably estimable (“accretable yield”). The difference between contractually required payments and the cash flows expected to be collected at acquisition is referred to as the non-accretable difference and represents probable losses in the portfolio. In determining the acquisition date fair value of PCI loans, and in subsequent accounting, the Company aggregates these purchased loans into pools of loans by common risk characteristics, such as credit risk rating and loan type. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. Subsequent decreases to the expected cash flows will result in a provision for loan losses. The Company purchased a portfolio of life insurance premium finance receivables in 2009. These purchased life insurance premium finance receivables are valued on an individual basis. If credit related conditions deteriorate, an allowance related to these loans will be established as part of the provision for credit losses. See Note 4, “Loans,” for more information on loans acquired with evidence of credit quality deterioration since origination.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets A summary of the Company’s goodwill assets by business segment is presented in the following table: (Dollars in thousands) January 1, Goodwill Impairment Goodwill Adjustments December 31, 2018 Community banking $ 429,520 $ 35,565 $ — $ — $ 465,085 Specialty finance 40,250 — — (1,907 ) 38,343 Wealth management 32,114 37,599 — — 69,713 Total $ 501,884 $ 73,164 $ — $ (1,907 ) $ 573,141 The community banking segment's goodwill increased $35.6 million in 2018 as a result of the acquisition of CSC and Veterans First. The specialty finance segment's goodwill decreased $1.9 million in 2018 as a result of foreign currency translation adjustments related to the Canadian acquisitions. The wealth management segment's goodwill increased $37.6 million in 2018 as a result of the acquisition of CDEC. A summary of finite-lived intangible assets as of the dates shown and the expected amortization as of December 31, 2018 is as follows: December 31, (Dollars in thousands) 2018 2017 Community banking segment: Core deposit and other intangibles: Gross carrying amount $ 55,366 $ 37,272 Accumulated amortization (29,406 ) (25,427 ) Net carrying amount $ 25,960 $ 11,845 Trademark with indefinite lives: Carrying amount 5,800 — Total net carrying amount $ 31,760 $ 11,845 Specialty finance segment: Customer list intangibles: Gross carrying amount $ 1,958 $ 1,972 Accumulated amortization (1,436 ) (1,298 ) Net carrying amount $ 522 $ 674 Wealth management segment: Customer list and other intangibles: Gross carrying amount $ 20,430 $ 7,940 Accumulated amortization (3,288 ) (2,838 ) Net carrying amount $ 17,142 $ 5,102 Total other intangible assets, net $ 49,424 $ 17,621 Estimated amortization for the year-ended: 2019 $ 11,342 2020 9,582 2021 6,385 2022 4,957 2023 3,621 The core deposit intangibles recognized in connection with prior bank acquisitions are amortized over a ten -year period on an accelerated basis. The customer list intangibles recognized in connection with the purchase of life insurance premium finance assets in 2009 are being amortized over an 18 -year period on an accelerated basis while the customer list intangibles recognized in connection with prior acquisitions within the wealth management segment are being amortized over a period of up to ten -years on a straight-line basis. Total amortization expense associated with finite-lived intangibles in 2018 , 2017 and 2016 was $4.6 million , $4.4 million and $4.8 million , respectively.

Premises and Equipment, Net

Premises and Equipment, Net	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Premises and Equipment, Net	Premises and Equipment, Net A summary of premises and equipment at December 31, 2018 and 2017 is as follows: December 31, (Dollars in thousands) 2018 2017 Land $ 164,232 $ 147,704 Buildings and leasehold improvements 586,968 555,636 Furniture, equipment, and computer software 201,055 203,657 Construction in progress 16,179 6,962 $ 968,434 $ 913,959 Less: Accumulated depreciation and amortization 297,265 292,064 Total premises and equipment, net $ 671,169 $ 621,895 Depreciation and amortization expense related to premises and equipment totaled $33.2 million in 2018, $31.5 million in 2017 and $32.1 million in 2016 .

Deposits

Deposits	12 Months Ended
	Dec. 31, 2018
Deposits [Abstract]
Deposits	Deposits The following is a summary of deposits at December 31, 2018 and 2017 : (Dollars in thousands) 2018 2017 Balance: Non-interest bearing $ 6,569,880 $ 6,792,497 NOW and interest bearing demand deposits 2,897,133 2,315,055 Wealth management deposits 2,996,764 2,323,699 Money market 5,704,866 4,515,353 Savings 2,665,194 2,829,373 Time certificates of deposit 5,260,841 4,407,370 Total deposits $ 26,094,678 $ 23,183,347 Mix: Non-interest bearing 25 % 29 % NOW and interest bearing demand deposits 11 10 Wealth management deposits 12 10 Money market 22 20 Savings 10 12 Time certificates of deposit 20 19 Total deposits 100 % 100 % Wealth management deposits represent deposit balances of the Company’s subsidiary banks from brokerage customers of Wintrust Investments, CDEC, trust and asset management customers of the Company and brokerage customers from unaffiliated companies which have been placed into deposit accounts. The scheduled maturities of time certificates of deposit at December 31, 2018 and 2017 are as follows: (Dollars in thousands) 2018 2017 Due within one year $ 3,213,010 $ 3,167,220 Due in one to two years 1,251,446 969,130 Due in two to three years 710,836 127,548 Due in three to four years 47,979 98,952 Due in four to five years 37,563 44,206 Due after five years 7 314 Total time certificate of deposits $ 5,260,841 $ 4,407,370 The following table sets forth the scheduled maturities of time deposits in denominations of $100,000 or more at December 31, 2018 and 2017 : (Dollars in thousands) 2018 2017 Maturing within three months $ 682,940 $ 695,904 After three but within six months 667,079 614,963 After six but within 12 months 921,547 820,285 After 12 months 1,350,717 784,798 Total $ 3,622,283 $ 2,915,950 Time deposits in denominations of $250,000 or more were $1.6 billion and $1.3 billion at December 31, 2018 and 2017 , respectively.

Federal Home Loan Bank Advances

Federal Home Loan Bank Advances	12 Months Ended
	Dec. 31, 2018
Advances from Federal Home Loan Banks [Abstract]
Federal Home Loan Bank Advances	Federal Home Loan Bank Advances A summary of the outstanding FHLB advances at December 31, 2018 and 2017 , is as follows: (Dollars in thousands) 2018 2017 1.44% advance due January 2018 $ — $ 250,000 1.49% advance due February 2018 — 94,663 1.57% advance due June 2019 1,991 — 1.75% advance due June 2020 3,940 — 1.72% advance due June 2020 2,461 — 1.88% advance due June 2021 2,934 — 4.18% advance due February 2022 25,000 25,000 1.52% advance due March 2022 50,000 50,000 1.45% advance due May 2022 50,000 50,000 1.46% advance due May 2022 90,000 90,000 1.98% advance due January 2023 100,000 — 0.93% advance due January 2028 100,000 — Total FHLB advances $ 426,326 $ 559,663 FHLB advances consist of obligations of the banks and are collateralized by qualifying residential real estate and home equity loans and certain securities. The banks have arrangements with the FHLB whereby, based on available collateral, they could have borrowed an additional $2.8 billion at December 31, 2018 . FHLB advances are stated at par value of the debt adjusted for unamortized prepayment fees paid at the time of prior restructurings of FHLB advances and unamortized fair value adjustments recorded in connection with advances acquired through acquisitions and debt issuance costs. Unamortized prepayment fees are amortized as an adjustment to interest expense using the effective interest method. Approximately $365.0 million of the FHLB advances outstanding at December 31, 2018 , have varying put or call dates ranging from January 2019 to January 2020. At December 31, 2018 , the weighted average contractual interest rate on FHLB advances was 1.63% .

Subordinated Notes

Subordinated Notes	12 Months Ended
	Dec. 31, 2018
Subordinated Borrowings [Abstract]
Subordinated Notes	Subordinated Notes At December 31, 2018 , the Company had outstanding subordinated notes totaling $139.2 million compared to $139.1 million at December 31, 2017 . In 2014, the Company issued $140.0 million of subordinated notes receiving $139.1 million in proceeds, net of underwriting discount. The notes have a stated interest rate of 5.00% and mature in June 2024 . In connection with the issuance of subordinated notes in 2014, the Company incurred costs totaling $1.3 million . These costs are a direct deduction from the carrying amount of the subordinated notes and are amortized to interest expense using the effective interest method. At December 31, 2018, the unamortized balances of these costs were approximately $790,000 . These subordinated notes qualify as Tier II capital under the regulatory capital requirements, subject to restrictions.

Other Borrowings

Other Borrowings	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Other Borrowings	Other Borrowings The following is a summary of other borrowings at December 31, 2018 and 2017 : (Dollars in thousands) 2018 2017 Notes payable $ 144,461 $ 41,222 Short-term borrowings 50,593 17,209 Other 47,722 49,131 Secured borrowings 151,079 158,561 Total other borrowings $ 393,855 $ 266,123 Notes Payable On September 18, 2018, the Company established a $150.0 million term facility ("Term Facility"), which is part of a $200.0 million loan agreement ("Credit Agreement") with unaffiliated banks. The Credit Agreement consists of the Term Facility with an original outstanding balance of $150.0 million and a $50.0 million revolving credit facility ("Revolving Credit Facility"). At December 31, 2018, the Company had a notes payable balance of $144.5 million under the Term Facility. The Term Facility is stated at par of the current outstanding balance of the debt adjusted for unamortized costs paid by the Company in relation to the debt issuance. The Company was contractually required to borrow the entire amount of the Term Facility on September 18, 2018 and all such borrowings must be repaid by September 18, 2023. Beginning December 31, 2018, the Company is required to make quarterly payments of principal plus interest on the Term Facility. At December 31, 2018, the Company had no outstanding balance under the Revolving Credit Facility. As no outstanding balance exists on the Revolving Credit Facility, unamortized costs paid by the Company in relation to the issuance of this debt are classified in other assets on the Consolidated Statements of Condition. Borrowings under the Credit Agreement that are considered “Base Rate Loans” bear interest at a rate equal to the sum of (1) 50 basis points (in the case of a borrowing under the Revolving Credit Facility) or 75 basis points (in the case of a borrowing under the Term Facility) plus (2) the highest of (a) the federal funds rate plus 50 basis points, (b) the lender's prime rate, and (c) the Eurodollar Rate (as defined below) that would be applicable for an interest period of one month plus 100 basis points. Borrowings under the agreement that are considered “Eurodollar Rate Loans” bear interest at a rate equal to the sum of (1) 125 basis points (in the case of a borrowing under the Revolving Credit Facility) or 125 basis points (in the case of a borrowing under the Term Facility) plus (2) the LIBOR rate for the applicable period, as adjusted for statutory reserve requirements for eurocurrency liabilities (the “Eurodollar Rate”). A commitment fee is payable quarterly equal to 0.20% of the actual daily amount by which the lenders' commitment under the Revolving Credit Facility exceeded the amount outstanding under such facility. Borrowings under the Credit Agreement are secured by pledges of and first priority perfected security interests in the Company's equity interest in its bank subsidiaries and contain several restrictive covenants, including the maintenance of various capital adequacy levels, asset quality and profitability ratios, and certain restrictions on dividends and other indebtedness. At December 31, 2018, the Company was in compliance with all such covenants. The Revolving Credit Facility and the Term Facility are available to be utilized, as needed, to provide capital to fund continued growth at the Company’s banks and to serve as an interim source of funds for acquisitions, common stock repurchases or other general corporate purposes. In connection with the establishment of the Credit Agreement, all outstanding notes payable under a $150.0 million loan agreement with unaffiliated banks dated December 15, 2014 (as subsequently amended) were paid in full. This loan agreement consisted of a term facility with an original outstanding balance of $75.0 million and a $75.0 million revolving credit facility. The Company had a balance under this loan agreement of $41.2 million at December 31, 2017. Short-term Borrowings Short-term borrowings include securities sold under repurchase agreements and federal funds purchased. These borrowings totaled $50.6 million and $17.2 million at December 31, 2018 and 2017, respectively. At December 31, 2018 and 2017, securities sold under repurchase agreements represent $ 50.6 million and $17.2 million , respectively, of customer sweep accounts in connection with master repurchase agreements at the banks. The Company records securities sold under repurchase agreements at their gross value and does not offset positions on the Consolidated Statements of Condition. As of December 31, 2018, the Company had pledged securities related to its customer balances in sweep accounts of $62.8 million . Securities pledged for customer balances in sweep accounts and short-term borrowings from brokers are maintained under the Company’s control and consist of U.S. Government agency and mortgage-backed securities. These securities are included in the available-for-sale and held-to-maturity securities portfolios as reflected on the Company’s Consolidated Statements of Condition. The following is a summary of these securities pledged as of December 31, 2018 disaggregated by investment category and maturity, and reconciled to the outstanding balance of securities sold under repurchase agreements: (Dollars in thousands) Overnight Sweep Collateral Available-for-sale securities pledged Mortgage-backed securities $ 21,059 Held-to-maturity securities pledged U.S. Government agencies 41,723 Total collateral pledged $ 62,782 Excess collateral 12,189 Securities sold under repurchase agreements $ 50,593 Other Borrowings Other borrowings at December 31, 2018 and 2017 represent a fixed-rate promissory note issued by the Company in June 2017 (“Fixed-Rate Promissory Note”) related to and secured by two office buildings owned by the Company, and non-recourse notes issued by the Company to other banks related to certain capital leases. At December 31, 2018 , the Fixed-Rate Promissory Note had a balance of $47.7 million . Under the Fixed-Rate Promissory Note, the Company will make monthly principal payments and pay interest at a fixed rate of 3.36% until maturity on June 30, 2022 . The Fixed-Rate Promissory Note contains several restrictive covenants, including the maintenance of various capital adequacy levels, asset quality and profitability ratios, and certain restrictions on dividends and other indebtedness. At December 31, 2018, the Company was in compliance with all such covenants. A previous fixed-rate promissory note with an unrelated creditor related to and secured by an office building owned by the Company was paid off upon the Company's issuance of the Fixed-Rate Promissory Note. Additionally, at December 31, 2017, other borrowings included non-recourse notes related to certain capital leases totaling $151,000 . Secured Borrowings Secured borrowings at December 31, 2018 primarily represents transactions to sell an undivided co-ownership interest in all receivables owed to the Company's subsidiary, FIFC Canada. In December 2014, FIFC Canada sold such interest to an unrelated third party in exchange for a cash payment of approximately C$150 million pursuant to a receivables purchase agreement (“Receivables Purchase Agreement”). The Receivables Purchase Agreement was amended in December 2015, extending the maturity date from December 15, 2015 to December 15, 2017 . Additionally, at that time, the unrelated third party paid an additional C$10 million , which increased the total payments to C$160 million . The Receivables Purchase Agreement was again amended in December 2017, extending the maturity date from December 15, 2017 to December 16, 2019. Additionally, at that time, the unrelated third party paid an additional C$10 million , which increased the total payments to C$170 million . In June 2018, the unrelated third party paid an additional C$20 million , which increased the total payments to C$190 million . These transactions were not considered sales of receivables and, as such, related proceeds received are reflected on the Company’s Consolidated Statements of Condition as a secured borrowing owed to the unrelated third party, net of unamortized debt issuance costs, and translated to the Company’s reporting currency as of the respective date. At December 31, 2018, the translated balance of the secured borrowing totaled $139.3 million compared to $135.1 million at December 31, 2017. Additionally, the interest rate under the Receivables Purchase Agreement at December 31, 2018 was 2.936% . The remaining $11.8 million within secured borrowings at December 31, 2018 represents other sold interests in certain loans by the Company that were not considered sales and, as such, related proceeds received are reflected on the Company’s Consolidated Statements of Condition as a secured borrowing owed to the various unrelated third parties.

Junior Subordinated Debentures

Junior Subordinated Debentures	12 Months Ended
	Dec. 31, 2018
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust [Abstract]
Junior Subordinated Debentures	Junior Subordinated Debentures As of December 31, 2018 , the Company owned 100% of the common securities of eleven trusts, Wintrust Capital Trust III, Wintrust Statutory Trust IV, Wintrust Statutory Trust V, Wintrust Capital Trust VII, Wintrust Capital Trust VIII, Wintrust Capital Trust IX, Northview Capital Trust I, Town Bankshares Capital Trust I, First Northwest Capital Trust I, Suburban Illinois Capital Trust II, and Community Financial Shares Statutory Trust II (the “Trusts”) set up to provide long- term financing. The Northview, Town, First Northwest, Suburban and Community Financial Shares capital trusts were acquired as part of the acquisitions of Northview Financial Corporation, Town Bankshares, Ltd., First Northwest Bancorp, Inc., Suburban and CFIS, respectively. The Trusts were formed for purposes of issuing trust preferred securities to third-party investors and investing the proceeds from the issuance of the trust preferred securities and common securities solely in junior subordinated debentures issued by the Company (or assumed by the Company in connection with an acquisition), with the same maturities and interest rates as the trust preferred securities. The junior subordinated debentures are the sole assets of the Trusts. In each Trust, the common securities represent approximately 3% of the junior subordinated debentures and the trust preferred securities represent approximately 97% of the junior subordinated debentures. In January 2016, the Company acquired $15.0 million of the $40.0 million of trust preferred securities issued by Wintrust Capital Trust VIII from a third-party investor. The purchase effectively extinguished $15.0 million of junior subordinated debentures related to Wintrust Capital Trust VIII and resulted in a $4.3 million gain from the early extinguishment of debt. The Trusts are reported in the Company’s consolidated financial statements as unconsolidated subsidiaries. Accordingly, in the Consolidated Statements of Condition, the junior subordinated debentures issued by the Company to the Trusts are reported as liabilities and the common securities of the Trusts, all of which are owned by the Company, are included in investment securities. The following table provides a summary of the Company’s junior subordinated debentures as of December 31, 2018 and 2017 . The junior subordinated debentures represent the par value of the obligations owed to the Trusts. Common Securities Trust Preferred Securities Junior Subordinated Debentures Rate Structure Contractual rate at 12/31/2018 Maturity Date Earliest Redemption Date (Dollars in thousands) 2018 2017 Issue Date Wintrust Capital Trust III $ 774 $ 25,000 $ 25,774 $ 25,774 L+3.25 5.69 % 04/2003 04/2033 04/2008 Wintrust Statutory Trust IV 619 20,000 20,619 20,619 L+2.80 5.60 12/2003 12/2033 12/2008 Wintrust Statutory Trust V 1,238 40,000 41,238 41,238 L+2.60 5.40 05/2004 05/2034 06/2009 Wintrust Capital Trust VII 1,550 50,000 51,550 51,550 L+1.95 4.74 12/2004 03/2035 03/2010 Wintrust Capital Trust VIII 1,238 25,000 26,238 26,238 L+1.45 4.25 08/2005 09/2035 09/2010 Wintrust Capital Trust IX 1,547 50,000 51,547 51,547 L+1.63 4.42 09/2006 09/2036 09/2011 Northview Capital Trust I 186 6,000 6,186 6,186 L+3.00 5.54 08/2003 11/2033 08/2008 Town Bankshares Capital Trust I 186 6,000 6,186 6,186 L+3.00 5.54 08/2003 11/2033 08/2008 First Northwest Capital Trust I 155 5,000 5,155 5,155 L+3.00 5.80 05/2004 05/2034 05/2009 Suburban Illinois Capital Trust II 464 15,000 15,464 15,464 L+1.75 4.54 12/2006 12/2036 12/2011 Community Financial Shares Statutory Trust II 109 3,500 3,609 3,609 L+1.62 4.41 06/2007 09/2037 06/2012 Total $ 253,566 $ 253,566 4.94 % The junior subordinated debentures totaled $253.6 million at December 31, 2018 and 2017 . The interest rates on the variable rate junior subordinated debentures are based on the three-month LIBOR rate and reset on a quarterly basis. At December 31, 2018 , the weighted average contractual interest rate on the junior subordinated debentures was 4.94% . Distributions on the common and preferred securities issued by the Trusts are payable quarterly at a rate per annum equal to the interest rates being earned by the Trusts on the junior subordinated debentures. Interest expense on the junior subordinated debentures is deductible for income tax purposes. The Company has guaranteed the payment of distributions and payments upon liquidation or redemption of the trust preferred securities, in each case to the extent of funds held by the Trusts. The Company and the Trusts believe that, taken together, the obligations of the Company under the guarantees, the junior subordinated debentures, and other related agreements provide, in the aggregate, a full, irrevocable and unconditional guarantee, on a subordinated basis, of all of the obligations of the Trusts under the trust preferred securities. Subject to certain limitations, the Company has the right to defer the payment of interest on the junior subordinated debentures at any time, or from time to time, for a period not to exceed 20 consecutive quarters. The trust preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the junior subordinated debentures at maturity or their earlier redemption. The junior subordinated debentures are redeemable in whole or in part prior to maturity at any time after the earliest redemption dates shown in the table, and earlier at the discretion of the Company if certain conditions are met, and, in any event, only after the Company has obtained Federal Reserve Bank ("FRB") approval, if then required under applicable guidelines or regulations. At December 31, 2018, the Company included $245.5 million of the junior subordinated debentures, net of common securities, in Tier 2 regulatory capital.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers As of January 1, 2018, the Company adopted ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606),” and all subsequent updates issued to clarify and improve specific areas of ASU 2014-09. The Company elected to adopt the new guidance using the modified retrospective approach applied to all contracts as of the date of initial application at January 1, 2018. Under the modified retrospective approach, the Company recognized no cumulative effect adjustment to the opening balance of retained earnings at the date of initial application. Disaggregation of Revenue As certain significant revenue sources related to financial instruments such as interest income are considered not in-scope, ASU 2014-09 did not have a significant impact on the Company's consolidated financial statements. The following table presents revenue from contracts with customers, considered in-scope under ASU 2014-09, disaggregated by the revenue source: (Dollars in thousands) Years Ended Revenue from contracts with customers Location in income statement December 31, December 31, December 31, Brokerage and insurance product commissions Wealth management $ 22,391 $ 22,863 $ 25,519 Trust Wealth management 13,263 12,547 11,993 Asset management Wealth management 55,309 46,356 38,506 Total wealth management 90,963 81,766 76,018 Mortgage broker fees Mortgage banking 1,188 1,565 2,834 Service charges on deposit accounts Service charges on deposit accounts 36,404 34,513 31,210 Administrative services Other non-interest income 4,625 4,165 4,409 Card related fees Other non-interest income 7,441 5,858 5,495 Other deposit related fees Other non-interest income 11,892 11,127 9,555 Wealth Management Revenue Wealth management revenue is comprised of brokerage and insurance product commissions, managed money fees and trust and asset management revenue of the Company's four wealth management subsidiaries: Wintrust Investments, Great Lakes Advisors, CTC and CDEC. All wealth management revenue is recognized in the wealth management segment. Brokerage and insurance product commissions consists primarily of commissions earned from trade execution services on behalf of customers and from selling mutual funds, insurance and other investment products to customers. For trade execution services, the Company recognizes commissions and receives payment from the brokerage customers at the point of transaction execution. Commissions received from the investment or insurance product providers are recognized at the point of sale of the product. The Company also receives trail and other commissions from providers for certain plans. These are generally based on qualifying account values and are recognized once the performance obligation, specific to each provider, is satisfied on a monthly, quarterly or annual basis. Trust revenue is earned primarily from trust and custody services that are generally performed over time as well as fees earned on funds held during the facilitation of tax-deferred like-kind exchange transactions. Revenue is determined periodically based on a schedule of fees applied to the value of each customer account using a time-elapsed method to measure progress toward complete satisfaction of the performance obligation. Fees are typically billed on a calendar month or quarter basis in advance or in arrears depending upon the contract. Upfront fees received related to the facilitation of tax-deferred like-kind exchange transactions are deferred until the transaction is completed. Additional fees earned for certain extraordinary services performed on behalf of the customers are recognized when the service has been performed. Asset management revenue is earned from money management and advisory services that are performed over time. Revenue is based primarily on the market value of assets under management or administration using a time-elapsed method to measure progress toward complete satisfaction of the performance obligation. Fees are typically billed on a calendar month or quarter basis in advance or in arrears depending upon the contract. Certain programs provide the customer with an option of paying fees as a percentage of the account value or incurring commission charges for each trade similar to brokerage and insurance product commissions. Trade commissions and any other fees received for additional services are recognized at a point in time once the performance obligation is satisfied. Mortgage Broker Fees For customers desiring a mortgage product not currently offered by the Company, the Company may refer such customers and, with permission, direct such customers' applications to certain third party mortgage brokers. Mortgage broker fees are received from these brokers for such customer referrals upon settlement of the underlying mortgage. The Company's entitlement to the consideration is contingent on the settlement of the mortgage which is highly susceptible to factors outside of the Company's influence, such as the third party broker's underwriting requirements. Also, the uncertainty surrounding the consideration could be resolved in varying lengths of time, dependent upon the third party brokers. Therefore, mortgage broker fees are recognized at the settlement of the underlying mortgage when the consideration is received. Broker fees are recognized in the community banking segment. Service Charges on Deposit Accounts Service charges on deposit accounts include fees charged to deposit customers for various services, including account analysis services, and are based on factors such as the size and type of customer, type of product and number of transactions. The fees are based on a standard schedule of fees and, depending on the nature of the service performed, the service is performed at a point in time or over a period of a month. When the service is performed at a point in time, the Company recognizes and receives revenue when the service has been performed. When the service is performed over a period of a month, the Company recognizes and receives revenue in the month the service has been performed. Service charges on deposit accounts are recognized in the community banking segment. Administrative Services Administrative services revenue is earned from providing outsourced administrative services, such as data processing of payrolls, billing and cash management services, to temporary staffing service clients located throughout the United States. Fees are charged periodically (typically a payroll cycle) and computed in accordance with the contractually determined rate applied to the total gross billings administered for the period. The revenue is recognized over the period using a time-elapsed method to measure progress toward complete satisfaction of the performance obligation. Other fees are charged on a per occurrence basis as the service is provided in the billing cycle. The Company has certain contracts with customers to perform outsourced administrative services and short-term accounts receivable financing. For these contracts, the total fee is allocated between the administrative services revenue and interest income during the client onboarding process based on the specific client and services provided. Administrative services revenue is recognized in the specialty finance segment. Card and Deposit Related Fees Card related fees include interchange and merchant revenue, and fees related to debit and credit cards. Interchange revenue is related to the Company issued debit cards. Other deposit related fees primarily include pay by phone processing fees, ATM and safe deposit box fees, check order charges and foreign currency related fees. Card and deposit related fees are generally based on volume of transactions and are recognized at the point in time when the service has been performed. For any consideration that is constrained, the revenue is recognized once the uncertainty is known. Upfront fees received from certain contracts are recognized on a straight line basis over the term of the contract. Card and deposit related fees are recognized in the community banking segment. Contract Balances The following table provides information about contract assets, contract liabilities and receivables from contracts with customers: (Dollars in thousands) December 31, December 31, Contract assets $ — $ — Contract liabilities $ 1,727 $ 1,706 Mortgage broker fees receivable $ 44 $ 69 Administrative services receivable 275 — Wealth management receivable 13,610 8,102 Card related fees receivable — 202 Total receivables from contracts with customer $ 13,929 $ 8,373 Contract liabilities represent upfront fees that the Company received at inception of certain contracts. The revenue recognized that was included in the contract liability balance at beginning of the period totaled $369,000 and $359,000 for the years ended December 31, 2018 and 2017, respectively. Receivables are recognized in the period the Company provides services when the Company's right to consideration is unconditional. Card related fee receivable is the result of volume based fee that the Company receives from a customer on an annual basis in the second quarter of each year. Payment terms on other invoiced amounts are typically 30 days or less. Contract liabilities and receivables from contracts with customers are included within the accrued interest payable and other liabilities and accrued interest receivable and other assets line items, respectively, in the Consolidated Statements of Condition. Transaction price allocated to the remaining performance obligations For contracts with an original expected length of more than one year, the following table presents the estimated future timing of recognition of upfront fees related to card and deposit related fees. These upfront fees represent performance obligations that are unsatisfied or partially unsatisfied at the end of the reporting period. (Dollars in thousands) Estimated—2019 $ 759 Estimated—2020 369 Estimated—2021 303 Estimated—2022 153 Estimated—2023 143 Total $ 1,727 Practical Expedients and Exemptions The Company does not adjust the promised amount of consideration for the effects of a significant financing component if the Company expects, at contract inception, that the period between when the Company transfers a promised service to a customer and when the customer pays for that services is one year or less. The Company recognizes the incremental costs of obtaining a contract as an expense when incurred if the amortization period of the asset that the entity otherwise would have recognized is one year or less.

Minimum Lease Commitments

Minimum Lease Commitments	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Minimum Lease Commitments	Minimum Lease Commitments The Company occupies certain facilities under operating lease agreements. Gross rental expense related to the Company’s operating leases were $21.2 million in 2018, $17.7 million in 2017, and $17.4 million in 2016 . The Company also leases certain owned premises and receives rental income from such lease agreements. Gross rental income related to the Company’s buildings totaled $11.8 million , $9.8 million and $8.9 million , in 2018, 2017 and 2016 , respectively. The approximate minimum annual gross rental payments and gross rental receipts under noncancelable agreements for office space with remaining terms in excess of one year as of December 31, 2018 , are as follows (in thousands): Payments Receipts 2019 $ 15,106 $ 7,533 2020 16,406 5,576 2021 15,116 5,081 2022 14,253 3,636 2023 13,201 2,117 2024 and thereafter 131,615 5,233 Total minimum future amounts $ 205,697 $ 29,176

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense (benefit) for the years ended December 31, 2018 , 2017 and 2016 is summarized as follows: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Current income taxes: Federal $ 44,266 $ 54,977 $ 98,272 State 18,349 12,852 20,041 Foreign (872 ) 1,243 (10 ) Total current income taxes $ 61,743 $ 69,072 $ 118,303 Deferred income taxes: Federal $ 40,500 $ 51,668 $ 4,464 State 11,705 10,403 (14 ) Foreign 3,019 1,172 2,226 Total deferred income taxes $ 55,224 $ 63,243 $ 6,676 Total income tax expense $ 116,967 $ 132,315 $ 124,979 The Company's income before income taxes in 2018 , 2017 and 2016 includes $5.3 million , $7.8 million and $7.0 million , respectively, of foreign income attributable to its Canadian subsidiary. The tax effects of certain transactions are recorded directly to shareholders' equity rather than income tax expense. The tax effect of fair value adjustments on securities available-for-sale and derivative instruments in cash flow hedges are recorded directly to shareholders' equity as part of other comprehensive income (loss) and are reflected on the Consolidated Statements of Comprehensive Income. In addition, a tax benefit of $230,000 , related to stock-based compensation, reflecting the excess of realized tax benefits over expected tax benefits, was recorded directly to shareholders' equity in 2016. Beginning in 2017, excess tax benefits on stock-based compensation were recorded in tax expense. The tax effect of unrealized gains and losses on certain foreign currency transactions is also recorded in shareholders' equity as part of other comprehensive income (loss). A reconciliation of the differences between taxes computed using the statutory Federal income tax rate and actual income tax expense is as follows: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Income tax expense using the statutory Federal income tax rate of 21% in 2018, and 35% in 2017 and 2016, on income before income taxes $ 96,628 $ 136,499 $ 116,149 Increase (decrease) in tax resulting from: Tax-exempt interest, net of interest expense disallowance (3,869 ) (4,658 ) (3,634 ) State taxes, net of federal tax benefit 23,584 15,115 13,017 Income earned on bank owned life insurance (1,002 ) (1,167 ) (1,198 ) Excess tax benefits on share based compensation (3,107 ) (5,470 ) — Enactment of Tax Cuts and Jobs Act Re-measurement of net deferred tax liabilities (1,209 ) (10,402 ) — Transition tax on deferred foreign earnings — 2,850 — Meals, entertainment and related expenses 1,840 1,710 1,439 FDIC insurance expense 1,832 — — Non-deductible compensation expense 1,366 55 77 Foreign subsidiary, net 1,591 (271 ) (264 ) Tax benefits related to tax credit investments, net (656 ) (698 ) (572 ) Other, net (31 ) (1,248 ) (35 ) Income tax expense $ 116,967 $ 132,315 $ 124,979 In 2017, the Company recognized a provisional tax benefit of $7.6 million to reflect the impact of enactment of the Tax Act. In the third quarter 2018, the Company finalized the provisional amount and recorded an additional net tax benefit of $1.2 million as provided in the SEC issued Staff Accounting Bulletin SAB 118. The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and liabilities at December 31, 2018 and 2017 are as follows: (Dollars in thousands) 2018 2017 Deferred tax assets: Allowance for credit losses $ 40,342 $ 36,442 Deferred compensation 22,363 12,310 Net unrealized losses on securities included in other comprehensive income 15,430 7,465 Stock-based compensation 7,544 6,898 Federal net operating loss carryforward 5,348 3,063 Loans 4,540 4,943 Other real estate owned 2,429 4,019 AMT credit carryforward 1,395 1,199 Nonaccrued interest 1,357 983 Mortgage banking recourse obligation 632 722 Other 3,744 2,307 Total gross deferred tax assets 105,124 80,351 Deferred tax liabilities: Equipment leasing 90,306 42,681 Premises and equipment 28,517 23,211 Capitalized servicing rights 16,663 8,916 Goodwill and intangible assets 12,921 7,619 Deferred loan fees and costs 3,446 3,531 Net unrealized gains on derivatives included in other comprehensive income 2,863 3,197 Fair value adjustments on loans 2,833 3,143 Other 5,295 3,433 Total gross deferred liabilities 162,844 95,731 Net deferred tax liabilities $ (57,720 ) $ (15,380 ) Management has determined that a valuation allowance is not required for the deferred tax assets at December 31, 2018 because it is more likely than not that these assets could be realized through future reversals of existing taxable temporary differences, tax planning strategies and future taxable income. This conclusion is based on the Company's historical earnings, its current level of earnings and prospects for continued growth and profitability. The Company has a Federal alternative minimum tax (“AMT”) credit carryforward of $1.4 million which is subject to IRC Section 383 annual limitation. The AMT credit has no expiration date and pursuant to the Tax Act will be fully refundable by 2021 . The Company has a Federal net operating loss (“NOL”) carryforward of $25.5 million that begins to expire in 2029 through 2037 and is subject to IRC Section 382 annual limitation. The AMT credit and the NOL carryforwards were a result of acquisitions. The Company accounts for uncertainties in income taxes in accordance with ASC 740, Income Taxes. The following table provides a reconciliation of the beginning and ending amounts of gross unrecognized tax benefits: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Unrecognized tax benefits at beginning of year $ 10,821 $ 11,626 $ — Gross increases for tax positions taken in current period — — — Gross increases (decreases) for positions taken in prior periods 717 (805 ) 11,626 Unrecognized tax benefits at end of the year $ 11,538 $ 10,821 $ 11,626 At December 31, 2018 , the Company had $9.3 million of unrecognized tax benefits related to uncertain tax positions that, if recognized, would impact the effective tax rate. Interest and penalties on unrecognized tax positions are recorded in income tax expense. Total interest income accrued at December 31, 2018 and 2017 on unrecognized tax benefits was $1.1 million and $921,000 , respectively, net of tax effect. Interest and penalties are included in the liability for uncertain tax positions, but are not included in the unrecognized tax benefits rollforward presented above. The Company does not expect the total amount of unrecognized tax benefits to significantly increase or decrease in the next twelve months. The Company and its subsidiaries are subject to U.S. federal income tax as well as income tax in numerous state jurisdictions and in Canada. In the ordinary course of business we are routinely subject to audit by the taxing authorities of these jurisdictions. Currently, the Company's U.S. federal income tax returns are open and subject to audit for the 2015 tax return year forward, and in general, the Company's state income tax returns are open and subject to audit from the 2015 tax return year forward, subject to individual state statutes of limitation. The Company's Canadian subsidiary's Canadian income tax returns are also subject to audit for the 2015 tax return year forward.

Stock Compensation Plans and Ot

Stock Compensation Plans and Other Employee Benefit Plans	12 Months Ended
	Dec. 31, 2018
Share-based Compensation [Abstract]
Stock Compensation Plans and Other Employee Benefit Plans	Stock Compensation Plans and Other Employee Benefit Plans Stock Incentive Plan In May 2015, the Company’s shareholders approved the 2015 Stock Incentive Plan (“the 2015 Plan”) which provides for the issuance of up to 5,485,000 shares of common stock. The 2015 Plan replaced the 2007 Stock Incentive Plan (“the 2007 Plan”), which replaced the 1997 Stock Incentive Plan (“the 1997 Plan”). The 2015 Plan, the 2007 Plan and the 1997 Plan are collectively referred to as “the Plans.” The 2015 Plan has substantially similar terms to the 2007 Plan and the 1997 Plan. Awards granted under the Plans for which common shares are not issued by reason of cancellation, forfeiture, lapse of such award or settlement of such award in cash, are again available under the 2015 Plan. All grants made after the approval of the 2015 Plan have been made pursuant to the 2015 Plan. As of December 31, 2018 , approximately 3.4 million shares were available for future grants (assuming the maximum number of shares are issued for the performance awards outstanding.) The Plans cover substantially all employees of Wintrust. The Compensation Committee of the Board of Directors administers all stock-based compensation programs and authorizes all awards granted pursuant to the Plans. The Plans permit the grant of incentive stock options, non-qualified stock options, stock appreciation rights, stock awards, restricted share or unit awards, performance awards and other incentive awards valued in whole or in part by reference to the Company’s common stock, all on a stand-alone, combination or tandem basis. The Company historically awarded stock-based compensation in the form of time-vested nonqualified stock options and time-vested restricted share unit awards (“restricted shares”). In general, the grants of options provide for the purchase shares of the Company’s common stock at the fair market value of the stock on the date the options are granted. Options under the 2015 Plan and the 2007 Plan generally vest ratably over periods of three to five years and have a maximum term of seven years from the date of grant. Restricted shares entitle the holders to receive, at no cost, shares of the Company’s common stock. Restricted shares generally vest over periods of one to five years from the date of grant. Beginning in 2011, the Company has awarded annual grants under the Long-Term Incentive Program (“LTIP”), which is administered under the Plans. The LTIP is designed in part to align the interests of management with interests of shareholders, foster retention, create a long-term focus based on sustainable results and provide participants a target long-term incentive opportunity. It is anticipated that LTIP awards will continue to be granted annually. LTIP grants to date have consisted of time-vested nonqualified stock options and performance-based stock and performance-based cash awards. Stock options granted under the LTIP have a term of seven years and will generally vest equally over three years based on continued service. Performance-based stock and cash awards granted under the LTIP are contingent upon the achievement of pre-established long-term performance goals set in advance by the Compensation Committee over a three -year period. These performance awards are granted at a target level, and based on the Company’s achievement of the pre-established long-term goals, the actual payouts can range from 0% to 150% of the target award. The awards typically vest in the quarter after the end of the performance period upon certification of the payout by the Compensation Committee of the Board of Directors. Holders of performance-based stock awards are entitled to receive, at no cost, the shares earned based on the achievement of the pre-established long-term goals. Holders of restricted share awards and performance-based stock awards received under the Plans are not entitled to vote or receive cash dividends (or cash payments equal to the cash dividends) on the underlying common shares until the awards are vested and issued. Shares that are vested but are not issuable pursuant to deferred compensation arrangements accrue additional shares based on the value of dividends otherwise paid. Except in limited circumstances, unvested awards granted under the Plans are canceled upon termination of employment without any payment of consideration by the Company. Stock-based compensation is measured as the fair value of an award on the date of grant, and the measured cost is recognized over the period which the recipient is required to provide service in exchange for the award. The fair values of restricted share and performance-based stock awards are determined based on the average of the high and low trading prices on the grant date, and the fair value of stock options is estimated using a Black-Scholes option-pricing model that utilizes the assumptions outlined in the following table. Option-pricing models require the input of highly subjective assumptions and are sensitive to changes in the option’s expected life and the price volatility of the underlying stock, which can materially affect the fair value estimate. Options granted since the inception of the LTIP in 2011 were primarily granted as LTIP awards. Expected life of the options granted since the inception of the LTIP awards has been based on the safe harbor rule of the SEC Staff Accounting Bulletin No. 107 “Share-Based Payment” as the Company believes historical exercise data may not provide a reasonable basis to estimate the expected term of these options. Expected stock price volatility is based on historical volatility of the Company’s common stock, which correlates with the expected life of the options, and the risk-free interest rate is based on comparable U.S. Treasury rates. Management reviews and adjusts the assumptions used to calculate the fair value of an option on a periodic basis to better reflect expected trends. The following table presents the weighted average assumptions used to determine the fair value of options granted in the year ended December 31, 2016 . No options were granted in the years ended December 31, 2018 and 2017. 2016 Expected dividend yield 0.9 % Expected volatility 25.2 % Risk-free rate 1.3 % Expected option life (in years) 4.5 Stock based compensation is recognized based on the number of awards that are ultimately expected to vest. Forfeitures are estimated based on historical forfeiture experience. For performance-based stock awards, an estimate is made of the number of shares expected to vest as a result of actual performance against the performance criteria to determine the amount of compensation expense to be recognized. The estimate is reevaluated quarterly and total compensation expense is adjusted for any change in the current period. Stock-based compensation expense recognized in the Consolidated Statements of Income was $13.5 million , $12.9 million and $9.3 million and the related tax benefits were $3.1 million , $5.1 million and $3.7 million in 2018 , 2017 and 2016 , respectively. A summary of the Plans’ stock option activity for the years ended December 31, 2018 , 2017 and 2016 is as follows: Stock Options Common Shares Weighted Average Strike Price Remaining Contractual Term (1) Intrinsic Value (2) ($000) Outstanding at January 1, 2016 1,551,734 $ 41.32 Granted 562,166 41.04 Exercised (313,900 ) 37.71 Forfeited or canceled (101,088 ) 48.00 Outstanding at December 31, 2016 1,698,912 $ 41.50 4.6 $ 52,790 Exercisable at December 31, 2016 703,892 $ 39.62 3.4 $ 23,195 Outstanding at January 1, 2017 1,698,912 $ 41.50 Granted — — Exercised (593,459 ) 40.57 Forfeited or canceled (20,697 ) 42.83 Outstanding at December 31, 2017 1,084,756 $ 41.98 4.0 $ 43,817 Exercisable at December 31, 2017 562,810 $ 41.82 3.3 $ 22,820 Outstanding at January 1, 2018 1,084,756 $ 41.98 Granted — — Exercised (282,614 ) 41.25 Forfeited or canceled (7,128 ) 39.84 Outstanding at December 31, 2018 795,014 $ 42.25 3.1 $ 19,268 Exercisable at December 31, 2018 613,932 $ 42.54 3.1 $ 14,705 Vested or expected to vest at December 31, 2018 787,753 $ 42.26 3.1 $ 19,085 (1) Represents the weighted average contractual remaining life in years. (2) Aggregate intrinsic value represents the total pretax intrinsic value (i.e., the difference between the Company’s stock price at year end and the option exercise price, multiplied by the number of shares) that would have been received by the option holders if they had exercised their options on the last day of the year. Options with exercise prices above the year end stock price are excluded from the calculation of intrinsic value. The intrinsic value will change based on the fair market value of the Company’s stock. The weighted average per share grant date fair value of options granted during the years ended December 31, 2016 was $8.61 . The aggregate intrinsic value of options exercised during the years ended December 31, 2018 , 2017 and 2016 , was $13.3 million , $20.1 million and $5.8 million , respectively. The actual tax benefit realized for the tax deductions from option exercises totaled $3.5 million , $7.8 million and $2.3 million for 2018 , 2017 and 2016 , respectively. Cash received from option exercises under the Plans for the years ended December 31, 2018 , 2017 and 2016 was $11.7 million , $24.1 million and $11.8 million , respectively. A summary of the Plans’ restricted share activity for the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 2017 2016 Restricted Shares Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Outstanding at January 1 127,787 $ 53.33 133,425 $ 49.94 137,593 $ 49.63 Granted 35,654 84.36 16,552 73.16 18,022 46.01 Vested and issued (18,324 ) 54.31 (19,639 ) 47.13 (20,007 ) 44.91 Forfeited (1,854 ) 63.50 (2,551 ) 52.26 (2,183 ) 44.18 Outstanding at end of year 143,263 $ 60.80 127,787 $ 53.33 133,425 $ 49.94 Vested, but not issuable at end of year 90,520 $ 51.94 89,723 $ 51.64 89,050 $ 51.47 A summary of the 2007 Plan’s performance-based stock award activity, based on the target level of the awards, for the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 2017 2016 Performance Shares Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Outstanding at January 1 359,196 $ 54.37 298,180 $ 43.64 276,533 $ 43.01 Granted 134,380 88.27 145,853 72.60 118,084 41.02 Vested and issued (82,307 ) 44.39 (68,712 ) 46.85 (78,410 ) 37.90 Expired, canceled or forfeited (14,414 ) 60.05 (16,125 ) 52.98 (18,027 ) 41.83 Outstanding at end of year 396,855 $ 67.71 359,196 $ 54.37 298,180 $ 43.64 Vested, but deferred at year end 21,530 $ 43.54 108,143 $ 44.16 6,672 $ 37.98 At December 31, 2018, the maximum number of performance-based shares that could be issued on outstanding awards if performance is attained at the maximum amount was approximately 585,518 shares. The actual tax benefit realized upon the vesting of restricted shares and performance-based stock is based on the fair value of the shares on the issue date and the estimated tax benefit of the awards is based on fair value of the awards on the grant date. The actual tax benefit realized upon the vesting of restricted shares and performance-based stock in 2018 , 2017 and 2016 was $994,000 , $975,000 and $241,000 , respectively, more than the expected tax benefit for those shares. These differences in actual and expected tax benefits were recorded to tax expense in 2018 and 2017 and directly to shareholders’ equity in 2016 . As of December 31, 2018 , there was $15.4 million of total unrecognized compensation cost related to non-vested share based arrangements under the Plans. That cost is expected to be recognized over a weighted average period of approximately two years. The total fair value of shares vested during the years ended December 31, 2018 , 2017 and 2016 was $8.0 million , $8.9 million and $8.4 million , respectively. The Company issues new shares to satisfy its obligation to issue shares granted pursuant to the Plans. Cash Incentive and Retention Plan The Cash Incentive and Retention Plan (“CIRP”) allows the Company to provide cash compensation to the Company’s and its subsidiaries’ officers and employees. The CIRP is administered by the Compensation Committee of the Board of Directors. The CIRP generally provides for the grants of cash awards, which may be earned pursuant to the achievement of performance criteria established by the Compensation Committee and/or continued employment. The performance criteria, if any, established by the Compensation Committee must relate to one or more of the criteria specified in the CIRP, which includes: earnings, earnings growth, revenues, stock price, return on assets, return on equity, improvement of financial ratings, achievement of balance sheet or income statement objectives and expenses. These criteria may relate to the Company, a particular line of business or a specific subsidiary of the Company. The Company had no expense related to the CIRP in 2018, 2017 and 2016, and no awards were paid in those years. There were no outstanding awards under this plan at December 31, 2018 . Other Employee Benefits Wintrust and its subsidiaries also provide 401(k) Retirement Savings Plans (“401(k) Plans”). The 401(k) Plans cover all employees meeting certain eligibility requirements. Contributions by employees are made through salary deferrals at their direction, subject to certain Plan and statutory limitations. Employer contributions to the 401(k) Plans are made at the employer’s discretion. Generally, participants completing 501 hours of service are eligible to share in an allocation of employer contributions. The Company’s expense for the employer contributions to the 401(k) Plans was approximately $10.4 million in 2018 , $8.9 million in 2017 , and $6.6 million in 2016 . The Wintrust Financial Corporation Employee Stock Purchase Plan (“ESPP”) is designed to encourage greater stock ownership among employees, thereby enhancing employee commitment to the Company. The ESPP gives eligible employees the right to accumulate funds over an offering period to purchase shares of common stock. All shares offered under the ESPP will be either newly issued shares of the Company or shares issued from treasury, if any. In accordance with the ESPP, beginning January 1, 2015, the purchase price of the shares of common stock is equal to 95% of the closing price of the Company’s common stock on the last day of the offering period. During 2018 , 2017 and 2016 , 33,977 , 35,022 and 50,920 , respectively, shares of common stock were purchased by participants and no compensation expense was recorded. The Company plans to continue to offer common stock through this ESPP on an ongoing basis, and in 2018, increased the shares authorized under the ESPP by 200,000 shares. At December 31, 2018 , the Company had an obligation to issue 10,807 shares of common stock to participants and had 216,063 shares available for future grants under the ESPP. As a result of the Company's acquisition of HPK Financial Corporation (“HPK”) in December 2012, the Company assumed the obligations of a noncontributory pension plan, (“the HPK Plan”). The HPK Plan was “frozen” as of December 31, 2006, with no additional years of credit earned for service or compensation paid. As of December 31, 2018 , the projected benefit obligation was $4.9 million and the fair value of the plan's assets was $4.7 million . Similarly, in connection with the Company's acquisition of Diamond in October 2013, the Company assumed the obligation of Diamond's pension plan. The Diamond Plan was “frozen” as of December 31, 2004, and only service and compensation prior to this date is considered in determining benefits. As of December 31, 2018 , the projected benefit obligation was $2.7 million and the fair value of the plan's assets was $1.6 million . The Company has accrued liabilities for the unfunded portions of these plans. The Company recorded (income) expense of $(38,000) , $1.2 million and $526,000 in 2018 , 2017 and 2016 , respectively, related to these plans. The Company does not currently offer other postretirement benefits such as health care or other pension plans. Directors Deferred Fee and Stock Plan The Wintrust Financial Corporation Directors Deferred Fee and Stock Plan (“DDFS Plan”) allows directors of the Company and its subsidiaries to choose to receive payment of directors’ fees in either cash or common stock of the Company and to defer the receipt of the fees. The DDFS Plan is designed to encourage stock ownership by directors. All shares offered under the DDFS Plan will be either newly issued shares of the Company or shares issued from treasury. The number of shares issued is determined on a quarterly basis based on the fees earned during the quarter and the fair market value per share of the common stock on the last trading day of the preceding quarter. The shares are issued annually and the directors are entitled to dividends and voting rights upon the issuance of the shares. During 2018 , 2017 and 2016 , a total of 18,856 shares, 27,508 shares and 25,362 shares, respectively, were issued to directors. For those directors that elect to defer the receipt of the common stock, the Company maintains records of stock units representing an obligation to issue shares of common stock. The number of stock units equals the number of shares that would have been issued had the director not elected to defer receipt of the shares. Additional stock units are credited at the time dividends are paid, however no voting rights are associated with the stock units. The shares of common stock represented by the stock units are issued in the year specified by the directors in their participation agreements. At December 31, 2018 , the Company has an obligation to issue 281,910 shares of common stock to directors and has 74,206 shares available for future grants under the DDFS Plan.

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2018
Regulatory Capital Requirements [Abstract]
Regulatory Matters	Regulatory Matters Banking laws place restrictions upon the amount of dividends that can be paid to Wintrust by the banks. Based on these laws, the banks could, subject to minimum capital requirements, declare dividends to Wintrust without obtaining regulatory approval in an amount not exceeding (a) undivided profits, and (b) the amount of net income reduced by dividends paid for the current and prior two years. During 2018 , 2017 and 2016 , cash dividends totaling $111.0 million , $122.0 million and $59.0 million , respectively, were paid to Wintrust by the banks and other subsidiaries. As of January 1, 2019, the banks had approximately $350.4 million available to be paid as dividends to Wintrust without prior regulatory approval and without reducing their capital below the well-capitalized level. The banks are also required by the Federal Reserve Act to maintain reserves against deposits. Reserves are held either in the form of vault cash or balances maintained with the FRB and are based on the average daily deposit balances and statutory reserve ratios prescribed by the type of deposit account. At December 31, 2018 and 2017 , reserve balances of approximately $611.1 million and $557.7 million , respectively, were required to be maintained at the FRB. The Company and the banks are subject to various regulatory capital requirements established by the federal banking agencies that take into account risk attributable to balance sheet and off-balance sheet activities. Failure to meet minimum capital requirements can initiate certain mandatory — and possibly discretionary — actions by regulators, that if undertaken could have a direct material effect on the Company’s financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Company and the banks must meet specific capital guidelines that involve quantitative measures of the Company’s assets, liabilities, and certain off-balance sheet items as calculated under regulatory accounting practices. Quantitative measures established by regulation to ensure capital adequacy require the Company and the banks to maintain minimum amounts and ratios of total and Tier 1 capital (as defined in the regulations) to risk-weighted assets (as defined) and Tier 1 leverage capital (as defined) to average quarterly assets (as defined). The Federal Reserve’s capital guidelines require bank holding companies to maintain a minimum ratio of qualifying total capital to risk-weighted assets of 8.0% , of which at least 4.50% must be in the form of Common Equity Tier 1 capital and 6.0% must be in the form of Tier 1 capital. The Federal Reserve also requires a minimum leverage ratio of Tier 1 capital to total assets of 4.0% . In addition the Federal Reserve continues to consider the Tier 1 leverage ratio in evaluating proposals for expansion or new activities. As reflected in the following table, the Company met all minimum capital requirements at December 31, 2018 and 2017 : 2018 2017 Total capital to risk weighted assets 11.6 % 12.0 % Tier 1 capital to risk weighted assets 9.7 9.9 Common Equity Tier 1 capital to risk weighted assets 9.3 9.4 Tier 1 leverage Ratio 9.1 9.3 Wintrust is designated as a financial holding company. Bank holding companies approved as financial holding companies may engage in an expanded range of activities, including the businesses conducted by its wealth management subsidiaries. As a financial holding company, Wintrust’s banks are required to maintain their capital positions at the “well-capitalized” level. As of December 31, 2018 , the banks were categorized as well capitalized under the regulatory framework for prompt corrective action. The ratios required for the banks to be “well capitalized” by regulatory definition are 10.0% , 8.0% , 6.5% and 5.0% for total capital to risk-weighted assets, Tier 1 capital to risk-weighted assets, Common Equity Tier 1 capital to risk weighted assets and Tier 1 leverage ratio, respectively. The banks’ actual capital amounts and ratios as of December 31, 2018 and 2017 are presented in the following table: (Dollars in thousands) December 31, 2018 December 31, 2017 Actual To Be Well Capitalized by Regulatory Definition Actual To Be Well Capitalized by Regulatory Definition Amount Ratio Amount Ratio Amount Ratio Amount Ratio Total Capital (to Risk Weighted Assets): Lake Forest Bank $ 424,872 12.5 % $ 338,823 10.0 % $ 366,407 11.6 % $ 317,180 10.0 % Hinsdale Bank 256,166 11.9 220,004 10.0 224,577 11.5 195,125 10.0 Wintrust Bank 613,037 11.5 533,154 10.0 512,581 11.2 456,230 10.0 Libertyville Bank 161,453 11.9 135,262 10.0 141,723 11.4 124,637 10.0 Barrington Bank 258,301 11.1 231,871 10.0 234,930 12.0 195,409 10.0 Crystal Lake Bank 107,041 11.6 92,542 10.0 95,532 11.3 84,664 10.0 Northbrook Bank 236,201 11.1 213,524 10.0 222,441 11.4 194,764 10.0 Schaumburg Bank 113,797 11.4 100,151 10.0 111,772 11.9 93,752 10.0 Village Bank 151,653 11.2 135,695 10.0 145,517 11.9 121,867 10.0 Beverly Bank 146,054 11.8 123,618 10.0 132,516 11.7 112,810 10.0 Town Bank 208,479 11.3 184,825 10.0 188,987 11.4 166,253 10.0 Wheaton Bank 165,798 11.3 147,354 10.0 151,141 11.4 132,211 10.0 State Bank of the Lakes 111,530 11.1 100,654 10.0 105,770 11.4 92,518 10.0 Old Plank Trail Bank 151,889 11.4 132,842 10.0 145,272 11.6 125,642 10.0 St. Charles Bank 115,607 11.4 101,337 10.0 105,778 11.4 92,582 10.0 Tier 1 Capital (to Risk Weighted Assets): Lake Forest Bank $ 402,156 11.9 % $ 271,058 8.0 % $ 347,924 11.0 % $ 253,744 8.0 % Hinsdale Bank 244,036 11.3 176,003 8.0 214,061 11.0 156,100 8.0 Wintrust Bank 545,649 10.2 426,523 8.0 439,061 9.6 364,984 8.0 Libertyville Bank 152,939 11.3 108,209 8.0 134,310 10.8 99,709 8.0 Barrington Bank 252,189 10.9 185,497 8.0 229,311 11.7 156,327 8.0 Crystal Lake Bank 102,404 11.1 74,033 8.0 91,273 10.8 67,731 8.0 Northbrook Bank 223,849 10.5 170,819 8.0 198,628 10.2 155,811 8.0 Schaumburg Bank 108,338 10.8 80,120 8.0 105,733 11.3 75,001 8.0 Village Bank 142,333 10.5 108,556 8.0 136,807 11.2 97,494 8.0 Beverly Bank 141,140 11.4 98,894 8.0 127,561 11.3 90,248 8.0 Town Bank 199,982 10.8 147,860 8.0 180,943 10.9 133,003 8.0 Wheaton Bank 159,718 10.8 117,883 8.0 135,009 10.2 105,769 8.0 State Bank of the Lakes 107,234 10.7 80,523 8.0 95,520 10.3 74,014 8.0 Old Plank Trail Bank 145,779 11.0 106,273 8.0 139,366 11.1 100,514 8.0 St. Charles Bank 111,454 11.0 81,069 8.0 102,251 11.0 74,066 8.0 Common Equity Tier 1 Capital (to Risk Weighted Assets): Lake Forest Bank $ 402,156 11.9 % $ 220,235 6.5 % $ 347,924 11.0 % $ 206,167 6.5 % Hinsdale Bank 244,036 11.3 143,002 6.5 214,061 11.0 126,831 6.5 Wintrust Bank 545,649 10.2 346,550 6.5 439,061 9.6 296,549 6.5 Libertyville Bank 152,939 11.3 87,920 6.5 134,310 10.8 81,014 6.5 Barrington Bank 252,189 10.9 150,716 6.5 229,311 11.7 127,016 6.5 Crystal Lake Bank 102,404 11.1 60,152 6.5 91,273 10.8 55,031 6.5 Northbrook Bank 223,849 10.5 138,791 6.5 198,628 10.2 126,597 6.5 Schaumburg Bank 108,338 10.8 65,098 6.5 105,733 11.3 60,939 6.5 Village Bank 142,333 10.5 88,201 6.5 136,807 11.2 79,214 6.5 Beverly Bank 141,140 11.4 80,352 6.5 127,561 11.3 73,327 6.5 Town Bank 199,982 10.8 120,136 6.5 180,943 10.9 108,065 6.5 Wheaton Bank 159,718 10.8 95,780 6.5 135,009 10.2 85,937 6.5 State Bank of the Lakes 107,234 10.7 65,425 6.5 95,520 10.3 60,137 6.5 Old Plank Trail Bank 145,779 11.0 86,347 6.5 139,366 11.1 81,667 6.5 St. Charles Bank 111,454 11.0 65,869 6.5 102,251 11.0 60,178 6.5 (Dollars in thousands) December 31, 2018 December 31, 2017 Actual To Be Well Capitalized by Regulatory Definition Actual To Be Well Capitalized by Regulatory Definition Amount Ratio Amount Ratio Amount Ratio Amount Ratio Tier 1 Leverage Ratio: Lake Forest Bank $ 402,156 10.7 % $ 187,634 5.0 % $ 347,924 10.3 % $ 168,865 5.0 % Hinsdale Bank 244,036 10.4 117,308 5.0 214,061 10.2 105,086 5.0 Wintrust Bank 545,649 9.7 281,090 5.0 439,061 9.2 237,782 5.0 Libertyville Bank 152,939 10.0 76,247 5.0 134,310 9.8 68,404 5.0 Barrington Bank 252,189 12.9 97,759 5.0 229,311 11.8 97,007 5.0 Crystal Lake Bank 102,404 9.9 51,974 5.0 91,273 9.5 48,069 5.0 Northbrook Bank 223,849 9.8 114,125 5.0 198,628 9.5 104,377 5.0 Schaumburg Bank 108,338 9.5 57,111 5.0 105,733 10.1 52,171 5.0 Village Bank 142,333 9.5 75,197 5.0 136,807 9.7 70,182 5.0 Beverly Bank 141,140 10.7 66,109 5.0 127,561 10.8 59,140 5.0 Town Bank 199,982 10.0 100,257 5.0 180,943 10.1 89,617 5.0 Wheaton Bank 159,718 9.8 81,767 5.0 135,009 9.4 72,152 5.0 State Bank of the Lakes 107,234 9.2 58,068 5.0 95,520 9.2 51,681 5.0 Old Plank Trail Bank 145,779 9.6 76,096 5.0 139,366 9.9 70,735 5.0 St. Charles Bank 111,454 9.8 56,915 5.0 102,251 9.8 51,907 5.0 Wintrust’s mortgage banking division and broker/dealer subsidiary are also required to maintain minimum net worth capital requirements with various governmental agencies. The mortgage banking division’s net worth requirements are governed by the Department of Housing and Urban Development and the broker/dealer’s net worth requirements are governed by the SEC. As of December 31, 2018 , these business units met their minimum net worth capital requirements.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company has outstanding, at any time, a number of commitments to extend credit. These commitments include revolving home equity line and other credit agreements, term loan commitments and standby and commercial letters of credit. Standby and commercial letters of credit are conditional commitments issued to guarantee the performance of a customer to a third party. Standby letters of credit are contingent upon the failure of the customer to perform according to the terms of the underlying contract with the third party, while commercial letters of credit are issued specifically to facilitate commerce and typically result in the commitment being drawn on when the underlying transaction is consummated between the customer and the third party. These commitments involve, to varying degrees, elements of credit and interest rate risk in excess of the amounts recognized in the Consolidated Statements of Condition. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Company uses the same credit policies in making commitments as it does for on-balance sheet instruments. Commitments to extend commercial, commercial real estate and construction loans totaled $4.7 billion and $4.4 billion as of December 31, 2018 and 2017 , respectively, and unused home equity lines totaled $807.9 million and $826.5 million as of December 31, 2018 and 2017 , respectively. Standby and commercial letters of credit totaled $233.3 million at December 31, 2018 and $195.9 million at December 31, 2017 . In addition, at December 31, 2018 and 2017 , the Company had approximately $389.7 million and $446.3 million , respectively, in commitments to fund residential mortgage loans to be sold into the secondary market. These lending commitments are also considered derivative instruments. The Company also enters into forward contracts for the future delivery of residential mortgage loans at specified interest rates to reduce the interest rate risk associated with commitments to fund loans as well as mortgage loans held-for-sale. These forward contracts are also considered derivative instruments and had contractual amounts of approximately $481.6 million at December 31, 2018 and $551.9 million at December 31, 2017 . See Note 21, “Derivative Financial Instruments,” for further discussion on derivative instruments. The Company enters into residential mortgage loan sale agreements with investors in the normal course of business. These agreements usually require certain representations concerning credit information, loan documentation, collateral and insurability. On occasion, investors have requested the Company to indemnify them against losses on certain loans or to repurchase loans which the investors believe do not comply with applicable representations. Management maintains a liability for estimated losses on loans expected to be repurchased or on which indemnification is expected to be provided and regularly evaluates the adequacy of this recourse liability based on trends in repurchase and indemnification requests, actual loss experience, known and inherent risks in the loans, and current economic conditions. The Company sold approximately $4.1 billion of mortgage loans in 2018 and $3.9 billion in 2017 . The liability for estimated losses on repurchase and indemnification claims for residential mortgage loans previously sold to investors was $2.4 million and $3.0 million at December 31, 2018 and 2017 , respectively, and was included in other liabilities on the Consolidated Statements of Condition. Losses charged against the liability were $183,000 in 2018 as compared to $1.4 million in 2017 . These losses relate to mortgages which experienced early payment and other defaults meeting certain representation and warranty recourse requirements. The Company has unfunded commitments to investment partnerships that qualify for CRA purposes totaling $13.6 million as of December 31, 2018 . Of these commitments, $914,000 related to legally-binding unfunded commitments for tax-credit investments and was included within other assets and other liabilities on the consolidated statements of financial condition. The Company utilizes an out-sourced securities clearing platform and has agreed to indemnify the clearing broker of Wintrust Investments for losses that it may sustain from the customer accounts introduced by Wintrust Investments. As of December 31, 2018 , the total amount of customer balances maintained by the clearing broker and subject to indemnification was approximately $11.3 million . Wintrust Investments seeks to control the risks associated with its customers’ activities by requiring customers to maintain margin collateral in compliance with various regulatory and internal guidelines. In accordance with applicable accounting principles, the Company establishes an accrued liability for litigation and threatened litigation actions and proceedings when those actions present loss contingencies which are both probable and estimable. In actions for which a loss is reasonably possible in future periods, the Company determines whether it can estimate a loss or range of possible loss. To determine whether a possible loss is estimable, the Company reviews and evaluates its material litigation on an ongoing basis, in conjunction with any outside counsel handling the matter, in light of potentially relevant factual and legal developments. This review may include information learned through the discovery process, rulings on substantive or dispositive motions, and settlement discussions. On January 15, 2015, Lehman Brothers Holdings, Inc. (“Lehman Holdings”) sent a demand letter asserting that Wintrust Mortgage must indemnify it for losses arising from loans sold by Wintrust Mortgage to Lehman Brothers Bank, FSB under a Loan Purchase Agreement between Wintrust Mortgage, as successor to SGB Corporation, and Lehman Brothers Bank. The demand was the precursor for triggering the alternative dispute resolution process mandated by the U.S. Bankruptcy Court for the Southern District of New York. Lehman Holdings triggered the mandatory alternative dispute resolution process on October 16, 2015. On February 3, 2016, following a ruling by the federal Court of Appeals for the Tenth Circuit that was adverse to Lehman Holdings on the statute of limitations that is applicable to similar loan purchase claims, Lehman Holdings filed a complaint against Wintrust Mortgage and 150 other entities from which it had purchased loans in the U.S. Bankruptcy Court for the Southern District of New York. The mandatory mediation was held on March 16, 2016, but did not result in a consensual resolution of the dispute. The court entered a case management order governing the litigation on November 1, 2016. Lehman Holdings filed an amended complaint against Wintrust Mortgage on December 29, 2016. On March 31, 2017, Wintrust Mortgage moved to dismiss the amended complaint for lack of subject matter jurisdiction and improper venue or to transfer venue. Argument on the motions to dismiss were heard on June 12, 2018. The motion to dismiss for lack of subject matter jurisdiction was denied on August 14, 2018 and the defendants’ motion to transfer venue was denied on October 2, 2018. Wintrust Mortgage has appealed the denial of its motion to dismiss based on improper venue and the denial of its motion to transfer venue. On October 2, 2018, Lehman Holdings asked the court for permission to amend its complaints against Wintrust Mortgage and the other defendants to add loans allegedly purchased from the defendants and sold to various RMBS trusts. The court granted this request and allowed Lehman Holdings to assert the additional claims against existing defendants as a supplemental complaint. Lehman Holdings filed its supplemental complaint against Wintrust Mortgage on December 4, 2018. Wintrust Mortgage’s response to the supplemental complaint is due within 45 days of the court’s approval of a proposed amended scheduling order, which is currently pending. At this time, Lehman Holdings has not provided Wintrust Mortgage with sufficient information to allow Wintrust Mortgage to assess the merits of Lehman Holding’s additional claims or to estimate either the likelihood or amount of any potential liability for the additional claims. The Company has reserved an amount for the Lehman Holdings action that is immaterial to its results of operations or financial condition. Such litigation and threatened litigation actions necessarily involve substantial uncertainty and it is not possible at this time to predict the ultimate resolution or to determine whether, or to what extent, any loss with respect to these legal proceedings may exceed the amounts reserved by the Company. On April 9, 2018, JPMorgan Chase & Co. as successor in interest to Bear Stearns and certain related Bear Stearns entities (collectively, “JPMC”) sent a demand letter to Wintrust Mortgage asserting an indemnification claim of approximately $4.6 million . JPMC alleges that it incurred this loss due to its reliance on misrepresentations in the loans Wintrust Mortgage originated, underwrote and sold to JPMC in the years prior to 2009. JPMC has not provided Wintrust Mortgage with sufficient information concerning the loans allegedly at issue to allow Wintrust Mortgage to assess the merits of JPMC’s allegations or to estimate either the likelihood or amount of any potential liability. On October 17, 2018, a former Wintrust Mortgage employee filed a lawsuit against Wintrust Mortgage alleging violation of California wage payment statutes on behalf of herself and all other hourly, non-exempt employees of Wintrust Mortgage in California from October 17, 2014 through the present. Wintrust Mortgage received service of the complaint on November 4, 2018. Wintrust Mortgage’s response to the complaint was filed on February 25, 2019. At this time, Wintrust Mortgage lacks sufficient information to assess the merits of the allegations or to estimate either the likelihood or amount of any potential liability. On October 17, 2018, two individual plaintiffs filed suit against Northbrook Bank and Tamer Moumen on behalf of themselves and a class of approximately 42 investors in a hedge fund run by defendant Moumen. Plaintiffs allege that defendant Moumen ran a fraudulent Ponzi scheme and ran those funds through deposit accounts at Northbrook Bank. They allege the bank was negligent in failing to close the deposit accounts and that it intentionally aided and abetted defendant Moumen in the alleged fraud. They contend that the bank is liable for losses in excess of $6 million . Northbrook Bank filed its motion to dismiss the complaint on January 15, 2019, which remains pending before the court. Northbrook Bank believes the allegations to be legally and factually meritless and otherwise lacks sufficient information to estimate the amount of any potential liability. In addition, the Company and its subsidiaries, from time to time, are subject to pending and threatened legal action and proceedings arising in the ordinary course of business. Based on information currently available and upon consultation with counsel, management believes that the eventual outcome of any pending or threatened legal actions and proceedings described above, including our ordinary course litigation, will not have a material adverse effect on the operations or financial condition of the Company. However, it is possible that the ultimate resolution of these matters, if unfavorable, may be material to the results of operations or financial condition for a particular period.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The Company primarily enters into derivative financial instruments as part of its strategy to manage its exposure to changes in interest rates. Derivative instruments represent contracts between parties that result in one party delivering cash to the other party based on a notional amount and an underlying term (such as a rate, security price or price index) as specified in the contract. The amount of cash delivered from one party to the other is determined based on the interaction of the notional amount of the contract with the underlying term. Derivatives are also implicit in certain contracts and commitments. The derivative financial instruments currently used by the Company to manage its exposure to interest rate risk include: (1) interest rate swaps to manage the interest rate risk of certain fixed and variable rate assets and variable rate liabilities; (2) interest rate lock commitments provided to customers to fund certain mortgage loans to be sold into the secondary market; (3) forward commitments for the future delivery of such mortgage loans to protect the Company from adverse changes in interest rates and corresponding changes in the value of mortgage loans held-for-sale; and (4) covered call options to economically hedge specific investment securities and receive fee income effectively enhancing the overall yield on such securities to compensate for net interest margin compression. The Company also enters into derivatives (typically interest rate swaps) with certain qualified borrowers to facilitate the borrowers’ risk management strategies and concurrently enters into mirror-image derivatives with a third party counterparty, effectively making a market in the derivatives for such borrowers. Additionally, the Company enters into foreign currency contracts to manage foreign exchange risk associated with certain foreign currency denominated assets. The Company recognizes derivative financial instruments in the consolidated financial statements at fair value regardless of the purpose or intent for holding the instrument. The Company records derivative assets and derivative liabilities on the Consolidated Statements of Condition within accrued interest receivable and other assets and accrued interest payable and other liabilities, respectively. Changes in the fair value of derivative financial instruments are either recognized in income or in shareholders’ equity as a component of other comprehensive income depending on whether the derivative financial instrument qualifies for hedge accounting and, if so, whether it qualifies as a fair value hedge or cash flow hedge. As of January 1, 2018, the Company elected to early adopt ASU No. 2017-12, "Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities." Generally, changes in fair values of derivatives accounted for as fair value hedges are recorded in income in the same period and in the same income statement line as changes in the fair values of the hedged items that relate to the hedged risk(s). Changes in fair values of derivative financial instruments accounted for as cash flow hedges are recorded as a component of other comprehensive income, net of deferred taxes, and reclassified to earnings when the hedged transaction affects earnings. Changes in fair values of derivative financial instruments not designated in a hedging relationship pursuant to ASC 815 are reported in non-interest income during the period of the change. Derivative financial instruments are valued by a third party and are corroborated by comparison with valuations provided by the respective counterparties. Fair values of certain mortgage banking derivatives (interest rate lock commitments and forward commitments to sell mortgage loans) are estimated based on changes in mortgage interest rates from the date of the loan commitment. The fair value of foreign currency derivatives is computed based on changes in foreign currency rates stated in the contract compared to those prevailing at the measurement date. The table below presents the fair value of the Company’s derivative financial instruments as of December 31, 2018 and December 31, 2017 : Derivative Assets Derivative Liabilities Fair Value Fair Value (Dollars in thousands) December 31, 2018 December 31, 2017 December 31, 2018 December 31, 2017 Derivatives designated as hedging instruments under ASC 815: Interest rate derivatives designated as Cash Flow Hedges $ 6,270 $ 11,914 $ 1,656 $ 12 Interest rate derivatives designated as Fair Value Hedges 2,636 2,932 1,756 — Total derivatives designated as hedging instruments under ASC 815 $ 8,906 $ 14,846 $ 3,412 $ 12 Derivatives not designated as hedging instruments under ASC 815: Interest rate derivatives $ 59,519 $ 34,139 $ 59,159 $ 33,704 Interest rate lock commitments 3,405 2,843 2,694 269 Forward commitments to sell mortgage loans — 14 1,486 1,457 Foreign exchange contracts 1,342 227 1,337 229 Total derivatives not designated as hedging instruments under ASC 815 $ 64,266 $ 37,223 $ 64,676 $ 35,659 Total Derivatives $ 73,172 $ 52,069 $ 68,088 $ 35,671 Cash Flow Hedges of Interest Rate Risk The Company’s objectives in using interest rate derivatives are to add stability to net interest income and to manage its exposure to interest rate movements. To accomplish these objectives, the Company primarily uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without the exchange of the underlying notional amount. Interest rate collars designated as cash flow hedges involve the receipt of amounts in which the interest rate specified in the contract exceeds the agreed upon cap strike price or the payment of amounts in which the interest rate specified in the contract is below the agreed upon floor strike price at the end of each period. As of December 31, 2018 , the Company had three interest rate swap derivatives designated as cash flow hedges of variable rate deposits and one interest rate collar derivative designated as a cash flow hedge of variable rate debt. When the relationship between the hedged item and hedging instrument is highly effective at achieving offsetting changes in cash flows attributable to the hedged risk, changes in the fair value of these cash flow hedges are recorded in accumulated other comprehensive income and are subsequently reclassified to interest expense as interest payments are made on such variable rate deposits. The changes in fair value (net of tax) are separately disclosed in the Consolidated Statements of Comprehensive Income. The table below provides details on each of these cash flow hedges as of December 31, 2018 : (Dollars in thousands) December 31, 2018 Maturity Date Notional Amount Fair Value Asset (Liability) Interest Rate Swaps: June 2019 $ 200,000 $ 957 July 2019 250,000 2,196 August 2019 275,000 3,117 Interest Rate Collars: September 2023 144,643 (1,656 ) Total Cash Flow Hedges $ 869,643 $ 4,614 In 2018, the Company terminated five interest rate swap derivatives designated as cash flow hedges of variable rate deposits with a total notional value of $650.0 million . As the hedged forecasted transactions (interest payments on variable rate deposits) will still occur over the remaining term of the terminated derivatives, any prior changes in the fair value of these cash flow hedges will continue to be included within accumulated other comprehensive income and reclassified to interest expense as interest payments continue to be made. In 2018, the Company reclassified approximately $427,000 from accumulated other comprehensive income to interest expense related to these terminated interest rate swap derivatives. A rollforward of the amounts in accumulated other comprehensive gain related to interest rate derivatives designated as cash flow hedges follows: Years Ended December 31, (Dollars in thousands) 2018 2017 Unrealized gain at beginning of period $ 11,902 $ 6,944 Amount reclassified from accumulated other comprehensive income to interest expense on deposits and junior subordinated debentures (7,313 ) (19 ) Amount of gain recognized in other comprehensive income 6,153 4,977 Unrealized gain at end of period $ 10,742 $ 11,902 As of December 31, 2018 , the Company estimates that during the next twelve months, $10.9 million will be reclassified from accumulated other comprehensive loss as a decrease to interest expense. Fair Value Hedges of Interest Rate Risk Interest rate swaps designated as fair value hedges involve the payment of fixed amounts to a counterparty in exchange for the Company receiving variable payments over the life of the agreements without the exchange of the underlying notional amount. As of December 31, 2018 , the Company has fifteen interest rate swaps with an aggregate notional amount of $173.0 million that were designated as fair value hedges primarily associated with fixed rate commercial and industrial and commercial real estate loans as well as life insurance premium finance receivables. Three of these interest rate swaps with an aggregate notional amount of $55.9 million were effective starting after December 31, 2018. For derivatives designated and that qualify as fair value hedges, the net gain or loss from the entire change in the fair value of the derivative instrument is recognized in the same income statement line item as the earnings effect, including the net gain or loss, of the hedged item (interest income earned on fixed rate loans) when the hedged item affects earnings. The following table presents the carrying amount of the hedged assets/(liabilities) and the cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged assets/(liabilities) that are designated as a fair value hedge accounting relationship as of December 31, 2018: December 31, 2018 (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location in the Statement of Condition Carrying Amount of the Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Remaining for any Hedged Assets (Liabilities) for which Hedge Accounting has been Discontinued Interest rate swaps Loans, net of unearned income, excluding covered loans $ 135,944 $ (953 ) $ — Available-for-sale debt securities 1,497 58 — The following table presents the loss or gain recognized related to derivative instruments that are designated as fair value hedges for the respective periods: (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location of Gain or (Loss) Recognized in Income on Derivative Year Ended December 31, 2018 Interest rate swaps Interest and fees on loans $ (131 ) Interest income - investment securities — In 2018, one interest rate swap designated as a fair value hedge accounting relationship was terminated as a result of the full prepayment of the underlying loan (hedged asset). At the time of the termination, the fair value of the interest rate swap asset was approximately $1.4 million with an offsetting cumulative amount of fair value hedging adjustments included in the carrying value of the underlying loan totaling $1.6 million . As the underlying loan was fully paid-off, the remaining cumulative amount of fair value hedging adjustments included in the carrying value of the underlying loan was recorded to interest income. Non-Designated Hedges The Company does not use derivatives for speculative purposes. Derivatives not designated as accounting hedges are used to manage the Company’s economic exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of ASC 815. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings. Interest Rate Derivatives —The Company has interest rate derivatives, including swaps and option products, resulting from a service the Company provides to certain qualified borrowers. The Company’s banking subsidiaries execute certain derivative products (typically interest rate swaps) directly with qualified commercial borrowers to facilitate their respective risk management strategies. For example, these arrangements allow the Company’s commercial borrowers to effectively convert a variable rate loan to a fixed rate. In order to minimize the Company’s exposure on these transactions, the Company simultaneously executes offsetting derivatives with third parties. In most cases, the offsetting derivatives have mirror-image terms, which result in the positions’ changes in fair value substantially offsetting through earnings each period. However, to the extent that the derivatives are not a mirror-image and because of differences in counterparty credit risk, changes in fair value will not completely offset resulting in some earnings impact each period. Changes in the fair value of these derivatives are included in other non-interest income. At December 31, 2018 , the Company had interest rate derivative transactions with an aggregate notional amount of approximately $6.1 billion (all interest rate swaps and caps with customers and third parties) related to this program. These interest rate derivatives had maturity dates ranging from January 2019 to February 2045 . Mortgage Banking Derivatives— These derivatives include interest rate lock commitments provided to customers to fund certain mortgage loans to be sold into the secondary market and forward commitments for the future delivery of such loans. It is the Company’s practice to enter into forward commitments for the future delivery of a portion of our residential mortgage loan production when interest rate lock commitments are entered into in order to economically hedge the effect of future changes in interest rates on its commitments to fund the loans as well as on its portfolio of mortgage loans held-for-sale. The Company’s mortgage banking derivatives have not been designated as being in hedge relationships. At December 31, 2018 , the Company had forward commitments to sell mortgage loans with an aggregate notional amount of approximately $481.6 million and interest rate lock commitments with an aggregate notional amount of approximately $235.8 million . The fair values of these derivatives were estimated based on changes in mortgage rates from the dates of the commitments. Changes in the fair value of these mortgage banking derivatives are included in mortgage banking revenue. Foreign Currency Derivatives— These derivatives include foreign currency contracts used to manage the foreign exchange risk associated with foreign currency denominated assets and transactions. Foreign currency contracts, which include spot and forward contracts, represent agreements to exchange the currency of one country for the currency of another country at an agreed-upon price on an agreed-upon settlement date. As a result of fluctuations in foreign currencies, the U.S. dollar-equivalent value of the foreign currency denominated assets or forecasted transactions increase or decrease. Gains or losses on the derivative instruments related to these foreign currency denominated assets or forecasted transactions are expected to substantially offset this variability. As of December 31, 2018 the Company held foreign currency derivatives with an aggregate notional amount of approximately $40.3 million . Other Derivatives— Periodically, the Company will sell options to a bank or dealer for the right to purchase certain securities held within the banks’ investment portfolios (covered call options). These option transactions are designed primarily to mitigate overall interest rate risk and to increase the total return associated with the investment securities portfolio. These options do not qualify as accounting hedges pursuant to ASC 815, and, accordingly, changes in fair value of these contracts are recognized as other non-interest income. There were no covered call options outstanding as of December 31, 2018 or December 31, 2017 . Amounts included in the Consolidated Statements of Income related to derivative instruments not designated in hedge relationships were as follows: (Dollars in thousands) December 31, Derivative Location in income statement 2018 2017 Interest rate swaps and caps Trading gains (losses), net $ (75 ) $ (848 ) Mortgage banking derivatives Mortgage banking revenue (792 ) 1,314 Covered call options Fees from covered call options 3,519 4,402 Foreign exchange contracts Trading gains (losses), net 20 (38 ) Credit Risk Derivative instruments have inherent risks, primarily market risk and credit risk. Market risk is associated with changes in interest rates and credit risk relates to the risk that the counterparty will fail to perform according to the terms of the agreement. The amounts potentially subject to market and credit risks are the streams of interest payments under the contracts and the market value of the derivative instrument and not the notional principal amounts used to express the volume of the transactions. Market and credit risks are managed and monitored as part of the Company’s overall asset-liability management process, except that the credit risk related to derivatives entered into with certain qualified borrowers is managed through the Company’s standard loan underwriting process since these derivatives are secured through collateral provided by the loan agreements. Actual exposures are monitored against various types of credit limits established to contain risk within parameters. When deemed necessary, appropriate types and amounts of collateral are obtained to minimize credit exposure. The Company has agreements with certain of its interest rate derivative counterparties that contain cross-default provisions, which provide that if the Company defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then the Company could also be declared in default on its derivative obligations. The Company also has agreements with certain of its derivative counterparties that contain a provision allowing the counterparty to terminate the derivative positions if the Company fails to maintain its status as a well or adequately capitalized institution, which would require the Company to settle its obligations under the agreements. As of December 31, 2018 , the fair value of interest rate derivatives in a net liability position that were subject to such agreements, which includes accrued interest related to these agreements, was $5.3 million . If the Company had breached any of these provisions and the derivatives were terminated as a result, the Company would have been required to settle its obligations under the agreements at the termination value and would have been required to pay any additional amounts due in excess of amounts previously posted as collateral with the respective counterparty. The Company is also exposed to the credit risk of its commercial borrowers who are counterparties to interest rate derivatives with the banks. This counterparty risk related to the commercial borrowers is managed and monitored through the banks’ standard underwriting process applicable to loans since these derivatives are secured through collateral provided by the loan agreement. The counterparty risk associated with the mirror-image swaps executed with third parties is monitored and managed in connection with the Company’s overall asset liability management process. The Company records interest rate derivatives subject to master netting agreements at their gross value and does not offset derivative assets and liabilities on the Consolidated Statements of Condition. The tables below summarize the Company's interest rate derivatives and offsetting positions as of the dates shown. Derivative Assets Derivative Liabilities Fair Value Fair Value (Dollars in thousands) December 31, 2018 December 31, 2017 December 31, December 31, Gross Amounts Recognized $ 68,425 $ 48,985 $ 62,571 $ 33,716 Less: Amounts offset in the Statements of Condition — — — — Net amount presented in the Statements of Condition $ 68,425 $ 48,985 $ 62,571 $ 33,716 Gross amounts not offset in the Statements of Condition Offsetting Derivative Positions $ (28,124 ) $ (14,878 ) $ (28,124 ) $ (14,878 ) Collateral Posted (23,810 ) (18,060 ) (2,640 ) (2,220 ) Net Credit Exposure $ 16,491 $ 16,047 $ 31,807 $ 16,618

Fair Value of Assets and Liabil

Fair Value of Assets and Liabilities	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value of Assets and Liabilities	Fair Value of Assets and Liabilities The Company measures, monitors and discloses certain of its assets and liabilities on a fair value basis. These financial assets and financial liabilities are measured at fair value in three levels, based on the markets in which the assets and liabilities are traded and the observability of the inputs used to determine fair value. These levels are: • Level 1 — unadjusted quoted prices in active markets for identical assets or liabilities. • Level 2 — inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability or inputs that are derived principally from or corroborated by observable market data by correlation or other means. • Level 3 — significant unobservable inputs that reflect the Company’s own assumptions that market participants would use in pricing the assets or liabilities. Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation. A financial instrument’s categorization within the above valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the assets or liabilities. Following is a description of the valuation methodologies used for the Company’s assets and liabilities measured at fair value on a recurring basis. Available-for-sale debt securities, trading account securities and equity securities with readily determinable fair value —Fair values for available-for-sale debt securities, trading account securities and equity securities with readily determinable fair value are typically based on prices obtained from independent pricing vendors. Securities measured with these valuation techniques are generally classified as Level 2 of the fair value hierarchy. Typically, standard inputs such as benchmark yields, reported trades for similar securities, issuer spreads, benchmark securities, bids, offers and reference data including market research publications are used to fair value a security. When these inputs are not available, broker/dealer quotes may be obtained by the vendor to determine the fair value of the security. We review the vendor’s pricing methodologies to determine if observable market information is being used, versus unobservable inputs. Fair value measurements using significant inputs that are unobservable in the market due to limited activity or a less liquid market are classified as Level 3 in the fair value hierarchy. The Company’s Investment Operations Department is responsible for the valuation of Level 3 available-for-sale debt securities. The methodology and variables used as inputs in pricing Level 3 securities are derived from a combination of observable and unobservable inputs. The unobservable inputs are determined through internal assumptions that may vary from period to period due to external factors, such as market movement and credit rating adjustments. At December 31, 2018 , the Company classified $108.9 million of municipal securities as Level 3. These municipal securities are bond issues for various municipal government entities primarily located in the Chicago metropolitan area and southern Wisconsin and are privately placed, non-rated bonds without CUSIP numbers. The Company also classified $3.2 million of U.S. government agencies as Level 3 at December 31, 2018 . The Company’s methodology for pricing these securities focuses on three distinct inputs: equivalent rating, yield and other pricing terms. To determine the rating for a given non-rated municipal bond, the Investment Operations Department references a publicly issued bond by the same issuer if available. A reduction is then applied to the rating obtained from the comparable bond, as the Company believes if liquidated, a non-rated bond would be valued less than a similar bond with a verifiable rating. The reduction applied by the Company is one complete rating grade (i.e. a “AA” rating for a comparable bond would be reduced to “A” for the Company’s valuation). In 2018 , all of the ratings derived in the above process by Investment Operations were “BBB” or better, for both bonds with and without comparable bond proxies. The fair value measurement of municipal bonds is sensitive to the rating input, as a higher rating typically results in an increased valuation. The remaining pricing inputs used in the bond valuation are observable. Based on the rating determined in the above process, Investment Operations obtains a corresponding current market yield curve available to market participants. Other terms including coupon, maturity date, redemption price, number of coupon payments per year, and accrual method are obtained from the individual bond term sheets. Certain municipal bonds held by the Company at December 31, 2018 have a call date that has passed, and are now continuously callable. When valuing these bonds, the fair value is capped at par value as the Company assumes a market participant would not pay more than par for a continuously callable bond. To determine the rating for the U.S. government agency securities, the Investment Operations Department assigned a AAA rating as it is guaranteed by the U.S. government. Mortgage loans held-for-sale —The fair value of mortgage loans held-for-sale is determined by reference to investor price sheets for loan products with similar characteristics. Loans held-for-investment —The fair value for loans in which the Company elected the fair value option is estimated by discounting future scheduled cash flows for the specific loan through maturity, adjusted for estimated credit losses and prepayments. The Company uses a discount rate based on the actual coupon rate of the underlying loan. At December 31, 2018 , the Company classified $11.3 million of loans held-for-investment as Level 3. The weighted average discount rate used as an input to value these loans at December 31, 2018 was 4.31% with discount rates applied ranging from 4% - 5% . The higher the rate utilized to discount estimated future cash flows, the lower the fair value measurement. As noted above, the fair value estimate includes assumptions of prepayment speeds and credit losses. The Company included a prepayments speed assumption of 12.06% at December 31, 2018 . Prepayment speeds are inversely related to the fair value of these loans as an increase in prepayment speeds results in a decreased valuation. Additionally, the weighted average credit discount used as an input to value the specific loans was 1.30% with credit discounts ranging from 0% - 7% at December 31, 2018 . MSRs —Fair value for MSRs is determined utilizing a valuation model which calculates the fair value of each servicing rights based on the present value of estimated future cash flows. The Company uses a discount rate commensurate with the risk associated with each servicing rights, given current market conditions. At December 31, 2018 , the Company classified $75.2 million of MSRs as Level 3. The weighted average discount rate used as an input to value the pool of MSRs at December 31, 2018 was 9.98% with discount rates applied ranging from 6% - 18% . The higher the rate utilized to discount estimated future cash flows, the lower the fair value measurement. The fair value of MSRs was also estimated based on other assumptions including prepayment speeds and the cost to service. Prepayment speeds ranged from 6% - 91% or a weighted average prepayment speed of 11.76% . Further, for current and delinquent loans, the Company assumed the average cost of servicing of $77 and $273 , respectively, per loan. Prepayment speeds and the cost to service are both inversely related to the fair value of MSRs as an increase in prepayment speeds or the cost to service results in a decreased valuation. See Note 6, “Mortgage Servicing Rights (“MSRs”),” for further discussion of MSRs. Derivative instruments —The Company’s derivative instruments include interest rate swaps, caps and collars, commitments to fund mortgages for sale into the secondary market (interest rate locks), forward commitments to end investors for the sale of mortgage loans and foreign currency contracts. Interest rate swaps, caps and collars are valued by a third party, using models that primarily use market observable inputs, such as yield curves, and are validated by comparison with valuations provided by the respective counterparties. The credit risk associated with derivative financial instruments that are subject to master netting agreements is measured on a net basis by counterparty portfolio. The fair value for mortgage-related derivatives is based on changes in mortgage rates from the date of the commitments. The fair value of foreign currency derivatives is computed based on change in foreign currency rates stated in the contract compared to those prevailing at the measurement date. At December 31, 2018 , the Company classified $2.5 million of derivative assets related to interest rate locks as Level 3. The fair value of interest rate locks is based on prices obtained for loans with similar characteristics from third parties, adjusted for the pull-through rate, which represents the Company’s best estimate of the likelihood that a committed loan will ultimately fund. The weighted-average pull-through rate at December 31, 2018 was 86.15% with pull-through rates applied ranging from 17% to 100% . Pull-through rates are directly related to the fair value of interest rate locks as an increase in the pull-through rate results in an increased valuation. Nonqualified deferred compensation assets —The underlying assets relating to the nonqualified deferred compensation plan are included in a trust and primarily consist of non-exchange traded institutional funds which are priced based by an independent third party service. The following tables present the balances of assets and liabilities measured at fair value on a recurring basis for the periods presented: December 31, 2018 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 126,404 $ 126,404 $ — $ — U.S. Government agencies 140,307 — 137,157 3,150 Municipal 138,490 — 29,564 108,926 Corporate notes 91,045 — 91,045 — Mortgage-backed 1,629,835 — 1,629,835 — Trading account securities 1,692 — 1,692 — Equity securities with readily determinable fair value 34,717 — 34,717 — Mortgage loans held-for-sale 264,070 — 264,070 — Loans held-for-investment 93,857 — 82,510 11,347 MSRs 75,183 — — 75,183 Nonqualified deferred compensations assets 11,282 — 11,282 — Derivative assets 73,172 — 70,715 2,457 Total $ 2,680,054 $ 126,404 $ 2,352,587 $ 201,063 Derivative liabilities $ 68,088 $ — $ 68,088 $ — December 31, 2017 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 143,822 $ 143,822 $ — $ — U.S. Government agencies 156,915 — 153,136 3,779 Municipal 115,352 — 38,171 77,181 Corporate notes 31,050 — 31,050 — Mortgage-backed 1,319,725 — 1,319,725 — Equity securities 36,802 — 36,802 — Trading account securities 995 — 995 — Mortgage loans held-for-sale 313,592 — 313,592 — Loans held-for-investment 33,717 — — 33,717 MSRs 33,676 — — 33,676 Nonqualified deferred compensations assets 11,065 — 11,065 — Derivative assets 52,069 — 49,912 2,157 Total $ 2,248,780 $ 143,822 $ 1,954,448 $ 150,510 Derivative liabilities $ 35,671 $ — $ 35,671 $ — The aggregate remaining contractual principal balance outstanding as of December 31, 2018 and 2017 for mortgage loans held- for-sale measured at fair value under ASC 825 was $253.7 million and $299.5 million , respectively, while the aggregate fair value of mortgage loans held-for-sale was $264.1 million and $313.6 million , respectively, as shown in the above tables. There were $1.9 million of loans past due greater than 90 days and still accruing interest in the mortgage loans held-for-sale portfolio as of December 31, 2018 and no loans as of December 31, 2017 . The changes in Level 3 assets measured at fair value on a recurring basis during the year ended December 31, 2018 are summarized as follows: U.S. Government Agencies Loans held-for-investment MSRs Derivative assets (Dollars in thousands) Municipal Balance at January 1, 2018 $ 77,181 $ 3,779 $ 33,717 $ 33,676 $ 2,157 Total net gains (losses) included in: Net income (1) — — (1,077 ) 27,701 300 Other comprehensive loss (8,541 ) (314 ) — — — Purchases (2) 63,644 — — 13,806 — Issuances — — — — — Sales — — — — — Settlements (23,358 ) (315 ) (28,367 ) — — Net transfers into/(out of) Level 3 — — 7,074 — — Balance at December 31, 2018 $ 108,926 $ 3,150 $ 11,347 $ 75,183 $ 2,457 (1) Changes in the balance of MSRs and derivative assets as presented in the table above are recorded as a component of mortgage banking revenue in non-interest income. Changes in the balance of loans held-for-investment related to fair value adjustments are recorded as other non-interest income. (2) Purchased as a part of the Veterans First business combination. See Note 7 - Business Combinations and Asset Acquisitions for further discussion. The changes in Level 3 assets measured at fair value on a recurring basis during the year ended December 31, 2017 are summarized as follows: (Dollars in thousands) Municipal U.S. Government Agencies Loans held-for-investment MSRs Derivative assets Balance at January 1, 2017 $ 79,626 $ — $ 22,137 $ 19,103 $ 2,291 Total net gains (losses) included in: Net income (1) — — 1,025 14,573 (134 ) Other comprehensive loss (501 ) (504 ) — — — Purchases 33,593 — — — — Issuances — — — — — Sales — — — — — Settlements (35,537 ) — (13,219 ) — — Net transfers into/(out of) Level 3 (2) — 4,283 23,774 — — Balance at December 31, 2017 $ 77,181 $ 3,779 $ 33,717 $ 33,676 $ 2,157 (1) Changes in the balance of MSRs and derivative assets as presented in the table above are recorded as a component of mortgage banking revenue in non-interest income. Changes in the balance of loans held-for-investment related to fair value adjustments are recorded as other non-interest income. (2) Transfers into Level 3 relate to certain U.S. government agency available-for-sale investment securities and loans reclassified from the held-for-sale portfolio at the time of market conditions or other developments changing management's intent with respect to the disposition of those loans. Also, the Company may be required, from time to time, to measure certain other financial assets at fair value on a nonrecurring basis in accordance with GAAP. These adjustments to fair value usually result from impairment charges on individual assets. For assets measured at fair value on a nonrecurring basis that were still held in the balance sheet at the end of the period, the following table provides the carrying value of the related individual assets or portfolios at December 31, 2018 . December 31, 2018 Year Ended December 31, 2018 Fair Value Losses Recognized, net (Dollars in thousands) Total Level 1 Level 2 Level 3 Impaired loans-collateral based $ 99,803 $ — $ — $ 99,803 $ 18,721 Other real estate owned (1) 24,820 — — 24,820 5,965 Total $ 124,623 $ — $ — $ 124,623 $ 24,686 (1) Fair value losses recognized, net on other real estate owned include valuation adjustments and charge-offs during the respective period. Impaired loans —A loan is considered to be impaired when, based on current information and events, it is probable that the Company will be unable to collect all amounts due pursuant to the contractual terms of the loan agreement. A loan modified in a TDR is an impaired loan according to applicable accounting guidance. Impairment is measured by estimating the fair value of the loan based on the present value of expected cash flows, the market price of the loan, or the fair value of the underlying collateral. Impaired loans are considered a fair value measurement where an allowance is established based on the fair value of collateral. Appraised values, which may require adjustments to market-based valuation inputs, are generally used on real estate collateral-dependent impaired loans. The Company’s Managed Assets Division is primarily responsible for the valuation of Level 3 inputs of impaired loans. For more information on the Managed Assets Division review of impaired loans refer to Note 5 – Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans. At December 31, 2018 , the Company had $127.3 million of impaired loans classified as Level 3. Of the $127.3 million of impaired loans, $99.8 million were measured at fair value based on the underlying collateral of the loan as shown in the table above. The remaining $27.5 million were valued based on discounted cash flows in accordance with ASC 310. Other real estate owned —Other real estate owned is comprised of real estate acquired in partial or full satisfaction of loans and is included in other assets. Other real estate owned is recorded at its estimated fair value less estimated selling costs at the date of transfer, with any excess of the related loan balance over the fair value less expected selling costs charged to the allowance for loan losses. Subsequent changes in value are reported as adjustments to the carrying amount and are recorded in other non-interest expense. Gains and losses upon sale, if any, are also charged to other non-interest expense. Fair value is generally based on third party appraisals and internal estimates that are adjusted by a discount representing the estimated cost of sale and is therefore considered a Level 3 valuation. The Company’s Managed Assets Division is primarily responsible for the valuation of Level 3 inputs for other real estate owned. At December 31, 2018 , the Company had $24.8 million of other real estate owned classified as Level 3. The unobservable input applied to other real estate owned relates to the 10% reduction to the appraisal value representing the estimated cost of sale of the foreclosed property. A higher discount for the estimated cost of sale results in a decreased carrying value. The valuation techniques and significant unobservable inputs used to measure both recurring and non-recurring Level 3 fair value measurements at December 31, 2018 were as follows: (Dollars in thousands) Fair Value Valuation Methodology Significant Unobservable Input Range of Inputs Weighted Average of Inputs Impact to valuation from an increased or higher input value Measured at fair value on a recurring basis: Municipal securities $ 108,926 Bond pricing Equivalent rating BBB-AA+ N/A Increase U.S. Government agencies 3,150 Bond pricing Equivalent rating AAA AAA Increase Loans held-for-investment 11,347 Discounted cash flows Discount rate 4%-5% 4.31% Decrease Credit spread 0%-7% 1.30% Decrease Constant prepayment rate (CPR) 12.06% 12.06% Decrease MSRs 75,183 Discounted cash flows Discount rate 6%-18% 9.98% Decrease Constant prepayment rate (CPR) 6%-91% 11.76% Decrease Cost of servicing $15-$200 $ 77 Decrease Cost of servicing - delinquent $200-$1,000 $ 273 Decrease Derivatives 2,457 Discounted cash flows Pull-through rate 17%-100% 86.15 % Increase Measured at fair value on a non-recurring basis: Impaired loans—collateral based 99,803 Appraisal value Appraisal adjustment - cost of sale 10% 10.00% Decrease Other real estate owned, including covered other real-estate owned 24,820 Appraisal value Appraisal adjustment - cost of sale 10% 10.00% Decrease The Company is required under applicable accounting guidance to report the fair value of all financial instruments on the consolidated statements of condition, including those financial instruments carried at cost. The table below presents the carrying amounts and estimated fair values of the Company’s financial instruments as of the dates shown: December 31, 2018 December 31, 2017 (Dollars in thousands) Carrying Value Fair Value Carrying Value Fair Value Financial Assets: Cash and cash equivalents $ 392,200 $ 392,200 $ 277,591 $ 277,591 Interest bearing deposits with banks 1,099,594 1,099,594 1,063,242 1,063,242 Available-for-sale securities 2,126,081 2,126,081 1,803,666 1,803,666 Held-to-maturity securities 1,067,439 1,036,096 826,449 812,516 Trading account securities 1,692 1,692 995 995 Equity securities with readily determinable fair value 34,717 34,717 — — FHLB and FRB stock, at cost 91,354 91,354 89,989 89,989 Brokerage customer receivables 12,609 12,609 26,431 26,431 Mortgage loans held-for-sale, at fair value 264,070 264,070 313,592 313,592 Loans held-for-investment, at fair value 93,857 93,857 33,717 33,717 Loans held-for-investment, at amortized cost 23,726,834 23,780,739 21,607,080 21,768,978 MSRs 75,183 75,183 33,676 33,676 Nonqualified deferred compensation assets 11,282 11,282 11,065 11,065 Derivative assets 73,172 73,172 52,069 52,069 Accrued interest receivable and other 260,281 260,281 227,649 227,649 Total financial assets $ 29,330,365 $ 29,352,927 $ 26,367,211 $ 26,515,176 Financial Liabilities Non-maturity deposits $ 20,833,837 $ 20,833,837 $ 18,775,977 $ 18,775,977 Deposits with stated maturities 5,260,841 5,283,063 4,407,370 4,350,004 FHLB advances 426,326 429,830 559,663 544,750 Other borrowings 393,855 393,855 266,123 266,123 Subordinated notes 139,210 138,345 139,088 144,266 Junior subordinated debentures 253,566 263,846 253,566 264,696 Derivative liabilities 68,088 68,088 35,671 35,671 Accrued interest payable 16,025 16,025 8,030 8,030 Total financial liabilities $ 27,391,748 $ 27,426,889 $ 24,445,488 $ 24,389,517 Not all the financial instruments listed in the table above are subject to the disclosure provisions of ASC Topic 820, as certain assets and liabilities result in their carrying value approximating fair value. These include cash and cash equivalents, interest bearing deposits with banks, brokerage customer receivables, FHLB and FRB stock, FDIC indemnification liability, accrued interest receivable and accrued interest payable and non-maturity deposits. The following methods and assumptions were used by the Company in estimating fair values of financial instruments that were not previously disclosed. Held-to-maturity securities. Held-to-maturity securities include U.S. Government-sponsored agency securities and municipal bonds issued by various municipal government entities primarily located in the Chicago metropolitan area and southern Wisconsin. Fair values for held-to-maturity securities are typically based on prices obtained from independent pricing vendors. In accordance with ASC 820, the Company has categorized these held-to-maturity securities as a Level 2 fair value measurement. Fair values for certain other held-to-maturity securities are based on the bond pricing methodology discussed previously related to certain available-for-sale securities. In accordance with ASC 820, the Company has categorized these held-to-maturity securities as a Level 3 fair value measurement. Loans held-for-investment, at amortized cost. Fair values are estimated for portfolios of loans with similar financial characteristics. Loans are analyzed by type such as commercial, residential real estate, etc. Each category is further segmented by interest rate type (fixed and variable) and term. For variable-rate loans that reprice frequently, estimated fair values are based on carrying values. The fair value of residential loans is based on secondary market sources for securities backed by similar loans, adjusted for differences in loan characteristics. The fair value for other fixed rate loans is estimated by discounting scheduled cash flows through the estimated maturity using estimated market discount rates that reflect credit and interest rate risks inherent in the loan. In accordance with ASC 820, the Company has categorized loans as a Level 3 fair value measurement. Deposits with stated maturities. The fair value of certificates of deposit is based on the discounted value of contractual cash flows. The discount rate is estimated using the rates currently in effect for deposits of similar remaining maturities. In accordance with ASC 820, the Company has categorized deposits with stated maturities as a Level 3 fair value measurement. FHLB advances. The fair value of FHLB advances is obtained from the FHLB, which uses a discounted cash flow analysis based on current market rates of similar maturity debt securities to discount cash flows. In accordance with ASC 820, the Company has categorized FHLB advances as a Level 3 fair value measurement. Subordinated notes. The fair value of the subordinated notes is based on a market price obtained from an independent pricing vendor. In accordance with ASC 820, the Company has categorized subordinated notes as a Level 2 fair value measurement. Junior subordinated debentures. The fair value of the junior subordinated debentures is based on the discounted value of contractual cash flows. In accordance with ASC 820, the Company has categorized junior subordinated debentures as a Level 3 fair value measurement.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2018
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity A summary of the Company’s common and preferred stock at December 31, 2018 and 2017 is as follows: 2018 2017 Common Stock: Shares authorized 100,000,000 100,000,000 Shares issued 56,518,119 56,068,220 Shares outstanding 56,407,558 55,965,207 Cash dividend per share $ 0.76 $ 0.56 Preferred Stock: Shares authorized 20,000,000 20,000,000 Shares issued 5,000,000 5,000,000 Shares outstanding 5,000,000 5,000,000 The Company reserves shares of its authorized common stock specifically for the 2015 Plan, the ESPP and the DDFS. The reserved shares and these plans are detailed in Note 18 - Stock Compensation Plans and Other Employee Benefit Plans. The Company also reserves its authorized common stock for conversion of common stock warrants. Common Stock Offering In June 2016, the Company issued through a public offering a total of 3,000,000 shares of its common stock. Net proceeds to the Company totaled approximately $152.9 million . Series C Preferred Stock In March 2012, the Company issued and sold 126,500 shares of Series C Preferred Stock for $126.5 million in a public offering. When, as and if declared, dividends on the Series C Preferred Stock were payable quarterly in arrears at a rate of 5.00% per annum. The Series C Preferred Stock was convertible into common stock at the option of the holder subject to customary anti-dilution adjustments. In 2016, pursuant to such terms, 30 shares of the Series C Preferred Stock were converted at the option of the respective holders into 729 shares of the Company's common stock. On April 25, 2017 , 2,073 shares of the Series C Preferred Stock were converted at the option of the respective holder into 51,244 shares of the Company's common stock, pursuant to the terms of the Series C Preferred Stock. On April 27, 2017 , the Company caused a mandatory conversion of its remaining 124,184 shares of Series C Preferred Stock into 3,069,828 shares of the Company's common stock at a conversion rate of 24.72 shares of common stock per share of Series C Preferred Stock. Cash was paid in lieu of fractional shares for an amount considered insignificant. Series D Preferred Stock In June 2015, the Company issued and sold 5,000,000 shares of Series D Preferred Stock for $125.0 million in a public offering. When, as and if declared, dividends on the Series D Preferred Stock are payable quarterly in arrears at a fixed rate of 6.50% per annum from the original issuance date to, but excluding, July 15, 2025 , and from (and including) that date at a floating rate equal to three-month LIBOR plus a spread of 4.06% per annum. Common Stock Warrants Pursuant to the U.S. Department of the Treasury’s (the “U.S. Treasury”) Capital Purchase Program, on December 19, 2008, the Company issued to the U.S. Treasury a warrant to exercise 1,643,295 warrant shares of Wintrust common stock with a term of 10 years. In February 2011, the U.S. Treasury sold all of its interest in the warrant issued to it in a secondary underwritten public offering. During 2017, certain holders of the interest in the warrant exercised 318,491 warrant shares, which resulted in 219,372 shares of common stock issued. During 2018 , certain holders of the interest in the warrant exercised 22,952 warrant shares, which resulted in 16,571 shares of common stock issued. On December 19, 2018, the Company’s warrant shares expired. Any warrant shares not exercised prior to this date expired and became void, and the holder did not receive any shares of the Company’s common stock. Other At the January 2019 Board of Directors meeting, a quarterly cash dividend of $0.25 per share ( $1.00 on an annualized basis) was declared. It was paid on February 21, 2019 to shareholders of record as of February 7, 2019 . The following tables summarize the components of other comprehensive income (loss), including the related income tax effects, for the years ended December 31, 2018 , 2017 and 2016 : (In thousands) Accumulated Unrealized Losses on Securities Accumulated Unrealized Gains (Losses) on Derivative Instruments Accumulated Foreign Currency Translation Adjustments Total Accumulated Other Comprehensive Loss Balance at January 1, 2018 $ (15,813 ) $ 7,164 $ (33,186 ) $ (41,835 ) Cumulative effect adjustment from the adoption of: ASU 2016-01 (1,880 ) — — (1,880 ) ASU 2018-02 (4,517 ) 1,543 — (2,974 ) Other comprehensive (loss) income during the period, net of tax, before reclassification (20,054 ) 4,498 (9,190 ) (24,746 ) Amount reclassified from accumulated other comprehensive income into net income, net of tax (24 ) (5,348 ) — (5,372 ) Amount reclassified from accumulated other comprehensive income related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale (65 ) — — (65 ) Net other comprehensive loss during the period, net of tax $ (20,143 ) $ (850 ) $ (9,190 ) $ (30,183 ) Balance at December 31, 2018 $ (42,353 ) $ 7,857 $ (42,376 ) $ (76,872 ) Balance at January 1, 2017 $ (29,309 ) $ 4,165 $ (40,184 ) $ (65,328 ) Other comprehensive income during the period, net of tax, before reclassification 14,417 3,010 6,998 24,425 Amount reclassified from accumulated other comprehensive income into net income, net of tax (27 ) (11 ) — (38 ) Amount reclassified from accumulated other comprehensive income related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale (894 ) — — (894 ) Net other comprehensive income during the period, net of tax $ 13,496 $ 2,999 $ 6,998 $ 23,493 Balance at December 31, 2017 $ (15,813 ) $ 7,164 $ (33,186 ) $ (41,835 ) Balance at January 1, 2016 $ (17,674 ) $ (2,193 ) $ (42,841 ) $ (62,708 ) Other comprehensive (loss) income during the period, net of tax, before reclassification (17,554 ) 4,464 2,657 (10,433 ) Amount reclassified from accumulated other comprehensive income (loss) into net income, net of tax (4,641 ) 1,894 — (2,747 ) Amount reclassified from accumulated other comprehensive income related to amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale 10,560 — — 10,560 Net other comprehensive (loss) income during the period, net of tax $ (11,635 ) $ 6,358 $ 2,657 $ (2,620 ) Balance at December 31, 2016 $ (29,309 ) $ 4,165 $ (40,184 ) $ (65,328 ) Amount Reclassified from Accumulated Other Comprehensive Income for the Year Ended, Details Regarding the Component of Accumulated Other Comprehensive Income December 31, Impacted Line on the Consolidated Statements of Income 2018 2017 Accumulated unrealized losses on available-for-sale securities Gains included in net income $ 33 $ 45 Gains on investment securities, net 33 45 Income before taxes Tax effect (9 ) (18 ) Income tax expense Net of tax $ 24 $ 27 Net income Accumulated unrealized losses on derivative instruments Amount reclassified to interest expense on deposits $ (7,549 ) $ (1,085 ) Interest on deposits Amount reclassified to interest expense on other borrowings 236 — Interest on other borrowings Amount reclassified to interest expense on junior subordinated debentures — 1,066 Interest on junior subordinated debentures 7,313 19 Income before taxes Tax effect (1,965 ) (8 ) Income tax expense Net of tax $ 5,348 $ 11 Net income

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment Information	Segment Information The Company’s operations consist of three primary segments: community banking, specialty finance and wealth management. The three reportable segments are strategic business units that are separately managed as they offer different products and services and have different marketing strategies. In addition, each segment’s customer base has varying characteristics and each segment has a different regulatory environment. While the Company’s management monitors each of the fifteen bank subsidiaries’ operations and profitability separately, these subsidiaries have been aggregated into one reportable operating segment due to the similarities in products and services, customer base, operations, profitability measures and economic characteristics. For purposes of internal segment profitability, management allocates certain intersegment and parent company balances. Management allocates a portion of revenues to the specialty finance segment related to loans and leases originated by the specialty finance segment and sold or assigned to the community banking segment. Similarly, for purposes of analyzing the contribution from the wealth management segment, management allocates a portion of the net interest income earned by the community banking segment on deposit balances of customers of the wealth management segment to the wealth management segment. See Note 10, “Deposits,” for more information on these deposits. Finally, expenses incurred at the Wintrust parent company are allocated to each segment based on each segment's risk-weighted assets. The segment financial information provided in the following tables has been derived from the internal profitability reporting system used by management to monitor and manage the financial performance of the Company. The accounting policies of the segments are substantially similar to those described in the Summary of Significant Accounting Policies in Note 1. The Company evaluates segment performance based on after-tax profit or loss and other appropriate profitability measures common to each segment. The following is a summary of certain operating information for reportable segments: (Dollars in thousands) Community Banking Specialty Finance Wealth Management Total Operating Segments Intersegment Eliminations Consolidated 2018 Net interest income $ 791,838 $ 136,981 $ 17,455 $ 946,274 $ 18,629 $ 964,903 Provision for credit losses 28,586 6,246 — 34,832 — 34,832 Non-interest income 238,668 65,898 91,896 396,462 (40,312 ) 356,150 Non-interest expense 681,749 84,248 81,774 847,771 (21,683 ) 826,088 Income tax expense 79,361 30,325 7,281 116,967 — 116,967 Net income $ 240,810 $ 82,060 $ 20,296 $ 343,166 $ — $ 343,166 Total assets at end of year $ 25,438,454 $ 5,073,011 $ 733,384 $ 31,244,849 $ — $ 31,244,849 2017 Net interest income $ 677,481 $ 118,320 $ 18,919 $ 814,720 $ 17,356 $ 832,076 Provision for credit losses 27,059 2,709 — 29,768 — 29,768 Non-interest income 211,354 60,405 84,312 356,071 (36,565 ) 319,506 Non-interest expense 599,455 74,559 77,012 751,026 (19,209 ) 731,817 Income tax expense 87,486 35,775 9,054 132,315 — 132,315 Net income $ 174,835 $ 65,682 $ 17,165 $ 257,682 $ — $ 257,682 Total assets at end of year $ 22,781,923 $ 4,515,766 $ 618,281 $ 27,915,970 $ — $ 27,915,970 2016 Net interest income $ 588,847 $ 98,248 $ 18,611 $ 705,706 $ 16,487 $ 722,193 Provision for credit losses 30,862 3,222 — 34,084 — 34,084 Non-interest income 230,414 49,706 78,478 358,598 (33,168 ) 325,430 Non-interest expense 556,798 66,460 75,108 698,366 (16,681 ) 681,685 Income tax expense 86,933 29,512 8,534 124,979 — 124,979 Net income $ 144,668 $ 48,760 $ 13,447 $ 206,875 $ — $ 206,875 Total assets at end of year $ 21,172,080 $ 3,884,373 $ 612,100 $ 25,668,553 $ — $ 25,668,553

Condensed Parent Company Financ

Condensed Parent Company Financial Statements	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Condensed Parent Company Financial Statements	Condensed Parent Company Financial Statements Condensed parent company only financial statements of Wintrust follow: Statements of Financial Condition December 31, (In thousands) 2018 2017 Assets Cash $ 37,931 $ 78,045 Available-for-sale debt securities and equity securities with readily determinable fair value 12,765 14,461 Investment in and receivable from subsidiaries 3,660,968 3,249,202 Loans, net of unearned income 1,200 1,845 Allowance for loan losses — — Net loans $ 1,200 $ 1,845 Goodwill 8,371 8,371 Other assets 206,902 174,781 Total assets $ 3,928,137 $ 3,526,705 Liabilities and Shareholders’ Equity Other liabilities $ 75,609 $ 66,909 Subordinated notes 139,210 139,088 Other borrowings 192,182 90,203 Junior subordinated debentures 253,566 253,566 Shareholders’ equity 3,267,570 2,976,939 Total liabilities and shareholders’ equity $ 3,928,137 $ 3,526,705 Statements of Income Years Ended December 31, (In thousands) 2018 2017 2016 Income Dividends and other revenue from subsidiaries $ 171,388 $ 155,969 $ 89,184 Other income 4 2,488 4,344 Total income $ 171,392 $ 158,457 $ 93,528 Expenses Interest expense $ 22,375 $ 19,207 $ 18,498 Salaries and employee benefits 64,726 50,683 34,299 Other expenses 108,038 74,618 62,778 Total expenses $ 195,139 $ 144,508 $ 115,575 (Loss) income before income taxes and equity in undistributed income of subsidiaries $ (23,747 ) $ 13,949 $ (22,047 ) Income tax benefit 34,186 47,139 31,061 Income before equity in undistributed net income of subsidiaries $ 10,439 $ 61,088 $ 9,014 Equity in undistributed net income of subsidiaries 332,727 196,594 197,861 Net income $ 343,166 $ 257,682 $ 206,875 Statements of Cash Flows Years Ended December 31, (In thousands) 2018 2017 2016 Operating Activities: Net income $ 343,166 $ 257,682 $ 206,875 Adjustments to reconcile net income to net cash provided by (used for) operating activities Provision for credit losses 56 — — Gain on early extinguishment of debt — — (4,305 ) Depreciation and amortization 11,943 10,783 10,400 Deferred income tax expense (benefit) 502 2,809 (601 ) Stock-based compensation expense 6,025 5,185 3,762 Decrease (increase) in other assets 3,685 1,956 (319 ) Increase in other liabilities 650 9,967 9,618 Equity in undistributed net income of subsidiaries (332,727 ) (196,594 ) (197,861 ) Net Cash Provided by Operating Activities $ 33,300 $ 91,788 $ 27,569 Investing Activities: Capital distributions from (contributions to) subsidiaries, net $ 4,632 $ (42,736 ) $ (118,575 ) Net cash paid for acquisitions, net (87,081 ) — (61,308 ) Other investing activity, net (57,143 ) (28,132 ) (18,051 ) Net Cash Used for Investing Activities $ (139,592 ) $ (70,868 ) $ (197,934 ) Financing Activities: Increase (decrease) in subordinated notes, other borrowings and junior subordinated debentures, net $ 101,910 $ 20,008 $ (26,251 ) Proceeds from the issuance of common stock, net — — 152,911 Issuance of common shares resulting from exercise of stock options, employee stock purchase plan and conversion of common stock warrants 15,903 28,229 15,828 Dividends paid (50,987 ) (40,543 ) (38,568 ) Common stock repurchases for tax withholdings related to stock-based compensation (648 ) (397 ) (616 ) Net Cash Provided by Financing Activities $ 66,178 $ 7,297 $ 103,304 Net (Decrease) Increase in Cash and Cash Equivalents $ (40,114 ) $ 28,217 $ (67,061 ) Cash and Cash Equivalents at Beginning of Year 78,045 49,828 116,889 Cash and Cash Equivalents at End of Year $ 37,931 $ 78,045 $ 49,828

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table sets forth the computation of basic and diluted earnings per common share for 2018 , 2017 and 2016 : (In thousands, except per share data) 2018 2017 2016 Net income $ 343,166 $ 257,682 $ 206,875 Less: Preferred stock dividends 8,200 9,778 14,513 Net income applicable to common shares—Basic (A) $ 334,966 $ 247,904 $ 192,362 Add: Dividends on convertible preferred stock, if dilutive — 1,578 6,313 Net income applicable to common shares—Diluted (B) $ 334,966 $ 249,482 $ 198,675 Weighted average common shares outstanding (C) 56,300 54,703 50,278 Effect of dilutive potential common shares: Common stock equivalents 908 998 894 Convertible preferred stock, if dilutive — 985 3,100 Total dilutive potential common shares 908 1,983 3,994 Weighted average common shares and effect of dilutive potential common shares (D) 57,208 56,686 54,272 Net income per common share: Basic (A/C) $ 5.95 $ 4.53 $ 3.83 Diluted (B/D) 5.86 4.40 3.66 Potentially dilutive common shares can result from stock options, restricted stock unit awards, stock warrants, the Company’s convertible preferred stock and shares to be issued under the ESPP and the DDFS Plan, being treated as if they had been either exercised or issued, computed by application of the treasury stock method. While potentially dilutive common shares are typically included in the computation of diluted earnings per share, potentially dilutive common shares are excluded from this computation in periods in which the effect would reduce the loss per share or increase the income per share. For diluted earnings per share, net income applicable to common shares can be affected by the conversion of the Company’s convertible preferred stock. Where the effect of this conversion would reduce the loss per share or increase the income per share, net income applicable to common shares is not adjusted by the associated preferred dividends.

Quarterly Financial Summary (Un

Quarterly Financial Summary (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Summary (Unaudited)	Quarterly Financial Summary (Unaudited) The following is a summary of quarterly financial information for the years ended December 31, 2018 and 2017 : 2018 Quarters 2017 Quarters (In thousands, except per share data) First Second Third Fourth First Second Third Fourth Interest income $ 261,205 284,047 304,962 320,596 $ 215,759 231,181 247,688 251,840 Interest expense 36,123 45,877 57,399 66,508 23,179 26,772 31,700 32,741 Net interest income 225,082 238,170 247,563 254,088 192,580 204,409 215,988 219,099 Provision for credit losses 8,346 5,043 11,042 10,401 5,209 8,891 7,896 7,772 Net interest income after provision for credit losses 216,736 233,127 236,521 243,687 187,371 195,518 208,092 211,327 Non-interest income, excluding net securities gains (losses) 86,030 95,221 99,840 77,957 68,820 89,925 79,692 81,024 (Losses) gains on investment securities, net (351 ) 12 90 (2,649 ) (55 ) 47 39 14 Non-interest expense 194,349 206,769 213,637 211,333 168,118 183,544 183,575 196,580 Income before taxes 108,066 121,591 122,814 107,662 88,018 101,946 104,248 95,785 Income tax expense 26,085 32,011 30,866 28,005 29,640 37,049 38,622 27,004 Net income $ 81,981 89,580 91,948 79,657 $ 58,378 64,897 65,626 68,781 Preferred stock dividends 2,050 2,050 2,050 2,050 3,628 2,050 2,050 2,050 Net income applicable to common shares $ 79,931 87,530 89,898 77,607 $ 54,750 62,847 63,576 66,731 Net income per common share: Basic $ 1.42 $ 1.55 $ 1.59 $ 1.38 $ 1.05 $ 1.15 $ 1.14 $ 1.19 Diluted 1.40 1.53 1.57 1.35 1.00 1.11 1.12 1.17 Cash dividends declared per common share 0.19 0.19 0.19 0.19 0.14 0.14 0.14 0.14

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On February 20, 2019, the Company announced the signing of a definitive agreement to acquire Rush-Oak Corporation (“ROC”). ROC is the parent company of Oak Bank, which operates a banking location in the Gold Coast neighborhood of Chicago, Illinois. As of December 31, 2018, Oak Bank had approximately $196 million in assets, approximately $143 million in loans and approximately $158 million in deposits. On February 15, 2019, the Receivables Purchase Agreement with an unrelated third party was amended to extend the maturity date from December 16, 2019 to December 15, 2020. Additionally, at that time, the unrelated third party paid an additional C$20 million under the Receivables Purchase Agreement, which increased the total payments to C$210 million . For additional discussion of the Receivables Purchase Agreement, see Note 13 - Other Borrowings.

Summary Of Significant Accoun_2

Summary Of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Basis of Accounting	The accounting and reporting policies of Wintrust Financial Corporation (“Wintrust” or the “Company”) and its subsidiaries conform to generally accepted accounting principles in the United States and prevailing practices of the banking industry. In the preparation of the consolidated financial statements, management is required to make certain estimates and assumptions that affect the reported amounts contained in the consolidated financial statements. Management believes that the estimates made are reasonable; however, changes in estimates may be required if economic or other conditions change beyond management’s expectations. Reclassifications of certain prior year amounts have been made to conform to the current year presentation. The following is a summary of the Company’s significant accounting policies.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements of Wintrust include the accounts of the Company and its subsidiaries. All significant intercompany accounts and transactions have been eliminated in the consolidated financial statements.
Earnings per Share	Earnings per Share Basic earnings per share is computed by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted earnings per share reflects the potential dilution that would occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company. The weighted-average number of common shares outstanding is increased by the assumed conversion of outstanding convertible preferred stock shares from the beginning of the year or date of issuance, if later, and the number of common shares that would be issued assuming the exercise of stock options, the issuance of restricted shares and stock warrants using the treasury stock method. The adjustments to the weighted-average common shares outstanding are only made when such adjustments will dilute earnings per common share. Net income applicable to common shares used in the diluted earnings per share calculation can be affected by the conversion of the Company's preferred stock. Where the effect of this conversion would reduce the loss per share or increase the income per share, net income applicable to common shares is not adjusted by the associated preferred dividends. Potentially dilutive common shares can result from stock options, restricted stock unit awards, stock warrants, the Company’s convertible preferred stock and shares to be issued under the ESPP and the DDFS Plan, being treated as if they had been either exercised or issued, computed by application of the treasury stock method. While potentially dilutive common shares are typically included in the computation of diluted earnings per share, potentially dilutive common shares are excluded from this computation in periods in which the effect would reduce the loss per share or increase the income per share. For diluted earnings per share, net income applicable to common shares can be affected by the conversion of the Company’s convertible preferred stock. Where the effect of this conversion would reduce the loss per share or increase the income per share, net income applicable to common shares is not adjusted by the associated preferred dividends.
Business Combinations	Business Combinations The Company accounts for business combinations under the acquisition method of accounting in accordance with ASC 805, “Business Combinations” (“ASC 805”) when it obtains control of a business. When determining whether a business has been acquired, the Company first evaluates whether substantially all of the fair value of the gross assets acquired are concentrated in a single identifiable asset or a group of similar identifiable assets. If concentrated in such a manner, the set of assets and activities is not a business. If not concentrated in such a manner, the Company assesses whether the set meets the definition of a business by containing inputs, outputs and at least one substantive process. If the set represents a business, the Company recognizes the fair value of the assets acquired and liabilities assumed, immediately expenses transaction costs and accounts for restructuring plans separately from the business combination. There is no separate recognition of the acquired allowance for loan losses on the acquirer’s balance sheet as credit related factors are incorporated directly into the fair value of the loans recorded at the acquisition date. The excess of the cost of the acquisition over the fair value of the net tangible and intangible assets acquired is recorded as goodwill. Alternatively, a gain is recorded equal to the amount by which the fair value of assets purchased exceeds the fair value of liabilities assumed and consideration paid. If the set of assets and activities do not constitute a business, the transaction is accounted for as an asset acquisition. The cost of a group of assets acquired is allocated to the individual assets acquired or liabilities assumed based on the relative fair value and does not result in the recognition of goodwill. Generally, any excess of the cost of the transaction over the fair value of the individual assets acquired or liabilities assumed, or, in contrast, any excess of the fair value of the individual assets acquired or liabilities assumed over the cost of the transaction, should be allocated on a relative fair value basis. Certain "non-qualifying" assets are excluded from this allocation, and are recognized at the individual asset's fair value. Results of operations of the acquired business are included in the income statement from the effective date of acquisition. Subsequent adjustments to provisional amounts that are identified in reporting periods after the acquisition date of the business combination and asset acquisitions are recognized in the reporting period in which the adjustment amounts are determined. From 2010 to 2012, the Company acquired the banking operations, including the acquisition of certain assets and the assumption of liabilities, of nine financial institutions in FDIC-assisted transactions. Loans comprised the majority of the assets acquired in nearly all of these FDIC-assisted transactions, of which eight such transactions were subject to loss sharing agreements with the FDIC whereby the FDIC agreed to reimburse the Company for 80% of losses incurred on the purchased loans, other real estate owned (“OREO”), and certain other assets. Additionally, clawback provisions within these loss share agreements with the FDIC required the Company to reimburse the FDIC in the event that actual losses on covered assets were lower than the original loss estimates agreed upon with the FDIC with respect of such assets in the loss share agreements. The Company refers to the loans subject to these loss sharing agreements as “covered loans” and uses the term “covered assets” to refer to covered loans, covered OREO and certain other covered assets during periods subject to such agreements. As of dates subject to such agreements, the loans covered by the loss share agreements were classified and presented as covered loans and the estimated reimbursable losses were recorded as an FDIC indemnification asset or liability in the Consolidated Statements of Condition. The Company recorded the acquired assets and liabilities at their estimated fair values at the acquisition date. The fair value for loans reflected expected credit losses at the acquisition date. Therefore, the Company only recognized a provision for credit losses and charge-offs on the acquired loans for any further credit deterioration subsequent to the acquisition date. See Note 5, “Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans,” for further discussion of the allowance on covered loans. The loss share agreements with the FDIC covered realized losses on loans, foreclosed real estate and certain other assets and required the Company to record loss share assets and liabilities that were measured separately from the loan portfolios because they were not contractually embedded in the loans and were not transferable with the loans should the Company have chosen to dispose of them. Fair values at the acquisition dates were estimated based on projected cash flows available for loss share based on the credit adjustments estimated for each loan pool and the loss share percentages. The loss share assets and liabilities were recorded as FDIC indemnification assets and other liabilities, respectively, on the Consolidated Statements of Condition as of dates covered by loss share agreements. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses reduced the FDIC indemnification assets. Reductions to expected losses, to the extent such reductions to expected losses were the result of an improvement to the actual or expected cash flows from the covered assets, also reduced the FDIC indemnification assets and, if necessary, increased any loss share liability when necessary reductions exceeded the current value of the FDIC indemnification assets. In accordance with the clawback provision noted above, the Company was required to reimburse the FDIC when actual losses were less than certain thresholds established for each loss share agreement. The balance of these estimated reimbursements in accordance with clawback provisions and any related amortization were adjusted periodically for changes in the expected losses on covered assets. On the Consolidated Statements of Condition as of dates subject to loss share agreements, estimated reimbursements from clawback provisions were recorded as a reduction to the FDIC indemnification asset or, if necessary, an increase to the loss share liability, which was included within accrued interest payable and other liabilities. In the second quarter of 2017, the Company recorded a $4.9 million reduction to the estimated loss share liability as a result of an adjustment related to such clawback provisions. Although these assets were contractual receivables from the FDIC and these liabilities were contractual payables to the FDIC, there were no contractual interest rates. Additional expected losses, to the extent such expected losses resulted in recognition of an allowance for covered loan losses, increased the FDIC indemnification asset or reduced the FDIC indemnification liability. The corresponding amortization was recorded as a component of non-interest income on the Consolidated Statements of Income during periods covered by the loss share agreements.
Cash Equivalents	Cash Equivalents For purposes of the consolidated statements of cash flows, Wintrust considers cash on hand, cash items in the process of collection, non-interest bearing amounts due from correspondent banks, federal funds sold and securities purchased under resale agreements with original maturities of three months or less, to be cash equivalents.
Investment Securities	Investment Securities The Company classifies debt and equity securities upon purchase in one of five categories: trading, held-to-maturity debt securities, available-for-sale debt securities, equity securities with a readily determinable fair value or equity securities without a readily determinable fair value. Debt and equity securities held for resale are classified as trading securities. Debt securities for which the Company has the ability and positive intent to hold until maturity are classified as held-to-maturity. All other debt securities are classified as available-for-sale as they may be sold prior to maturity in response to changes in the Company’s interest rate risk profile, funding needs, demand for collateralized deposits by public entities or other reasons. Equity securities are classified based upon whether a readily determinable fair value exists on such security. The fair value of an equity security is readily determinable if it meets certain conditions, including whether sales prices or bid-ask quotes are currently available on certain securities exchanges; traded only in a foreign market that is of a breadth and scope comparable to one of the U.S. markets; or the security is an investment in a mutual fund or similar structure with a fair value per share or unit that is determined and published, and is the basis for current transactions. Held-to-maturity debt securities are stated at amortized cost, which represents actual cost adjusted for premium amortization and discount accretion using methods that approximate the effective interest method. Available-for-sale debt securities are stated at fair value, with unrealized gains and losses, net of related taxes, included in shareholders’ equity as a separate component of other comprehensive income. Trading account securities and equity securities with a readily determinable fair value are stated at fair value. Realized and unrealized gains and losses from sales and fair value adjustments are included in other non-interest income. Equity securities without a readily determinable fair value are stated at either a calculated net asset value per share, if available, or the cost of the security minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar instrument of the same issuer. Subsequent to classification at the time of purchase, the Company may transfer debt securities between trading, held-to-maturity, or available-for-sale. For debt securities transferred to trading, the current unrealized gain or loss at the date of transfer, net of related taxes, is immediately recognized in earnings. Debt securities transferred from trading to either held-to-maturity or available-for-sale has already recognized any unrealized gain or loss into earnings and this amount is not reversed. Unrealized gains or losses, net related taxes, for available-for-sale debt securities transferred to held-to-maturity remains as a separate component of other comprehensive income and an offsetting discount included in the amortized cost of the held-to-maturity debt security. These amounts are amortized over the remaining life of the debt security in equal and offsetting amounts. Unrealized gains or losses for held-to-maturity debt securities transferred to available-for-sale are recognized at the transfer date as a separate component of other comprehensive income, net of related taxes. Declines in the fair value of held-to-maturity and available-for-sale debt investment securities (with certain exceptions for debt securities noted below) that are deemed to be other-than-temporary are charged to earnings as a realized loss, and a new cost basis for the securities is established. In evaluating other-than-temporary impairment, management considers the length of time and extent to which the fair value has been less than cost, the financial condition and near-term prospects of the issuer, and the intent and ability of the Company to retain its investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value in the near term. Declines in the fair value of debt securities below amortized cost are deemed to be other-than-temporary in circumstances where: (1) the Company has the intent to sell a security; (2) it is more likely than not that the Company will be required to sell the debt security before recovery of its amortized cost basis; or (3) the Company does not expect to recover the entire amortized cost basis of the debt security. If the Company intends to sell a debt security or if it is more likely than not that the Company will be required to sell the debt security before recovery, an other-than-temporary impairment write-down is recognized in earnings equal to the difference between the debt security’s amortized cost basis and its fair value. If an entity does not intend to sell the debt security or it is not more likely than not that it will be required to sell the debt security before recovery, the other-than-temporary impairment write-down is separated into an amount representing credit loss, which is recognized in earnings, and an amount related to all other factors, which is recognized in other comprehensive income. Interest and dividends, including amortization of premiums and accretion of discounts, are recognized as interest income when earned. Realized gains and losses on sales (using the specific identification method), unrealized gains and losses on equity securities and declines in value judged to be other-than-temporary are included in non-interest income. The Company conducts a regular assessment of its investment securities to determine whether securities are other-than-temporarily impaired considering, among other factors, the nature of the securities, credit ratings or financial condition of the issuer, the extent and duration of the unrealized loss, expected cash flows, market conditions and the Company’s ability to hold the securities through the anticipated recovery period.
FHLB and FRB Stock	FHLB and FRB Stock Investments in FHLB and FRB stock are restricted as to redemption and are carried at cost.
Securities Purchased Under Resale Agreements and Securities Sold Under Repurchase Agreements	Securities Purchased Under Resale Agreements and Securities Sold Under Repurchase Agreements Securities purchased under resale agreements and securities sold under repurchase agreements are generally treated as collateralized financing transactions and are recorded at the amount at which the securities were acquired or sold plus accrued interest. Securities, consisting of U.S. Treasury, U.S. Government agency and mortgage-backed securities, pledged as collateral under these financing arrangements cannot be sold by the secured party. The fair value of collateral either received from or provided to a third party is monitored and additional collateral is obtained or requested to be returned as deemed appropriate.
Brokerage Customer Receivables	Brokerage Customer Receivables The Company, under an agreement with an out-sourced securities clearing firm, extends credit to its brokerage customers to finance their purchases of securities on margin. The Company receives income from interest charged on such extensions of credit. Brokerage customer receivables represent amounts due on margin balances. Securities owned by customers are held as collateral for these receivables.
Mortgage Loans Held-for-Sale	Mortgage Loans Held-for-Sale Mortgage loans are classified as held-for-sale when originated or acquired with the intent to sell the loan into the secondary market. ASC 825, “Financial Instruments” provides entities with an option to report selected financial assets and liabilities at fair value. Mortgage loans classified as held-for-sale are measured at fair value which is determined by reference to investor prices for loan products with similar characteristics. Changes in fair value are recognized in mortgage banking revenue. Market conditions or other developments may change management’s intent with respect to the disposition of these loans and loans previously classified as mortgage loans held-for-sale may be reclassified to the loans held-for-investment portfolio, with the balance transferred continuing to be carried at fair value.
Loans and Leases, Allowance for Loan Losses, Allowance for Covered Loan Losses and Allowance for Losses on Lending-Related Commitments	Loans and Leases, Allowance for Loan Losses, Allowance for Covered Loan Losses and Allowance for Losses on Lending-Related Commitments Loans are generally reported at the principal amount outstanding, net of unearned income. Interest income is recognized when earned. Loan origination fees and certain direct origination costs are deferred and amortized over the expected life of the loan as an adjustment to the yield using methods that approximate the effective interest method. Finance charges on premium finance receivables are earned over the term of the loan, using a method which approximates the effective yield method. Leases classified as capital leases are included within lease loans for financial statement purposes. Capital leases are stated as the sum of remaining minimum lease payments from lessees plus estimated residual values less unearned lease income. Unearned lease income on capital leases is recognized over the term of the leases using the effective interest method. Interest income is not accrued on loans where management has determined that the borrowers may be unable to meet contractual principal and/or interest obligations, or where interest or principal is 90 days or more past due, unless the loans are adequately secured and in the process of collection. Cash receipts on non-accrual loans are generally applied to the principal balance until the remaining balance is considered collectible, at which time interest income may be recognized when received. The Company maintains its allowance for loan losses at a level believed appropriate by management to absorb probable losses inherent in the loan portfolio and is based on the size and current risk characteristics of the loan portfolio. Determination of the allowance is inherently subjective as it requires significant estimates, including the amounts and timing of expected future cash flows on impaired loans, estimated losses on pools of homogeneous loans based on the average historical loss experience, and qualitative considerations. The allowance for loan losses includes the following components: 1) specific reserves on impaired loans, 2) a general reserve based upon historical loss experience and 3) qualitative factors to adjust the historical loss experience used, if deemed necessary. If a loan is impaired, the Company analyzes the loan for purposes of calculating our specific impairment reserves. Loans with a credit risk rating of a 6 through 9 are reviewed to determine if (a) an amount is deemed uncollectible (a charge-off) or (b) it is probable that the Company will be unable to collect amounts due in accordance with the original contractual terms of the loan (an impaired loan). If a loan is impaired, the carrying amount of the loan is compared to the expected payments to be received, discounted at the loan’s original rate, or for collateral dependent loans, to the fair value of the collateral less the estimated cost to sell. Any shortfall is recorded as a specific reserve. For loans that are not considered impaired loans, a general reserve is established based on historical loss experience, adjusted for certain qualitative factors, related to the type of loan collateral, if any, and the assigned credit risk rating. Such qualitative factors assessed by management include the following: • an assessment of internally-evaluated problem loans and historical loss experience; • changes in the composition of the loan portfolio, changes in historical loss experience; • changes in lending policies and procedures, including underwriting standards and collections, charge-off and recovery practices; • changes in experience, ability and depth of lending management and staff; • changes in national and local economic and business conditions and developments, including the condition of various market segments; • changes in the volume and severity of past due and classified loans and trends in the volume of non-accrual loans, TDRs and other loan modifications; • changes in the quality of the Company’s loan review system; • changes in the underlying collateral for collateral dependent loans; and • the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the bank’s existing portfolio. All such estimates and considerations may be susceptible to significant change. Loan losses are charged off against the allowance, while recoveries are credited to the allowance. A provision for credit losses is charged to income based on management’s periodic evaluation of the factors previously mentioned, as well as other pertinent factors. Evaluations are conducted at least quarterly and more frequently if deemed necessary. Under accounting guidance applicable to loans acquired with evidence of credit quality deterioration since origination, the excess of cash flows expected at acquisition over the estimated fair value is referred to as the accretable yield and is recognized in interest income over the remaining estimated life of the loans, using the effective-interest method. The difference between contractually required payments at acquisition and the cash flows expected to be collected at acquisition is referred to as the nonaccretable difference. Changes in the expected cash flows from the date of acquisition will either impact the accretable yield or result in a charge to the provision for credit losses. Subsequent decreases to expected principal cash flows will result in a charge to provision for credit losses and a corresponding increase to allowance for loan losses. Subsequent increases in expected principal cash flows will result in recovery of any previously recorded allowance for loan losses, to the extent applicable, and a reclassification from nonaccretable difference to accretable yield for any remaining increase. All changes in expected interest cash flows, including the impact of prepayments, will result in reclassifications to/from nonaccretable differences. In estimating expected losses, the Company evaluates loans for impairment in accordance ASC 310, “Receivables.” A loan is considered impaired when, based on current information and events, it is probable that a creditor will be unable to collect all amounts due pursuant to the contractual terms of the loan. Impaired loans include non-accrual loans, restructured loans or loans with principal and/or interest at risk, even if the loan is current with all payments of principal and interest. Impairment is measured by estimating the fair value of the loan based on the present value of expected cash flows, the market price of the loan, or the fair value of the underlying collateral less costs to sell. If the estimated fair value of the loan is less than the recorded book value, a valuation allowance is established as a component of the allowance for loan losses. For TDRs in which impairment is calculated by the present value of future cash flows, the Company records interest income representing the decrease in impairment resulting from the passage of time during the respective period, which differs from interest income from contractually required interest on these specific loans. The Company also maintains an allowance for lending-related commitments, specifically unfunded loan commitments and letters of credit, to provide for the risk of loss inherent in these arrangements. The allowance is computed using a methodology similar to that used to determine the allowance for loan losses. This allowance is included in other liabilities on the statement of condition while the corresponding provision for these losses is recorded as a component of the provision for credit losses. In conjunction with FDIC-assisted transactions, the Company entered into loss share agreements with the FDIC. Additional expected losses, to the extent such expected losses resulted in the recognition of an allowance for loan losses, increased the FDIC loss share asset or reduced any FDIC loss share liability. The allowance for loan losses for loans acquired in FDIC-assisted transactions was determined without giving consideration to the amounts recoverable through loss share agreements (since the loss share agreements are separately accounted for and thus presented “gross” on the balance sheet). On the Consolidated Statements of Income, the provision for credit losses was reported net of changes in the amount recoverable under the loss share agreements. Reductions to expected losses, to the extent such reductions to expected losses were the result of an improvement to the actual or expected cash flows from the covered assets, reduced the FDIC loss share asset or increased any FDIC loss share liability. Additions to expected losses required an increase to the allowance for loan losses, and a corresponding increase to the FDIC loss share asset or reduction to any FDIC loss share liability.
Mortgage Servicing Rights	Mortgage Servicing Rights MSRs are recorded in the Consolidated Statements of Condition at fair value in accordance with ASC 860, “Transfers and Servicing.” The Company originates mortgage loans for sale to the secondary market. Certain loans are originated and sold with servicing rights retained. MSRs associated with loans originated and sold, where servicing is retained, are capitalized at the time of sale at fair value based on the future net cash flows expected to be realized for performing the servicing activities, and included in other assets in the Consolidated Statements of Condition. The change in the fair value of MSRs is recorded as a component of mortgage banking revenue in non-interest income in the Consolidated Statements of Income. The Company measures the fair value of MSRs by stratifying the servicing rights into pools based on homogenous characteristics, such as product type and interest rate. The fair value of each servicing rights pool is calculated based on the present value of estimated future cash flows using a discount rate commensurate with the risk associated with that pool, given current market conditions. Estimates of fair value include assumptions about prepayment speeds, interest rates and other factors which are subject to change over time. Changes in these underlying assumptions could cause the fair value of MSRs to change significantly in the future.
Lease Investments	Lease Investments The Company’s investments in equipment and other assets held on operating leases are reported as lease investments, net. Rental income on operating leases is recognized as income over the lease term on a straight-line basis. Equipment and other assets held on operating leases is stated at cost less accumulated depreciation. Depreciation of the cost of the assets held on operating leases, less any residual value, is computed using the straight-line method over the term of the leases, which is generally seven years or less.
Premises and Equipment	Premises and Equipment Premises and equipment, including leasehold improvements, are stated at cost less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives of the related assets. Useful lives range from two to 15 years for furniture, fixtures and equipment, two to five years for software and computer-related equipment and seven to 39 years for buildings and improvements. Land improvements are amortized over a period of 15 years and leasehold improvements are amortized over the shorter of the useful life of the improvement or the term of the respective lease including any lease renewals deemed to be reasonably assured. Land and antique furnishings and artwork are not subject to depreciation. Expenditures for major additions and improvements are capitalized, and maintenance and repairs are charged to expense as incurred. Internal costs related to the configuration and installation of new software and the modification of existing software that provides additional functionality are capitalized. Long-lived depreciable assets are evaluated periodically for impairment when events or changes in circumstances indicate the carrying amount may not be recoverable. Impairment exists when the expected undiscounted future cash flows of a long-lived asset are less than its carrying value. In that event, a loss is recognized for the difference between the carrying value and the estimated fair value of the asset based on a quoted market price, if applicable, or a discounted cash flow analysis. Impairment losses are recognized in other non-interest expense.
FDIC Loss Share Asset (Liability)	FDIC Loss Share Asset (Liability) In conjunction with FDIC-assisted transactions, the Company entered into loss share agreements with the FDIC. These agreements covered losses incurred with respect to loans, foreclosed real estate and certain other assets. The loss share assets and liabilities were measured separately from the loan portfolios because they were not contractually embedded in the loans and were not transferable with the loans should the Company choose to dispose of them. Fair values at the acquisition dates were estimated based on projected cash flows available for loss-share based on the credit adjustments estimated for each loan pool and the loss share percentages. The loss share assets and liabilities were recorded as FDIC indemnification assets and other liabilities on the Consolidated Statements of Condition. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses reduced FDIC loss share assets or increased FDIC loss share liabilities. Reductions to expected losses, to the extent such reductions to expected losses were the result of an improvement to the actual or expected cash flows from the covered assets, also reduced FDIC loss share assets or increased FDIC loss share liabilities. In accordance with certain clawback provisions, the Company was required to reimburse the FDIC when actual losses were less than certain thresholds established for each loss share agreement. The balance of these estimated reimbursements and any related amortization were adjusted periodically for changes in the expected losses on covered assets. On the Consolidated Statements of Condition, estimated reimbursements from clawback provisions were recorded as a reduction to FDIC loss share assets or an increase to FDIC loss share liabilities. Although these assets and liabilities were contractual receivables from and payables to the FDIC, there were no contractual interest rates. Additional expected losses, to the extent such expected losses resulted in the recognition of an allowance for loan losses, increased FDIC loss share assets or reduced FDIC loss share liabilities. The corresponding amortization or accretion was recorded as a component of non-interest income on the Consolidated Statements of Income.
Other Real Estate Owned	Other Real Estate Owned Other real estate owned is comprised of real estate acquired in partial or full satisfaction of loans and is included in other assets. Other real estate owned is recorded at its estimated fair value less estimated selling costs at the date of transfer. Any excess of the related loan balance over the fair value less expected selling costs is charged to the allowance for loan losses. In contrast, any excess of the fair value less expected selling costs over the related loan balance is recorded as a recovery of prior charge-offs on the loan and, if any portion of the excess exceeds prior charge-offs, as an increase to earnings. Subsequent changes in value are reported as adjustments to the carrying amount and are recorded in other non-interest expense. Gains and losses upon sale, if any, are also charged to other non-interest expense. Other real estate owned is comprised of real estate acquired in partial or full satisfaction of loans and is included in other assets. Other real estate owned is recorded at its estimated fair value less estimated selling costs at the date of transfer, with any excess of the related loan balance over the fair value less expected selling costs charged to the allowance for loan losses. Subsequent changes in value are reported as adjustments to the carrying amount and are recorded in other non-interest expense. Gains and losses upon sale, if any, are also charged to other non-interest expense. Fair value is generally based on third party appraisals and internal estimates that are adjusted by a discount representing the estimated cost of sale and is therefore considered a Level 3 valuation.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill represents the excess of the cost of an acquisition over the fair value of net assets acquired. Other intangible assets represent purchased assets that also lack physical substance but can be distinguished from goodwill because of contractual or other legal rights or because the asset is capable of being sold or exchanged either on its own or in combination with a related contract, asset or liability. In accordance with accounting standards, goodwill is not amortized, but rather is tested for impairment on an annual basis or more frequently when events warrant, using a qualitative or quantitative approach. Intangible assets which have finite lives are amortized over their estimated useful lives and also are subject to impairment testing. Intangible assets which have indefinite lives are evaluated each reporting date to determine whether events and circumstances continue to support an indefinite useful life. If an indefinite useful life can no longer be supported for such asset, the intangible asset will begin amortization over the estimated useful life at that point of time. If an indefinite useful life can be supported, the asset is not amortized, but rather is tested for impairment on an annual basis or more frequently when events warrant, using a qualitative or quantitative approach. All of the Company’s intangible assets with finite lives are amortized over varying periods not exceeding twenty years. The core deposit intangibles recognized in connection with prior bank acquisitions are amortized over a ten -year period on an accelerated basis. The customer list intangibles recognized in connection with the purchase of life insurance premium finance assets in 2009 are being amortized over an 18 -year period on an accelerated basis while the customer list intangibles recognized in connection with prior acquisitions within the wealth management segment are being amortized over a period of up to ten -years on a straight-line basis.
Bank-Owned Life Insurance (BOLI)	Bank-Owned Life Insurance ("BOLI") The Company maintains BOLI on certain executives. BOLI balances are recorded at their cash surrender values and are included in other assets. Changes in the cash surrender values are included in non-interest income.
Derivative Instruments	Derivative Instruments The Company enters into derivative transactions principally to protect against the risk of adverse price or interest rate movements on the future cash flows or the value of certain assets and liabilities. The Company is also required to recognize certain contracts and commitments, including certain commitments to fund mortgage loans held-for-sale, as derivatives when the characteristics of those contracts and commitments meet the definition of a derivative. The Company accounts for derivatives in accordance with ASC 815, “Derivatives and Hedging,” which requires that all derivative instruments be recorded in the statement of condition at fair value. The accounting for changes in the fair value of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and further, on the type of hedging relationship. Derivative instruments designated in a hedge relationship to mitigate exposure to changes in the fair value of an asset or liability attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Derivative instruments designated in a hedge relationship to mitigate exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Formal documentation of the relationship between a derivative instrument and a hedged asset or liability, as well as the risk-management objective and strategy for undertaking each hedge transaction and an assessment of effectiveness is required at inception to apply hedge accounting. In addition, formal documentation of ongoing effectiveness testing is required to maintain hedge accounting. Fair value hedges are accounted for by recording the changes in the fair value of the derivative instrument and the changes in the fair value related to the risk being hedged of the hedged asset or liability on the statement of condition with corresponding offsets recorded in the income statement. The adjustment to the hedged asset or liability is included in the basis of the hedged item, while the fair value of the derivative is recorded as a freestanding asset or liability. Actual cash receipts or payments and related amounts accrued during the period on derivatives included in a fair value hedge relationship are recorded as adjustments to the interest income or expense recorded on the hedged asset or liability. Cash flow hedges are accounted for by recording the changes in the fair value of the derivative instrument on the statement of condition as either a freestanding asset or liability, with a corresponding offset recorded in other comprehensive income within shareholders’ equity, net of deferred taxes. Amounts are reclassified from accumulated other comprehensive income to interest expense in the period or periods the hedged forecasted transaction affects earnings. Under both the fair value and cash flow hedge scenarios, changes in the fair value of derivatives not considered to be highly effective in hedging the change in fair value or the expected cash flows of the hedged item are recognized in earnings as non-interest income during the period of the change. Derivative instruments that are not designated as hedges according to accounting guidance are reported on the statement of condition at fair value and the changes in fair value are recognized in earnings as non-interest income during the period of the change. Commitments to fund mortgage loans (i.e. interest rate locks) to be sold into the secondary market and forward commitments for the future delivery of these mortgage loans are accounted for as derivatives and are not designated in hedging relationships. Fair values of these mortgage derivatives are estimated based on changes in mortgage rates from the date of the commitments. Changes in the fair values of these derivatives are included in mortgage banking revenue. Forward currency contracts used to manage foreign exchange risk associated with certain assets are accounted for as derivatives and are not designated in hedging relationships. Foreign currency derivatives are recorded at fair value based on prevailing currency exchange rates at the measurement date. Changes in the fair values of these derivatives resulting from fluctuations in currency rates are recognized in earnings as non-interest income during the period of change. Periodically, the Company sells options to an unrelated bank or dealer for the right to purchase certain securities held within the banks’ investment portfolios (“covered call options”). These option transactions are designed primarily as an economic hedge to compensate for net interest margin compression by increasing the total return associated with holding the related securities as earning assets by using fee income generated from these options. These transactions are not designated in hedging relationships pursuant to accounting guidance and, accordingly, changes in fair values of these contracts, are reported in other non-interest income. Interest rate swaps designated as fair value hedges involve the payment of fixed amounts to a counterparty in exchange for the Company receiving variable payments over the life of the agreements without the exchange of the underlying notional amount. As of December 31, 2018 , the Company has fifteen interest rate swaps with an aggregate notional amount of $173.0 million that were designated as fair value hedges primarily associated with fixed rate commercial and industrial and commercial real estate loans as well as life insurance premium finance receivables. Three of these interest rate swaps with an aggregate notional amount of $55.9 million were effective starting after December 31, 2018. For derivatives designated and that qualify as fair value hedges, the net gain or loss from the entire change in the fair value of the derivative instrument is recognized in the same income statement line item as the earnings effect, including the net gain or loss, of the hedged item (interest income earned on fixed rate loans) when the hedged item affects earnings. The Company does not use derivatives for speculative purposes. Derivatives not designated as accounting hedges are used to manage the Company’s economic exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements of ASC 815. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings. Interest Rate Derivatives —The Company has interest rate derivatives, including swaps and option products, resulting from a service the Company provides to certain qualified borrowers. The Company’s banking subsidiaries execute certain derivative products (typically interest rate swaps) directly with qualified commercial borrowers to facilitate their respective risk management strategies. For example, these arrangements allow the Company’s commercial borrowers to effectively convert a variable rate loan to a fixed rate. In order to minimize the Company’s exposure on these transactions, the Company simultaneously executes offsetting derivatives with third parties. In most cases, the offsetting derivatives have mirror-image terms, which result in the positions’ changes in fair value substantially offsetting through earnings each period. However, to the extent that the derivatives are not a mirror-image and because of differences in counterparty credit risk, changes in fair value will not completely offset resulting in some earnings impact each period. Changes in the fair value of these derivatives are included in other non-interest income. The Company’s objectives in using interest rate derivatives are to add stability to net interest income and to manage its exposure to interest rate movements. To accomplish these objectives, the Company primarily uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without the exchange of the underlying notional amount. Interest rate collars designated as cash flow hedges involve the receipt of amounts in which the interest rate specified in the contract exceeds the agreed upon cap strike price or the payment of amounts in which the interest rate specified in the contract is below the agreed upon floor strike price at the end of each period. As of December 31, 2018 , the Company had three interest rate swap derivatives designated as cash flow hedges of variable rate deposits and one interest rate collar derivative designated as a cash flow hedge of variable rate debt. When the relationship between the hedged item and hedging instrument is highly effective at achieving offsetting changes in cash flows attributable to the hedged risk, changes in the fair value of these cash flow hedges are recorded in accumulated other comprehensive income and are subsequently reclassified to interest expense as interest payments are made on such variable rate deposits. The changes in fair value (net of tax) are separately disclosed in the Consolidated Statements of Comprehensive Income. Mortgage Banking Derivatives— These derivatives include interest rate lock commitments provided to customers to fund certain mortgage loans to be sold into the secondary market and forward commitments for the future delivery of such loans. It is the Company’s practice to enter into forward commitments for the future delivery of a portion of our residential mortgage loan production when interest rate lock commitments are entered into in order to economically hedge the effect of future changes in interest rates on its commitments to fund the loans as well as on its portfolio of mortgage loans held-for-sale. The Company’s mortgage banking derivatives have not been designated as being in hedge relationships. At December 31, 2018 , the Company had forward commitments to sell mortgage loans with an aggregate notional amount of approximately $481.6 million and interest rate lock commitments with an aggregate notional amount of approximately $235.8 million . The fair values of these derivatives were estimated based on changes in mortgage rates from the dates of the commitments. Changes in the fair value of these mortgage banking derivatives are included in mortgage banking revenue. Foreign Currency Derivatives— These derivatives include foreign currency contracts used to manage the foreign exchange risk associated with foreign currency denominated assets and transactions. Foreign currency contracts, which include spot and forward contracts, represent agreements to exchange the currency of one country for the currency of another country at an agreed-upon price on an agreed-upon settlement date. As a result of fluctuations in foreign currencies, the U.S. dollar-equivalent value of the foreign currency denominated assets or forecasted transactions increase or decrease. Gains or losses on the derivative instruments related to these foreign currency denominated assets or forecasted transactions are expected to substantially offset this variability. As of December 31, 2018 the Company held foreign currency derivatives with an aggregate notional amount of approximately $40.3 million . Other Derivatives— Periodically, the Company will sell options to a bank or dealer for the right to purchase certain securities held within the banks’ investment portfolios (covered call options). These option transactions are designed primarily to mitigate overall interest rate risk and to increase the total return associated with the investment securities portfolio. These options do not qualify as accounting hedges pursuant to ASC 815, and, accordingly, changes in fair value of these contracts are recognized as other non-interest income. The Company primarily enters into derivative financial instruments as part of its strategy to manage its exposure to changes in interest rates. Derivative instruments represent contracts between parties that result in one party delivering cash to the other party based on a notional amount and an underlying term (such as a rate, security price or price index) as specified in the contract. The amount of cash delivered from one party to the other is determined based on the interaction of the notional amount of the contract with the underlying term. Derivatives are also implicit in certain contracts and commitments. The derivative financial instruments currently used by the Company to manage its exposure to interest rate risk include: (1) interest rate swaps to manage the interest rate risk of certain fixed and variable rate assets and variable rate liabilities; (2) interest rate lock commitments provided to customers to fund certain mortgage loans to be sold into the secondary market; (3) forward commitments for the future delivery of such mortgage loans to protect the Company from adverse changes in interest rates and corresponding changes in the value of mortgage loans held-for-sale; and (4) covered call options to economically hedge specific investment securities and receive fee income effectively enhancing the overall yield on such securities to compensate for net interest margin compression. The Company also enters into derivatives (typically interest rate swaps) with certain qualified borrowers to facilitate the borrowers’ risk management strategies and concurrently enters into mirror-image derivatives with a third party counterparty, effectively making a market in the derivatives for such borrowers. Additionally, the Company enters into foreign currency contracts to manage foreign exchange risk associated with certain foreign currency denominated assets. The Company recognizes derivative financial instruments in the consolidated financial statements at fair value regardless of the purpose or intent for holding the instrument. The Company records derivative assets and derivative liabilities on the Consolidated Statements of Condition within accrued interest receivable and other assets and accrued interest payable and other liabilities, respectively. Changes in the fair value of derivative financial instruments are either recognized in income or in shareholders’ equity as a component of other comprehensive income depending on whether the derivative financial instrument qualifies for hedge accounting and, if so, whether it qualifies as a fair value hedge or cash flow hedge. As of January 1, 2018, the Company elected to early adopt ASU No. 2017-12, "Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities." Generally, changes in fair values of derivatives accounted for as fair value hedges are recorded in income in the same period and in the same income statement line as changes in the fair values of the hedged items that relate to the hedged risk(s). Changes in fair values of derivative financial instruments accounted for as cash flow hedges are recorded as a component of other comprehensive income, net of deferred taxes, and reclassified to earnings when the hedged transaction affects earnings. Changes in fair values of derivative financial instruments not designated in a hedging relationship pursuant to ASC 815 are reported in non-interest income during the period of the change. Derivative financial instruments are valued by a third party and are corroborated by comparison with valuations provided by the respective counterparties. Fair values of certain mortgage banking derivatives (interest rate lock commitments and forward commitments to sell mortgage loans) are estimated based on changes in mortgage interest rates from the date of the loan commitment. The fair value of foreign currency derivatives is computed based on changes in foreign currency rates stated in the contract compared to those prevailing at the measurement date.
Trust Assets, Assets Under Management and Brokerage Assets	Trust Assets, Assets Under Management and Brokerage Assets Assets held in fiduciary or agency capacity for customers are not included in the consolidated financial statements as they are not assets of Wintrust or its subsidiaries. Fee income is recognized on an accrual basis and is included as a component of non-interest income.
Income Taxes	Income Taxes Wintrust and its subsidiaries file a consolidated Federal income tax return. Income tax expense is based upon income in the consolidated financial statements rather than amounts reported on the income tax return. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using currently enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized as an income tax benefit or income tax expense in the period that includes the enactment date. Positions taken in the Company’s tax returns may be subject to challenge by the taxing authorities upon examination. In accordance with applicable accounting guidance, uncertain tax positions are initially recognized in the financial statements when it is more likely than not the positions will be sustained upon examination by the tax authorities. Such tax positions are both initially and subsequently measured as the largest amount of tax benefit that is greater than 50% likely being realized upon settlement with the tax authority, assuming full knowledge of the position and all relevant facts. Interest and penalties on income tax uncertainties are classified within income tax expense in the income statement. The tax effect of fair value adjustments on securities available-for-sale and derivative instruments in cash flow hedges are recorded directly to shareholders' equity as part of other comprehensive income (loss) and are reflected on the Consolidated Statements of Comprehensive Income. In addition, a tax benefit of $230,000 , related to stock-based compensation, reflecting the excess of realized tax benefits over expected tax benefits, was recorded directly to shareholders' equity in 2016.
Stock-Based Compensation Plans	Stock-Based Compensation Plans In accordance with ASC 718, “Compensation — Stock Compensation,” compensation cost is measured as the fair value of the awards on their date of grant. A Black-Scholes model is utilized to estimate the fair value of stock options and the market price of the Company’s stock at the date of grant is used to estimate the fair value of restricted stock awards. Compensation cost is recognized over the required service period, generally defined as the vesting period. For awards with graded vesting, compensation cost is recognized on a straight-line basis over the requisite service period for the entire award. Accounting guidance requires the recognition of stock based compensation for the number of awards that are ultimately expected to vest. As a result, recognized compensation expense for stock options and restricted share awards is reduced for estimated forfeitures prior to vesting. Forfeitures rates are estimated for each type of award based on historical forfeiture experience. Estimated forfeitures will be reassessed in subsequent periods and may change based on new facts and circumstances. The Company issues new shares to satisfy option exercises and vesting of restricted shares. The actual tax benefit realized upon the vesting of restricted shares and performance-based stock is based on the fair value of the shares on the issue date and the estimated tax benefit of the awards is based on fair value of the awards on the grant date. The actual tax benefit realized upon the vesting of restricted shares and performance-based stock in 2018 , 2017 and 2016 was $994,000 , $975,000 and $241,000 , respectively, more than the expected tax benefit for those shares. These differences in actual and expected tax benefits were recorded to tax expense in 2018 and 2017 and directly to shareholders’ equity in 2016 . As of December 31, 2018 , there was $15.4 million of total unrecognized compensation cost related to non-vested share based arrangements under the Plans. That cost is expected to be recognized over a weighted average period of approximately two years. The total fair value of shares vested during the years ended December 31, 2018 , 2017 and 2016 was $8.0 million , $8.9 million and $8.4 million , respectively.
Comprehensive Income	Comprehensive Income Comprehensive income consists of net income and other comprehensive income. Other comprehensive income includes unrealized gains and losses on available-for-sale debt securities, net of deferred taxes, changes in deferred gains and losses on investment securities transferred from available-for-sale debt securities to held-to-maturity debt securities, net of deferred taxes, adjustments related to cash flow hedges, net of deferred taxes and foreign currency translation adjustments, net of deferred taxes.
Stock Repurchases	Stock Repurchases The Company periodically repurchases shares of its outstanding common stock through open market purchases or other methods. Repurchased shares are recorded as treasury shares on the trade date using the treasury stock method, and the cash paid is recorded as treasury stock.
Foreign Currency Translation	Foreign Currency Translation The Company revalues assets, liabilities, revenue and expense denominated in non-U.S. currencies into U.S. dollars at the end of each month using applicable exchange rates. Gains and losses relating to translating functional currency financial statements for U.S. reporting are included in other comprehensive income. Gains and losses relating to the re-measurement of transactions to the functional currency are reported in the Consolidated Statements of Income.
New Accounting Pronouncements Adopted and Recent Accounting Pronouncements	New Accounting Pronouncements Adopted Revenue Recognition In May 2014, the FASB issued ASU No. 2014-09, which created “Revenue from Contracts with Customers (Topic 606),” to clarify the principles for recognizing revenue and develop a common revenue standard for customer contracts. This ASU provides guidance regarding how an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also added a new subtopic to the codification, ASC 340-40, “Other Assets and Deferred Costs: Contracts with Customers” to provide guidance on costs related to obtaining and fulfilling a customer contract. Furthermore, the new standard requires disclosure of sufficient information to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. At the time ASU No. 2014-09 was issued, the guidance was effective for fiscal years beginning after December 15, 2016. In July 2015, the FASB approved a deferral of the effective date by one year, which resulted in the guidance becoming effective for the Company as of January 1, 2018. The FASB continued to issue various updates to clarify and improve specific areas of ASU No. 2014-09. In March 2016, the FASB issued ASU No. 2016-08, “Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net),” to clarify the implementation guidance within ASU No. 2014-09 surrounding principal versus agent considerations and its impact on revenue recognition. In April 2016, the FASB issued ASU No. 2016-10, “Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing,” to also clarify the implementation guidance within ASU No. 2014-09 related to these two topics. In May 2016, the FASB issued ASU No. 2016-11, “Revenue Recognition (Topic 605) and Derivative and Hedging (Topic 815): Rescission of SEC Guidance Because of Accounting Standards Updates 2014-09 and 2014-16 Pursuant to Staff Announcements at the March 3, 2016 EITF Meeting,” to remove certain areas of SEC Staff Guidance from those specific Topics. In May 2016 and December 2016, the FASB issued ASU 2016-12, “Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients” and ASU 2016-20, “Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers,” to clarify specific aspects of implementation, including the collectability criterion, exclusion of sales taxes collected from a transaction price, noncash consideration, contract modifications, completed contracts at transition, the applicability of loan guarantee fees, impairment of capitalized contract costs and certain disclosure requirements. In February 2017, the FASB issued ASU No. 2017-05, “Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets,” to clarify the implementation guidance within ASU No. 2014-09 surrounding transfers of nonfinancial assets, including partial sales of such assets, and its impact on revenue recognition. Like ASU No. 2014-09, this guidance became effective for the Company starting January 1, 2018. The Company adopted ASU No. 2014-09 and all subsequent updates issued to clarify and improve specific areas of this ASU as of January 1, 2018. As certain significant revenue sources related to financial instruments such as interest income are considered not in-scope, the new guidance did not have a significant impact on the Company's consolidated financial statements. Revenue sources impacted by the new guidance include brokerage and trust and asset management fees from the wealth management business unit, card-based fees, deposit-related fees and other non-interest income. During implementation, the Company reviewed specific contracts with customers across these various sources of revenue. Reviews of such contracts assisted in identifying any characteristics of such contracts that could result in a change in the Company's current practices for recognition of revenue and recognition of costs incurred to obtain or fulfill such contracts. After review of such contracts, the Company identified no indication within the terms of such contracts that a significant change in the Company's current practices and accounting policies was necessary. The Company elected to adopt the new guidance using the modified retrospective approach applied to all contracts as of the date of initial application at January 1, 2018. Electing the modified retrospective approach resulted in no cumulative effect adjustment to the opening balance of retained earnings at the date of initial application. Additional disclosures have been added in accordance with the new guidance. See Note 15 – Revenue from Contracts with Customers for discussion of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. Financial Instruments In January 2016, the FASB issued ASU No. 2016-01, “Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities,” to improve the accounting for financial instruments. This ASU requires equity securities with readily determinable fair values to be measured at fair value with changes recognized in net income. Such equity securities with readily determinable fair values are no longer classified as available-for-sale debt securities or trading securities within the consolidated financial statements of an entity. Additionally, this ASU requires the separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the accompanying notes to the financial statements. The Company adopted this guidance as of January 1, 2018. For equity securities with a readily determinable fair value, this guidance was applied under a modified retrospective approach with a cumulative-effect adjustment to the balance sheet as of the beginning of the fiscal year of adoption. As of January 1, 2018, the Company reclassified approximately $1.9 million from accumulated other comprehensive income, related to previously recognized unrealized gains, net of deferred taxes, from equity securities with readily determinable fair values, to retained earnings. Equity securities with readily determinable fair values are presented separate from available-for-sale debt securities and trading securities within the Company's Consolidated Statements of Condition prospectively as of the effective date. Equity securities without readily determinable fair values are included within accrued interest receivable and other assets within the Company's Consolidated Statements of Condition. See Note 5, “Investment Securities” for further discussion of equity securities with and without readily determinable fair values. In January 2018, the FASB issued ASU No. 2018-03, “Technical Corrections and Improvements to Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities,” to clarify certain aspects of the guidance issued in ASU No. 2016-01, including aspects of equity securities without a readily determinable fair value. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years beginning after June 15, 2018. Early adoption is permitted. As these clarifications did not have a material impact on the Company's consolidated financial statements, the Company elected to early adopt this guidance as of January 1, 2018. Derivatives In August 2017, the FASB issued ASU No. 2017-12, “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities,” to improve the financial reporting of hedging relationships to better align the economic results of an entity’s risk management activities and disclosures within its financial statements. In addition, this ASU makes certain targeted improvements to simplify the application of the hedge accounting, including to derivative instruments as well as allow a one-time election to reclassify fixed-rate, prepayable debt securities from a held-to-maturity classification to an available-for-sale classification. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Guidance related to existing cash flow hedges and, if elected, fair value hedges is to be applied under a modified retrospective approach and guidance related to amended presentation and disclosures is to be applied under a prospective approach. Early adoption is permitted as of the beginning of an annual period that has not been issued or made available for issuance. The Company elected to early adopt this guidance as of January 1, 2018. See Note 21 - Derivative Financial Instruments for further discussion of early adoption of this guidance. The impact of early adoption on the financial statements included the following: • As allowed under the guidance, for certain existing derivative instruments designated as fair value hedges, the Company transitioned the measurement methodology for the related hedged item (loans) to be in accordance with the guidance without dedesignation of the hedging relationship. This resulted in a negative cumulative basis adjustment to loans of $116,000 with a corresponding adjustment to retained earnings. • No fixed-rate, prepayable held-to-maturity securities were transferred to an available-for-sale classification. • The entire change in the hedging instrument included in the assessment of hedge effectiveness of fair value hedges is presented in the same income statement line as the current impact of the effective portion of such hedge, or interest income and interest expense for interest rate hedging. The Company has previously recognized this ineffectiveness within non-interest income. In October 2018, the FASB issued ASU No. 2018-16, “Derivatives and Hedging (Topic 815): Inclusion of the Secured Overnight Financing Rate (SOFR) Overnight Index Swap (OIS) Rate as a Benchmark Interest Rate for Hedge Accounting Purposes,” to permit the use of the OIS rate based on SOFR as a U.S. benchmark interest rate for hedge accounting purposes. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied prospectively for qualifying new or redesignated hedging relationships entered into on or after the date of adoption. Early adoption is permitted and the Company has early adopted ASU 2018-16 in 2018. Statement of Cash Flows In August 2016, the FASB issued ASU No. 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the FASB Emerging Issues Task Force),” to clarify the presentation of specific types of cash flow receipts and payments, including the payment of debt prepayment or debt extinguishment costs, contingent consideration cash payments paid subsequent to the acquisition date and proceeds from settlement of BOLI policies. This guidance became effective as of January 1, 2018 and was applied under a retrospective approach resulting in additional disclosure, including cash payments made to settle contingent consideration liabilities recognized in prior business combinations. In November 2016, the FASB issued ASU No. 2016-18 “Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force),” to clarify the classification and presentation of changes in restricted cash on the statement of cash flows. This guidance became effective as of January 1, 2018 and did not have a material impact on the Company. Income Taxes In October 2016, the FASB issued ASU No. 2016-16, “Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory,” to improve the accounting for intra-entity transfers of assets other than inventory. This ASU allows the recognition of current and deferred income taxes for such transfers prior to the subsequent sale of the transferred assets to an outside party. Initial recognition of current and deferred income taxes is currently prohibited for intra-entity transfers of assets other than inventory. This guidance became effective as of January 1, 2018 and did not have a material impact on the Company. The Tax Act was enacted on December 22, 2017, and the Company recognized a provisional tax benefit of $7.6 million in 2017 to reflect the impact of the Tax Act, primarily reflecting estimated effects of a lower federal income tax rate on its net deferred tax liabilities and a transition tax due on the deferred earnings of the Company's Canadian subsidiary. Estimates were made in good faith and were subject to change as additional information and interpretive guidance regarding provisions of the Tax Act became available. Staff Accounting Bulletin 118 provided a measurement period, not to extend beyond one year from the date of enactment, during which a company could complete the accounting for the impacts of the Tax Act. In 2018, the Company finalized the provisional amounts recorded for the year ended December 31, 2017 related to the Tax Act and recorded an additional net tax benefit of $1.2 million . Business Combinations In January 2017, the FASB issued ASU No. 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business,” to improve such definition and, as a result, assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or as business combinations. The definition of a business impacts many areas of accounting including acquisitions, disposals, goodwill and consolidation. This guidance became effective as of January 1, 2018 and was applied under a prospective approach. See Note 7, “Business Combinations and Asset Acquisitions” for further discussion of business acquisitions occurring in 2018. Compensation In March 2017, the FASB issued ASU No. 2017-07, “Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” to improve the presentation of net periodic pension cost and net periodic post-retirement benefit cost. An entity will be required to report the service cost component of such costs in the same line item or items as other compensation costs related to services rendered. Additionally, only the service cost component will be eligible for capitalization when applicable. This guidance became effective as of January 1, 2018 and was applied under a retrospective approach related to presentation of the service cost component and a prospective approach related to capitalization of such costs. Adoption of this guidance did not have a material impact on the Company's consolidated financial statements. In May 2017, the FASB issued ASU No. 2017-09, “Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting,” to clarify when modification accounting is appropriate for changes to the terms and conditions of a share-based payment award. An entity will be required to account for such changes as a modification unless certain criteria is met. This guidance became effective as of January 1, 2018 and was applied under a prospective approach for awards modified on or after the adoption date. Adoption of this guidance did not have a material impact on the Company's consolidated financial statements. Accumulated Other Comprehensive Income (Loss) In February 2018, the FASB issued ASU No. 2018-02, “Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income,” to allow a reclassification from accumulated other comprehensive income to retained earnings related to the stranded tax effects within other comprehensive income resulting from the Federal income tax rate reduction in the Tax Act. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied either in the period of adoption or retrospectively to each period or periods in which the effect of the Tax Act is recognized. Early adoption is permitted as of the beginning of an annual period that has not been issued or made available for issuance. The Company elected to early adopt this guidance as of January 1, 2018 and applied such reclassification in the current period (period of adoption). As of January 1, 2018, the Company reclassified a stranded tax credit of $3.0 million from accumulated other comprehensive income to retained earnings. The Company has a policy for releasing the income tax effects from accumulated other comprehensive income using an individual security approach. Leases In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842),” to improve transparency and comparability across entities regarding leasing arrangements. This ASU requires the recognition of a separate lease liability representing the required discounted lease payments over the lease term and a separate lease asset representing the right to use the underlying asset during the same lease term. Further, this ASU provides clarification regarding the identification of certain components of contracts that would represent a lease as well as requires additional disclosures to the notes of the financial statements. Additionally, in January 2018, the FASB issued ASU No. 2018-01, "Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842," to permit an entity to elect an optional practical expedient to not evaluate under Topic 842 land easements that exist or expired before the entity's adoption of Topic 842 and that were not previously accounted for as leases under existing accounting guidance. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach, including the option to apply certain practical expedients. The FASB has continued to issue various updates to clarify and improve specific areas of ASU No. 2016-02. In July 2018, the FASB issued ASU No. 2018-10, “Codification Improvements to Topic 842, Leases,” to clarify the implementation guidance within ASU No. 2016-02 surrounding narrow aspects of Topic 842, including lessee reassessment of lease classifications, the rate implicit in a lease, lessor reassessment of lease terms and purchase options and variable lease payments that depend on an index or a rate. Also, in July 2018, the FASB issued ASU No. 2018-11, “Leases (Topic 842): Targeted Improvements,” to clarify the implementation guidance within ASU No. 2016-02 surrounding comparative period reporting requirements for initial adoption as well as separating lease and non-lease components in a contract and allocating consideration in the contract to the separate components. Also, in December 2018, the FASB issued ASU No. 2018-20, “Leases (Topic 842): Narrow-Scope Improvements for Lessors,” to clarify the implementation guidance within ASU No. 2016-02 surrounding specific aspects of lessor accounting. Like ASU No. 2016-02, this guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. For leasing arrangements in which the Company is a lessee, the Company will primarily recognize separate lease liabilities and right to use assets related to certain banking facilities under operating lease agreements . Other leasing arrangements in which the Company will recognize separate lease liabilities and right to use assets include the use of signage related to certain sponsorships and other agreements, and certain automatic teller machines. The impact of adoption on the financial statements primarily includes the following: • The Company expects to utilize the following transition elections and practical expedients: ◦ Optional transition method to apply the new guidance at the date of adoption (i.e. January 1, 2019) and continue applying current lease accounting guidance for comparative periods (i.e. fiscal years 2018 and 2017). ◦ For lessee arrangements of certain banking facilities, the Company expects to elect the practical expedient to not separate non-lease components from lease components and instead to account for each separate lease and non-lease component as a single lease component. ◦ A package of practical expedients applied to leases existing prior to the effective date that must all be elected together and allow a Company to not reassess: ▪ whether any expiring or existing contracts are or contain a lease; ▪ lease classification for any expired or existing leases; and ▪ whether initial direct costs for any expired or existing leases qualify for capitalization. ◦ A practical expedient that will permit an entity to continue applying its current policy for accounting for expired or existing land easements. ◦ An accounting policy election for short-term leases (i.e. terms of 12 months or less with no purchase option expected to be exercised) to apply accounting similar to ASC 840, specifically to not recognize separate lease liabilities and right to use assets . • The Company expects to recognize at the effective date a right of use asset on the Consolidated Statements of Condition between $150.0 million and $190.0 million . Allowance for Credit Losses In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” to replace the current incurred loss methodology for recognizing credit losses, which delays recognition until it is probable a loss has been incurred, with a methodology that reflects an estimate of all expected credit losses and considers additional reasonable and supportable forecasted information when determining credit loss estimates. This impacts the calculation of an allowance for credit losses for all financial assets measured under the amortized cost basis, including held-to-maturity debt securities and PCI loans at the time of and subsequent to acquisition. Additionally, credit losses related to available-for-sale debt securities would be recorded through the allowance for credit losses and not as a direct adjustment to the amortized cost of the securities. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. The FASB has continued to issue various updates to clarify and improve specific areas of ASU No. 2016-13. In November 2018, the FASB issued ASU No. 2018-19, “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” to clarify the implementation guidance within ASU No. 2016-13 surrounding narrow aspects of Topic 326, including the impact of the guidance on operating lease receivables. Like ASU No. 2016-13, this guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. The Company is currently evaluating the impact of adopting this new guidance on the consolidated financial statements as well as the impact on current systems and processes. Specifically, the Company has established a committee consisting of individuals from the various areas of the Company tasked with transitioning to the new requirements. At this time, the Company is finalizing potential accounting policy elections and modeling methodologies for estimating expected credit losses using reasonable and supportable forecast information. Additionally, the Company is utilizing certain historical data and a previously selected platform to build, store, execute and determine the financial impact. Controls and processes are also being designed for the continued implementation process and after the effective date. Goodwill In January 2017, the FASB issued ASU No. 2017-04, “Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment,” to simplify the subsequent measurement of goodwill. When the carrying amount of a reporting unit exceeds its fair value, an entity would no longer be required to determine goodwill impairment by assigning the fair value of a reporting unit to all of its assets and liabilities as if that reporting unit was acquired in a business combination. Goodwill impairment would be recognized according to the excess of the carrying amount of the reporting unit over the calculated fair value of such unit. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied under a prospective approach. The Company does not expect this guidance to have a material impact on the Company's consolidated financial statements. Amortization of Premium on Certain Debt Securities In March 2017, the FASB issued ASU No. 2017-08, “Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities,” to amend the amortization period for certain purchased callable debt securities held at a premium. The amortization period for such securities will be shortened to the earliest call date. This guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and is to be applied under a modified retrospective approach. Early adoption is permitted as of the beginning of an annual period that has not been issued or made available for issuance. The Company did not early adopt this guidance as of January 1, 2018. The Company has evaluated adoption of this guidance and determined it will not have a material impact on the consolidated financial statements. Fair Value Measurement In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirement for Fair Value Measurement,” to modify disclosure requirements on fair value measurements and inputs. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied prospectively or retrospectively depending upon the disclosure requirement. Early adoption is permitted. The Company does not expect this guidance to have a material impact on the Company's consolidated financial statements. Intangibles In August 2018, the FASB issued ASU No. 2018-15, “Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract,” to align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with similar requirements related to implementation costs incurred to develop or obtain internal-use software. In addition, the amendment requires any capitalized implementation costs related to a hosting arrangement to be expensed over the term of the hosting arrangement. This guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is to be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. Early adoption is permitted, including adoption in any interim period. The Company is currently evaluating the impact of adopting this new guidance on the consolidated financial statements.
Finance, Loans and Leases Receivable	Certain premium finance receivables are recorded net of unearned income.
Receivables	These amounts include accretion from both covered and non-covered loans, and are included together within interest and fees on loans in the Consolidated Statements of Income.
Finance, Loan and Lease Receivables, Held-for-investment, Allowance and Nonperforming Loans, Allowance	As a result of this initial review by the Company’s Managed Asset Division, the credit risk rating is reviewed and a portion of the outstanding loan balance may be deemed uncollectible or an impairment reserve may be established. The Company’s impairment analysis utilizes an independent re-appraisal of the collateral (unless such a third-party evaluation is not possible due to the unique nature of the collateral, such as a closely-held business or thinly traded securities). In the case of commercial real estate collateral, an independent third party appraisal is ordered by the Company’s Real Estate Services Group to determine if there has been any change in the underlying collateral value. These independent appraisals are reviewed by the Real Estate Services Group and sometimes by independent third party valuation experts and may be adjusted depending upon market conditions. Through the credit risk rating process, loans are reviewed to determine if they are performing in accordance with the original contractual terms. If the borrower has failed to comply with the original contractual terms, further action may be required by the Company, including a downgrade in the credit risk rating, movement to non-accrual status, a charge-off or the establishment of a specific impairment reserve. If the Company determines that a loan amount or portion thereof is uncollectible the loan’s credit risk rating is immediately downgraded to an 8 or 9 and the uncollectible amount is charged-off. Any loan that has a partial charge-off continues to be assigned a credit risk rating of an 8 or 9 for the duration of time that a balance remains outstanding. The Company undertakes a thorough and ongoing analysis to determine if additional impairment and/or charge-offs are appropriate and to begin a workout plan for the credit to minimize actual losses. If, based on current information and events, it is probable that the Company will be unable to collect all amounts due to it according to the contractual terms of the loan agreement, a specific impairment reserve is established. In determining the appropriate charge-off for collateral-dependent loans, the Company considers the results of appraisals for the associated collateral.
Loans and Leases Receivable, Nonperforming Loan and Lease	The Company’s Problem Loan Reporting system includes all loans with credit risk ratings of 6 through 9. This system is designed to provide an on-going detailed tracking mechanism for each problem loan. Once management determines that a loan has deteriorated to a point where it has a credit risk rating of 6 or worse, the Company’s Managed Asset Division performs an overall credit and collateral review. As part of this review, all underlying collateral is identified and the valuation methodology is analyzed and tracked. As a result of this initial review by the Company’s Managed Asset Division, the credit risk rating is reviewed and a portion of the outstanding loan balance may be deemed uncollectible or an impairment reserve may be established. The Company’s impairment analysis utilizes an independent re-appraisal of the collateral (unless such a third-party evaluation is not possible due to the unique nature of the collateral, such as a closely-held business or thinly traded securities). In the case of commercial real estate collateral, an independent third party appraisal is ordered by the Company’s Real Estate Services Group to determine if there has been any change in the underlying collateral value. These independent appraisals are reviewed by the Real Estate Services Group and sometimes by independent third party valuation experts and may be adjusted depending upon market conditions. Through the credit risk rating process, loans are reviewed to determine if they are performing in accordance with the original contractual terms. If the borrower has failed to comply with the original contractual terms, further action may be required by the Company, including a downgrade in the credit risk rating, movement to non-accrual status, a charge-off or the establishment of a specific impairment reserve. If the Company determines that a loan amount or portion thereof is uncollectible the loan’s credit risk rating is immediately downgraded to an 8 or 9 and the uncollectible amount is charged-off. Any loan that has a partial charge-off continues to be assigned a credit risk rating of an 8 or 9 for the duration of time that a balance remains outstanding. The Company undertakes a thorough and ongoing analysis to determine if additional impairment and/or charge-offs are appropriate and to begin a workout plan for the credit to minimize actual losses. If, based on current information and events, it is probable that the Company will be unable to collect all amounts due to it according to the contractual terms of the loan agreement, a specific impairment reserve is established. In determining the appropriate charge-off for collateral-dependent loans, the Company considers the results of appraisals for the associated collateral. Non-performing loans include all non-accrual loans (8 and 9 risk ratings) as well as loans 90 days past due and still accruing interest, excluding PCI loans. The remainder of the portfolio is considered performing under the contractual terms of the loan agreement.
Loans and Leases Receivable, Troubled Debt Restructuring	The Company’s approach to restructuring loans, excluding PCI loans, is built on its credit risk rating system which requires credit management personnel to assign a credit risk rating to each loan. In each case, the loan officer is responsible for recommending a credit risk rating for each loan and ensuring the credit risk ratings are appropriate. These credit risk ratings are then reviewed and approved by the bank’s chief credit officer and/or concurrence credit officer. Credit risk ratings are determined by evaluating a number of factors including a borrower’s financial strength, cash flow coverage, collateral protection and guarantees. The Company’s credit risk rating scale is one through ten with higher scores indicating higher risk. In the case of loans rated six or worse following modification, the Company’s Managed Assets Division evaluates the loan and the credit risk rating and determines that the loan has been restructured to be reasonably assured of repayment and of performance according to the modified terms and is supported by a current, well-documented credit assessment of the borrower’s financial condition and prospects for repayment under the revised terms. A modification of a loan, excluding PCI loans, with an existing credit risk rating of 6 or worse or a modification of any other credit, which will result in a restructured credit risk rating of 6 or worse, must be reviewed for possible TDR classification. In that event, our Managed Assets Division conducts an overall credit and collateral review. A modification of these loans is considered to be a TDR if both (1) the borrower is experiencing financial difficulty and (2) for economic or legal reasons, the bank grants a concession to a borrower that it would not otherwise consider. The modification of a loan, excluding PCI loans, where the credit risk rating is 5 or better both before and after such modification is not considered to be a TDR. Based on the Company’s credit risk rating system, it considers that borrowers whose credit risk rating is 5 or better are not experiencing financial difficulties and therefore, are not considered TDRs. All credits determined to be a TDR will continue to be classified as a TDR in all subsequent periods, unless the borrower has been in compliance with the loan’s modified terms for a period of six months (including over a calendar year-end) and the current interest rate represents a market rate at the time of restructuring. The Managed Assets Division, in consultation with the respective loan officer, determines whether the modified interest rate represented a current market rate at the time of restructuring. Using knowledge of current market conditions and rates, competitive pricing on recent loan originations, and an assessment of various characteristics of the modified loan (including collateral position and payment history), an appropriate market rate for a new borrower with similar risk is determined. If the modified interest rate meets or exceeds this market rate for a new borrower with similar risk, the modified interest rate represents a market rate at the time of restructuring. Additionally, before removing a loan from TDR classification, a review of the current or previously measured impairment on the loan and any concerns related to future performance by the borrower is conducted. If concerns exist about the future ability of the borrower to meet its obligations under the loans based on a credit review by the Managed Assets Division, the TDR classification is not removed from the loan. TDRs are reviewed at the time of modification and on a quarterly basis to determine if a specific reserve is necessary. The carrying amount of the loan is compared to the expected payments to be received, discounted at the loan’s original rate, or for collateral dependent loans, to the fair value of the collateral. Any shortfall is recorded as a specific reserve. The Company, in accordance with ASC 310-10, continues to individually measure impairment of these loans after the TDR classification is removed. Each TDR was reviewed for impairment at December 31, 2018 and approximately $2.1 million of impairment was present and appropriately reserved for through the Company’s normal reserving methodology in the Company’s allowance for loan losses. For TDRs in which impairment is calculated by the present value of future cash flows, the Company records interest income representing the decrease in impairment resulting from the passage of time during the respective period, which differs from interest income from contractually required interest on these specific loans. For the years ended December 31, 2018 and 2017 , the Company recorded $113,000 and $207,000 , respectively, in interest income representing this decrease in impairment. TDRs may arise in which, due to financial difficulties experienced by the borrower, the Company obtains through physical possession one or more collateral assets in satisfaction of all or part of an existing credit. Once possession is obtained, the Company reclassifies the appropriate portion of the remaining balance of the credit from loans to OREO, which is included within other assets in the Consolidated Statements of Condition. For any residential real estate property collateralizing a consumer mortgage loan, the Company is considered to possess the related collateral only if legal title is obtained upon completion of foreclosure, or the borrower conveys all interest in the residential real estate property to the Company through completion of a deed in lieu of foreclosure or similar legal agreement. At December 31, 2018 , the Company had $4.9 million of foreclosed residential real estate properties included within OREO. Further, the recorded investment in residential mortgage loans secured by residential real estate properties for which foreclosure proceedings are in process totaled $14.4 million and $9.8 million at December 31, 2018 and 2017, respectively.
Transfers and Servicing of Financial Assets, Servicing of Financial Assets	The Company recognizes MSR assets upon the sale of residential real estate loans to external third parties when it retains the obligation to service the loans and the servicing fee is more than adequate compensation. The initial recognition of MSR assets from loans sold with servicing retained and subsequent changes in fair value of all MSRs are recognized in mortgage banking revenue. MSRs are subject to changes in value from actual and expected prepayment of the underlying loans. The Company does not specifically hedge the value of its MSRs. Fair values are determined by using a discounted cash flow model that incorporates the objective characteristics of the portfolio as well as subjective valuation parameters that purchasers of servicing would apply to such portfolios sold into the secondary market. The subjective factors include loan prepayment speeds, discount rates, servicing costs and other economic factors. The Company uses a third party to assist in the valuation of MSRs.
Deteriorated Loans Transferred In	Purchased loans acquired in a business combination are recorded at estimated fair value on their purchase date. For PCI loans, expected future cash flows at the purchase date in excess of the fair value of loans are recorded as interest income over the life of the loans if the timing and amount of the future cash flows is reasonably estimable (“accretable yield”). The difference between contractually required payments and the cash flows expected to be collected at acquisition is referred to as the non-accretable difference and represents probable losses in the portfolio. In determining the acquisition date fair value of PCI loans, and in subsequent accounting, the Company aggregates these purchased loans into pools of loans by common risk characteristics, such as credit risk rating and loan type. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. Subsequent decreases to the expected cash flows will result in a provision for loan losses. The Company purchased a portfolio of life insurance premium finance receivables in 2009. These purchased life insurance premium finance receivables are valued on an individual basis. If credit related conditions deteriorate, an allowance related to these loans will be established as part of the provision for credit losses.
Disclosure about Offsetting Assets and Liabilities	The Company records securities sold under repurchase agreements at their gross value and does not offset positions on the Consolidated Statements of Condition.
Repurchase Agreements, Collateral	Securities pledged for customer balances in sweep accounts and short-term borrowings from brokers are maintained under the Company’s control and consist of U.S. Government agency and mortgage-backed securities. These securities are included in the available-for-sale and held-to-maturity securities portfolios as reflected on the Company’s Consolidated Statements of Condition.
Debt	FHLB advances are stated at par value of the debt adjusted for unamortized prepayment fees paid at the time of prior restructurings of FHLB advances and unamortized fair value adjustments recorded in connection with advances acquired through acquisitions and debt issuance costs. Unamortized prepayment fees are amortized as an adjustment to interest expense using the effective interest method. In connection with the issuance of subordinated notes in 2014, the Company incurred costs totaling $1.3 million . These costs are a direct deduction from the carrying amount of the subordinated notes and are amortized to interest expense using the effective interest method. The remaining $11.8 million within secured borrowings at December 31, 2018 represents other sold interests in certain loans by the Company that were not considered sales and, as such, related proceeds received are reflected on the Company’s Consolidated Statements of Condition as a secured borrowing owed to the various unrelated third parties. These transactions were not considered sales of receivables and, as such, related proceeds received are reflected on the Company’s Consolidated Statements of Condition as a secured borrowing owed to the unrelated third party, net of unamortized debt issuance costs, and translated to the Company’s reporting currency as of the respective date. At December 31, 2018, the translated balance of the secured borrowing totaled $139.3 million compared to $135.1 million at December 31, 2017.
Junior Subordinated Debentures	The Trusts are reported in the Company’s consolidated financial statements as unconsolidated subsidiaries. Accordingly, in the Consolidated Statements of Condition, the junior subordinated debentures issued by the Company to the Trusts are reported as liabilities and the common securities of the Trusts, all of which are owned by the Company, are included in investment securities.
Income Tax Uncertainties	At December 31, 2018 , the Company had $9.3 million of unrecognized tax benefits related to uncertain tax positions that, if recognized, would impact the effective tax rate. Interest and penalties on unrecognized tax positions are recorded in income tax expense. Total interest income accrued at December 31, 2018 and 2017 on unrecognized tax benefits was $1.1 million and $921,000 , respectively, net of tax effect. Interest and penalties are included in the liability for uncertain tax positions, but are not included in the unrecognized tax benefits rollforward presented above. The Company does not expect the total amount of unrecognized tax benefits to significantly increase or decrease in the next twelve months. The Company and its subsidiaries are subject to U.S. federal income tax as well as income tax in numerous state jurisdictions and in Canada. In the ordinary course of business we are routinely subject to audit by the taxing authorities of these jurisdictions. Currently, the Company's U.S. federal income tax returns are open and subject to audit for the 2015 tax return year forward, and in general, the Company's state income tax returns are open and subject to audit from the 2015 tax return year forward, subject to individual state statutes of limitation. The Company's Canadian subsidiary's Canadian income tax returns are also subject to audit for the 2015 tax return year forward.
Compensation Related Costs	Stock-based compensation is measured as the fair value of an award on the date of grant, and the measured cost is recognized over the period which the recipient is required to provide service in exchange for the award. The fair values of restricted share and performance-based stock awards are determined based on the average of the high and low trading prices on the grant date, and the fair value of stock options is estimated using a Black-Scholes option-pricing model that utilizes the assumptions outlined in the following table. Option-pricing models require the input of highly subjective assumptions and are sensitive to changes in the option’s expected life and the price volatility of the underlying stock, which can materially affect the fair value estimate. Options granted since the inception of the LTIP in 2011 were primarily granted as LTIP awards. Expected life of the options granted since the inception of the LTIP awards has been based on the safe harbor rule of the SEC Staff Accounting Bulletin No. 107 “Share-Based Payment” as the Company believes historical exercise data may not provide a reasonable basis to estimate the expected term of these options. Expected stock price volatility is based on historical volatility of the Company’s common stock, which correlates with the expected life of the options, and the risk-free interest rate is based on comparable U.S. Treasury rates. Management reviews and adjusts the assumptions used to calculate the fair value of an option on a periodic basis to better reflect expected trends. The following table presents the weighted average assumptions used to determine the fair value of options granted in the year ended December 31, 2016 . No options were granted in the years ended December 31, 2018 and 2017. 2016 Expected dividend yield 0.9 % Expected volatility 25.2 % Risk-free rate 1.3 % Expected option life (in years) 4.5 Stock based compensation is recognized based on the number of awards that are ultimately expected to vest. Forfeitures are estimated based on historical forfeiture experience. For performance-based stock awards, an estimate is made of the number of shares expected to vest as a result of actual performance against the performance criteria to determine the amount of compensation expense to be recognized. The estimate is reevaluated quarterly and total compensation expense is adjusted for any change in the current period.
Liability Reserve Estimate	The liability for estimated losses on repurchase and indemnification claims for residential mortgage loans previously sold to investors was $2.4 million and $3.0 million at December 31, 2018 and 2017 , respectively, and was included in other liabilities on the Consolidated Statements of Condition. Management maintains a liability for estimated losses on loans expected to be repurchased or on which indemnification is expected to be provided and regularly evaluates the adequacy of this recourse liability based on trends in repurchase and indemnification requests, actual loss experience, known and inherent risks in the loans, and current economic conditions.
Derivatives, Offsetting Fair Value Amounts	The Company records interest rate derivatives subject to master netting agreements at their gross value and does not offset derivative assets and liabilities on the Consolidated Statements of Condition.
Fair Value of Financial Instruments	The Company measures, monitors and discloses certain of its assets and liabilities on a fair value basis. These financial assets and financial liabilities are measured at fair value in three levels, based on the markets in which the assets and liabilities are traded and the observability of the inputs used to determine fair value. These levels are: • Level 1 — unadjusted quoted prices in active markets for identical assets or liabilities. • Level 2 — inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability or inputs that are derived principally from or corroborated by observable market data by correlation or other means. • Level 3 — significant unobservable inputs that reflect the Company’s own assumptions that market participants would use in pricing the assets or liabilities. Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation. A financial instrument’s categorization within the above valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the assets or liabilities. Following is a description of the valuation methodologies used for the Company’s assets and liabilities measured at fair value on a recurring basis. Available-for-sale debt securities, trading account securities and equity securities with readily determinable fair value —Fair values for available-for-sale debt securities, trading account securities and equity securities with readily determinable fair value are typically based on prices obtained from independent pricing vendors. Securities measured with these valuation techniques are generally classified as Level 2 of the fair value hierarchy. Typically, standard inputs such as benchmark yields, reported trades for similar securities, issuer spreads, benchmark securities, bids, offers and reference data including market research publications are used to fair value a security. When these inputs are not available, broker/dealer quotes may be obtained by the vendor to determine the fair value of the security. We review the vendor’s pricing methodologies to determine if observable market information is being used, versus unobservable inputs. Fair value measurements using significant inputs that are unobservable in the market due to limited activity or a less liquid market are classified as Level 3 in the fair value hierarchy. The Company’s Investment Operations Department is responsible for the valuation of Level 3 available-for-sale debt securities. The methodology and variables used as inputs in pricing Level 3 securities are derived from a combination of observable and unobservable inputs. The unobservable inputs are determined through internal assumptions that may vary from period to period due to external factors, such as market movement and credit rating adjustments. At December 31, 2018 , the Company classified $108.9 million of municipal securities as Level 3. These municipal securities are bond issues for various municipal government entities primarily located in the Chicago metropolitan area and southern Wisconsin and are privately placed, non-rated bonds without CUSIP numbers. The Company also classified $3.2 million of U.S. government agencies as Level 3 at December 31, 2018 . The Company’s methodology for pricing these securities focuses on three distinct inputs: equivalent rating, yield and other pricing terms. To determine the rating for a given non-rated municipal bond, the Investment Operations Department references a publicly issued bond by the same issuer if available. A reduction is then applied to the rating obtained from the comparable bond, as the Company believes if liquidated, a non-rated bond would be valued less than a similar bond with a verifiable rating. The reduction applied by the Company is one complete rating grade (i.e. a “AA” rating for a comparable bond would be reduced to “A” for the Company’s valuation). In 2018 , all of the ratings derived in the above process by Investment Operations were “BBB” or better, for both bonds with and without comparable bond proxies. The fair value measurement of municipal bonds is sensitive to the rating input, as a higher rating typically results in an increased valuation. The remaining pricing inputs used in the bond valuation are observable. Based on the rating determined in the above process, Investment Operations obtains a corresponding current market yield curve available to market participants. Other terms including coupon, maturity date, redemption price, number of coupon payments per year, and accrual method are obtained from the individual bond term sheets. Certain municipal bonds held by the Company at December 31, 2018 have a call date that has passed, and are now continuously callable. When valuing these bonds, the fair value is capped at par value as the Company assumes a market participant would not pay more than par for a continuously callable bond. To determine the rating for the U.S. government agency securities, the Investment Operations Department assigned a AAA rating as it is guaranteed by the U.S. government. Mortgage loans held-for-sale —The fair value of mortgage loans held-for-sale is determined by reference to investor price sheets for loan products with similar characteristics. Loans held-for-investment —The fair value for loans in which the Company elected the fair value option is estimated by discounting future scheduled cash flows for the specific loan through maturity, adjusted for estimated credit losses and prepayments. The Company uses a discount rate based on the actual coupon rate of the underlying loan. At December 31, 2018 , the Company classified $11.3 million of loans held-for-investment as Level 3. The weighted average discount rate used as an input to value these loans at December 31, 2018 was 4.31% with discount rates applied ranging from 4% - 5% . The higher the rate utilized to discount estimated future cash flows, the lower the fair value measurement. As noted above, the fair value estimate includes assumptions of prepayment speeds and credit losses. The Company included a prepayments speed assumption of 12.06% at December 31, 2018 . Prepayment speeds are inversely related to the fair value of these loans as an increase in prepayment speeds results in a decreased valuation. Additionally, the weighted average credit discount used as an input to value the specific loans was 1.30% with credit discounts ranging from 0% - 7% at December 31, 2018 . MSRs —Fair value for MSRs is determined utilizing a valuation model which calculates the fair value of each servicing rights based on the present value of estimated future cash flows. The Company uses a discount rate commensurate with the risk associated with each servicing rights, given current market conditions. At December 31, 2018 , the Company classified $75.2 million of MSRs as Level 3. The weighted average discount rate used as an input to value the pool of MSRs at December 31, 2018 was 9.98% with discount rates applied ranging from 6% - 18% . The higher the rate utilized to discount estimated future cash flows, the lower the fair value measurement. The fair value of MSRs was also estimated based on other assumptions including prepayment speeds and the cost to service. Prepayment speeds ranged from 6% - 91% or a weighted average prepayment speed of 11.76% . Further, for current and delinquent loans, the Company assumed the average cost of servicing of $77 and $273 , respectively, per loan. Prepayment speeds and the cost to service are both inversely related to the fair value of MSRs as an increase in prepayment speeds or the cost to service results in a decreased valuation. See Note 6, “Mortgage Servicing Rights (“MSRs”),” for further discussion of MSRs. Derivative instruments —The Company’s derivative instruments include interest rate swaps, caps and collars, commitments to fund mortgages for sale into the secondary market (interest rate locks), forward commitments to end investors for the sale of mortgage loans and foreign currency contracts. Interest rate swaps, caps and collars are valued by a third party, using models that primarily use market observable inputs, such as yield curves, and are validated by comparison with valuations provided by the respective counterparties. The credit risk associated with derivative financial instruments that are subject to master netting agreements is measured on a net basis by counterparty portfolio. The fair value for mortgage-related derivatives is based on changes in mortgage rates from the date of the commitments. The fair value of foreign currency derivatives is computed based on change in foreign currency rates stated in the contract compared to those prevailing at the measurement date. At December 31, 2018 , the Company classified $2.5 million of derivative assets related to interest rate locks as Level 3. The fair value of interest rate locks is based on prices obtained for loans with similar characteristics from third parties, adjusted for the pull-through rate, which represents the Company’s best estimate of the likelihood that a committed loan will ultimately fund. The weighted-average pull-through rate at December 31, 2018 was 86.15% with pull-through rates applied ranging from 17% to 100% . Pull-through rates are directly related to the fair value of interest rate locks as an increase in the pull-through rate results in an increased valuation. Nonqualified deferred compensation assets —The underlying assets relating to the nonqualified deferred compensation plan are included in a trust and primarily consist of non-exchange traded institutional funds which are priced based by an independent third party service.
Fair Value Measurement	The following methods and assumptions were used by the Company in estimating fair values of financial instruments that were not previously disclosed. Held-to-maturity securities. Held-to-maturity securities include U.S. Government-sponsored agency securities and municipal bonds issued by various municipal government entities primarily located in the Chicago metropolitan area and southern Wisconsin. Fair values for held-to-maturity securities are typically based on prices obtained from independent pricing vendors. In accordance with ASC 820, the Company has categorized these held-to-maturity securities as a Level 2 fair value measurement. Fair values for certain other held-to-maturity securities are based on the bond pricing methodology discussed previously related to certain available-for-sale securities. In accordance with ASC 820, the Company has categorized these held-to-maturity securities as a Level 3 fair value measurement. Loans held-for-investment, at amortized cost. Fair values are estimated for portfolios of loans with similar financial characteristics. Loans are analyzed by type such as commercial, residential real estate, etc. Each category is further segmented by interest rate type (fixed and variable) and term. For variable-rate loans that reprice frequently, estimated fair values are based on carrying values. The fair value of residential loans is based on secondary market sources for securities backed by similar loans, adjusted for differences in loan characteristics. The fair value for other fixed rate loans is estimated by discounting scheduled cash flows through the estimated maturity using estimated market discount rates that reflect credit and interest rate risks inherent in the loan. In accordance with ASC 820, the Company has categorized loans as a Level 3 fair value measurement. Deposits with stated maturities. The fair value of certificates of deposit is based on the discounted value of contractual cash flows. The discount rate is estimated using the rates currently in effect for deposits of similar remaining maturities. In accordance with ASC 820, the Company has categorized deposits with stated maturities as a Level 3 fair value measurement. FHLB advances. The fair value of FHLB advances is obtained from the FHLB, which uses a discounted cash flow analysis based on current market rates of similar maturity debt securities to discount cash flows. In accordance with ASC 820, the Company has categorized FHLB advances as a Level 3 fair value measurement. Subordinated notes. The fair value of the subordinated notes is based on a market price obtained from an independent pricing vendor. In accordance with ASC 820, the Company has categorized subordinated notes as a Level 2 fair value measurement. Junior subordinated debentures. The fair value of the junior subordinated debentures is based on the discounted value of contractual cash flows. In accordance with ASC 820, the Company has categorized junior subordinated debentures as a Level 3 fair value measurement. Also, the Company may be required, from time to time, to measure certain other financial assets at fair value on a nonrecurring basis in accordance with GAAP. These adjustments to fair value usually result from impairment charges on individual assets. Impaired loans —A loan is considered to be impaired when, based on current information and events, it is probable that the Company will be unable to collect all amounts due pursuant to the contractual terms of the loan agreement. A loan modified in a TDR is an impaired loan according to applicable accounting guidance. Impairment is measured by estimating the fair value of the loan based on the present value of expected cash flows, the market price of the loan, or the fair value of the underlying collateral. Impaired loans are considered a fair value measurement where an allowance is established based on the fair value of collateral. Appraised values, which may require adjustments to market-based valuation inputs, are generally used on real estate collateral-dependent impaired loans. The Company’s Managed Assets Division is primarily responsible for the valuation of Level 3 inputs of impaired loans. For more information on the Managed Assets Division review of impaired loans refer to Note 5 – Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans. At December 31, 2018 , the Company had $127.3 million of impaired loans classified as Level 3. Of the $127.3 million of impaired loans, $99.8 million were measured at fair value based on the underlying collateral of the loan as shown in the table above. The remaining $27.5 million were valued based on discounted cash flows in accordance with ASC 310. Other real estate owned —Other real estate owned is comprised of real estate acquired in partial or full satisfaction of loans and is included in other assets. Other real estate owned is recorded at its estimated fair value less estimated selling costs at the date of transfer, with any excess of the related loan balance over the fair value less expected selling costs charged to the allowance for loan losses. Subsequent changes in value are reported as adjustments to the carrying amount and are recorded in other non-interest expense. Gains and losses upon sale, if any, are also charged to other non-interest expense. Fair value is generally based on third party appraisals and internal estimates that are adjusted by a discount representing the estimated cost of sale and is therefore considered a Level 3 valuation. The Company’s Managed Assets Division is primarily responsible for the valuation of Level 3 inputs for other real estate owned. At December 31, 2018 , the Company had $24.8 million of other real estate owned classified as Level 3. The unobservable input applied to other real estate owned relates to the 10% reduction to the appraisal value representing the estimated cost of sale of the foreclosed property. A higher discount for the estimated cost of sale results in a decreased carrying value.
Segment Reporting	The Company’s operations consist of three primary segments: community banking, specialty finance and wealth management. The three reportable segments are strategic business units that are separately managed as they offer different products and services and have different marketing strategies. In addition, each segment’s customer base has varying characteristics and each segment has a different regulatory environment. While the Company’s management monitors each of the fifteen bank subsidiaries’ operations and profitability separately, these subsidiaries have been aggregated into one reportable operating segment due to the similarities in products and services, customer base, operations, profitability measures and economic characteristics. For purposes of internal segment profitability, management allocates certain intersegment and parent company balances. Management allocates a portion of revenues to the specialty finance segment related to loans and leases originated by the specialty finance segment and sold or assigned to the community banking segment. Similarly, for purposes of analyzing the contribution from the wealth management segment, management allocates a portion of the net interest income earned by the community banking segment on deposit balances of customers of the wealth management segment to the wealth management segment. See Note 10, “Deposits,” for more information on these deposits. Finally, expenses incurred at the Wintrust parent company are allocated to each segment based on each segment's risk-weighted assets. The segment financial information provided in the following tables has been derived from the internal profitability reporting system used by management to monitor and manage the financial performance of the Company. The accounting policies of the segments are substantially similar to those described in the Summary of Significant Accounting Policies in Note 1. The Company evaluates segment performance based on after-tax profit or loss and other appropriate profitability measures common to each segment.

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Schedule of Investment Securities	A summary of the available-for-sale and held-to-maturity securities portfolios presenting carrying amounts and gross unrealized gains and losses as of December 31, 2018 and 2017 is as follows: December 31, 2018 December 31, 2017 (Dollars in thousands) Amortized Cost Gross unrealized gains Gross unrealized losses Fair Value Amortized Cost Gross unrealized gains Gross unrealized losses Fair Value Available-for-sale securities U.S. Treasury $ 126,199 $ 391 $ (186 ) $ 126,404 $ 144,904 $ — $ (1,082 ) $ 143,822 U.S. Government agencies 139,420 917 (30 ) 140,307 157,638 2 (725 ) 156,915 Municipal 136,831 2,427 (768 ) 138,490 113,197 2,712 (557 ) 115,352 Corporate notes: Financial issuers 97,079 35 (7,069 ) 90,045 30,309 43 (301 ) 30,051 Other 1,000 — — 1,000 1,000 — (1 ) 999 Mortgage-backed: (1) Mortgage-backed securities 1,641,146 2,510 (57,317 ) 1,586,339 1,291,695 446 (31,955 ) 1,260,186 Collateralized mortgage obligations 43,819 500 (823 ) 43,496 60,092 64 (617 ) 59,539 Equity securities (2) — — — — 34,234 3,357 (789 ) 36,802 Total available-for-sale securities $ 2,185,494 $ 6,780 $ (66,193 ) $ 2,126,081 $ 1,833,069 $ 6,624 $ (36,027 ) $ 1,803,666 Held-to-maturity securities U.S. Government agencies $ 814,864 $ 1,141 $ (28,576 ) $ 787,429 $ 579,062 $ 23 $ (14,066 ) $ 565,019 Municipal 252,575 1,100 (5,008 ) 248,667 247,387 2,668 (2,558 ) 247,497 Total held-to-maturity securities $ 1,067,439 $ 2,241 $ (33,584 ) $ 1,036,096 $ 826,449 $ 2,691 $ (16,624 ) $ 812,516 Equity securities with readily determinable fair value (2) $ 34,410 $ 1,532 $ (1,225 ) $ 34,717 $ — $ — $ — $ — (1) Consisting entirely of residential mortgage-backed securities, none of which are subprime. (2) As a result of the adoption of ASU No. 2016-01 effective January 1, 2018, equity securities with readily determinable fair value are no longer presented within available-for-sale securities and are now presented as equity securities with readily determinable fair values in the Company's Consolidated Statements of Condition for the current period.
Schedule of Investment Securities Portfolio Continuous Unrealized Loss Position, Available for Sale Debt Securities	The following table presents the portion of the Company’s available-for-sale and held-to-maturity securities portfolios which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at December 31, 2018 : Continuous unrealized losses existing for less than 12 months Continuous unrealized losses existing for greater than 12 months Total (Dollars in thousands) Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Available-for-sale securities U.S. Treasury $ 5,485 $ (5 ) $ 24,829 $ (181 ) $ 30,314 $ (186 ) U.S. Government agencies — — 11,167 (30 ) 11,167 (30 ) Municipal 10,676 (178 ) 22,147 (590 ) 32,823 (768 ) Corporate notes: Financial issuers 37,076 (2,921 ) 42,934 (4,148 ) 80,010 (7,069 ) Other — — — — — — Mortgage-backed: Mortgage-backed securities 114,958 (124 ) 1,340,916 (57,193 ) 1,455,874 (57,317 ) Collateralized mortgage obligations 510 (1 ) 34,255 (822 ) 34,765 (823 ) Total available-for-sale securities $ 168,705 $ (3,229 ) $ 1,476,248 $ (62,964 ) $ 1,644,953 $ (66,193 ) Held-to-maturity securities U.S. Government agencies $ — $ — $ 601,238 $ (28,576 ) $ 601,238 $ (28,576 ) Municipal 38,239 (637 ) 158,302 (4,371 ) 196,541 (5,008 ) Total held-to-maturity securities $ 38,239 $ (637 ) $ 759,540 $ (32,947 ) $ 797,779 $ (33,584 ) The following table presents the portion of the Company’s available-for-sale and held-to-maturity securities portfolios which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at December 31, 2017 : Continuous unrealized losses existing for less than 12 months Continuous unrealized losses existing for greater than 12 months Total (Dollars in thousands) Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Available-for-sale securities U.S. Treasury $ 24,811 $ (215 ) $ 119,011 $ (867 ) $ 143,822 $ (1,082 ) U.S. Government agencies 14,462 (69 ) 141,471 (656 ) 155,933 (725 ) Municipal 28,221 (256 ) 15,840 (301 ) 44,061 (557 ) Corporate notes: Financial issuers 1,210 (1 ) 5,665 (300 ) 6,875 (301 ) Other — — 999 (1 ) 999 (1 ) Mortgage-backed: Mortgage-backed securities 137,255 (915 ) 989,971 (31,040 ) 1,127,226 (31,955 ) Collateralized mortgage obligations 35,038 (213 ) 13,719 (404 ) 48,757 (617 ) Equity securities 9,116 (343 ) 6,054 (446 ) 15,170 (789 ) Total available-for-sale securities $ 250,113 $ (2,012 ) $ 1,292,730 $ (34,015 ) $ 1,542,843 $ (36,027 ) Held-to-maturity securities U.S. Government agencies $ 241,849 $ (3,263 ) $ 300,200 $ (10,803 ) $ 542,049 $ (14,066 ) Municipal 56,901 (1,004 ) 52,399 (1,554 ) 109,300 (2,558 ) Total held-to-maturity securities $ 298,750 $ (4,267 ) $ 352,599 $ (12,357 ) $ 651,349 $ (16,624 )
Schedule of Investment Securities Portfolio Continuous Unrealized Loss Position, Held to Maturity	The following table presents the portion of the Company’s available-for-sale and held-to-maturity securities portfolios which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at December 31, 2018 : Continuous unrealized losses existing for less than 12 months Continuous unrealized losses existing for greater than 12 months Total (Dollars in thousands) Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Available-for-sale securities U.S. Treasury $ 5,485 $ (5 ) $ 24,829 $ (181 ) $ 30,314 $ (186 ) U.S. Government agencies — — 11,167 (30 ) 11,167 (30 ) Municipal 10,676 (178 ) 22,147 (590 ) 32,823 (768 ) Corporate notes: Financial issuers 37,076 (2,921 ) 42,934 (4,148 ) 80,010 (7,069 ) Other — — — — — — Mortgage-backed: Mortgage-backed securities 114,958 (124 ) 1,340,916 (57,193 ) 1,455,874 (57,317 ) Collateralized mortgage obligations 510 (1 ) 34,255 (822 ) 34,765 (823 ) Total available-for-sale securities $ 168,705 $ (3,229 ) $ 1,476,248 $ (62,964 ) $ 1,644,953 $ (66,193 ) Held-to-maturity securities U.S. Government agencies $ — $ — $ 601,238 $ (28,576 ) $ 601,238 $ (28,576 ) Municipal 38,239 (637 ) 158,302 (4,371 ) 196,541 (5,008 ) Total held-to-maturity securities $ 38,239 $ (637 ) $ 759,540 $ (32,947 ) $ 797,779 $ (33,584 ) The following table presents the portion of the Company’s available-for-sale and held-to-maturity securities portfolios which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at December 31, 2017 : Continuous unrealized losses existing for less than 12 months Continuous unrealized losses existing for greater than 12 months Total (Dollars in thousands) Fair value Unrealized losses Fair value Unrealized losses Fair value Unrealized losses Available-for-sale securities U.S. Treasury $ 24,811 $ (215 ) $ 119,011 $ (867 ) $ 143,822 $ (1,082 ) U.S. Government agencies 14,462 (69 ) 141,471 (656 ) 155,933 (725 ) Municipal 28,221 (256 ) 15,840 (301 ) 44,061 (557 ) Corporate notes: Financial issuers 1,210 (1 ) 5,665 (300 ) 6,875 (301 ) Other — — 999 (1 ) 999 (1 ) Mortgage-backed: Mortgage-backed securities 137,255 (915 ) 989,971 (31,040 ) 1,127,226 (31,955 ) Collateralized mortgage obligations 35,038 (213 ) 13,719 (404 ) 48,757 (617 ) Equity securities 9,116 (343 ) 6,054 (446 ) 15,170 (789 ) Total available-for-sale securities $ 250,113 $ (2,012 ) $ 1,292,730 $ (34,015 ) $ 1,542,843 $ (36,027 ) Held-to-maturity securities U.S. Government agencies $ 241,849 $ (3,263 ) $ 300,200 $ (10,803 ) $ 542,049 $ (14,066 ) Municipal 56,901 (1,004 ) 52,399 (1,554 ) 109,300 (2,558 ) Total held-to-maturity securities $ 298,750 $ (4,267 ) $ 352,599 $ (12,357 ) $ 651,349 $ (16,624 )
Schedule of Gross Gains and Gross Losses Realized and Proceeds For Investment Securities	The following table provides information as to the amount of gross gains and gross losses realized and proceeds received through the sales and calls of investment securities: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Realized gains on investment securities $ 1,144 $ 147 $ 9,399 Realized losses on investment securities (1,111 ) (102 ) (1,754 ) Net realized gains on investment securities 33 $ 45 $ 7,645 Unrealized gains on equity securities with readily determinable fair value 2,771 — — Unrealized losses on equity securities with readily determinable fair value (4,910 ) — — Net unrealized losses on equity securities with readily determinable fair value (2,139 ) — — Upward adjustments of equity securities without readily determinable fair values 325 — — Downward adjustments of equity securities without readily determinable fair values — — — Impairment of equity securities without readily determinable fair values (1,117 ) — — Adjustment and impairment, net, of equity securities without readily determinable fair values (792 ) — — Other than temporary impairment charges — — — (Losses) gains on investment securities, net (2,898 ) 45 7,645 Proceeds from sales of available-for-sale securities 214,196 344,674 2,194,278 Proceeds from sales of equity securities with readily determinable fair value 1,895 — — Proceeds from sales and capital distributions of equity securities without readily determinable fair value 1,324 — —
Contractual Maturities of Investment Securities	The amortized cost and fair value of securities as of December 31, 2018 and December 31, 2017 , by contractual maturity, are shown in the following table. Contractual maturities may differ from actual maturities as borrowers may have the right to call or repay obligations with or without call or prepayment penalties. Mortgage-backed securities are not included in the maturity categories in the following maturity summary as actual maturities may differ from contractual maturities because the underlying mortgages may be called or prepaid without penalties: December 31, 2018 December 31, 2017 (Dollars in thousands) Amortized Cost Fair Value Amortized Cost Fair Value Available-for-sale securities Due in one year or less $ 82,206 $ 82,153 $ 300,833 $ 299,285 Due in one to five years 168,855 169,307 97,019 97,326 Due in five to ten years 121,129 115,206 33,947 35,029 Due after ten years 128,339 129,580 15,249 15,499 Mortgage-backed 1,684,965 1,629,835 1,351,787 1,319,725 Equity securities (1) — — 34,234 36,802 Total available-for-sale securities $ 2,185,494 $ 2,126,081 $ 1,833,069 $ 1,803,666 Held-to-maturity securities Due in one year or less $ 10,009 $ 9,979 $ 170 $ 171 Due in one to five years 29,436 28,995 38,392 38,012 Due in five to ten years 295,897 290,206 205,227 203,680 Due after ten years 732,097 706,916 582,660 570,653 Total held-to-maturity securities $ 1,067,439 $ 1,036,096 $ 826,449 $ 812,516 (1) As a result of the adoption of ASU No. 2016-01 effective January 1, 2018, equity securities with readily determinable fair value are no longer presented within available-for-sale securities and are now presented as equity securities with readily determinable fair values in the Company's Consolidated Statements of Condition for the current period.

Loans (Tables)

Loans (Tables)	12 Months Ended
	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Abstract]
Summary of Loan Portfolio	The following table shows the Company's loan portfolio by category as of the dates shown: (Dollars in thousands) December 31, 2018 December 31, 2017 Balance: Commercial $ 7,828,538 $ 6,787,677 Commercial real estate 6,933,252 6,580,618 Home equity 552,343 663,045 Residential real estate 1,002,464 832,120 Premium finance receivables—commercial 2,841,659 2,634,565 Premium finance receivables—life insurance 4,541,794 4,035,059 Consumer and other 120,641 107,713 Total loans, net of unearned income $ 23,820,691 $ 21,640,797 Mix: Commercial 33 % 31 % Commercial real estate 29 30 Home equity 2 3 Residential real estate 4 4 Premium finance receivables—commercial 12 12 Premium finance receivables—life insurance 19 19 Consumer and other 1 1 Total loans, net of unearned income 100 % 100 %
Unpaid Principal Balance and Carrying Value of Acquired Loans	The following table presents the unpaid principal balance and carrying value for these acquired loans as of the dates shown: December 31, 2018 December 31, 2017 (Dollars in thousands) Unpaid Principal Balance Carrying Value Unpaid Principal Balance Carrying Value PCI loans $ 341,555 $ 318,394 $ 375,237 $ 350,690
Schedule of Loans Acquired with Deteriorated Credit Quality	The following table provides estimated details as of the date of acquisition on loans acquired in 2018 with evidence of credit quality deterioration since origination: (Dollars in thousands) Delaware Place Bank American Enterprise Bank Contractually required payments including interest $ 13,385 $ 31,750 Less: Nonaccretable difference 1,197 3,813 Cash flows expected to be collected (1) $ 12,188 $ 27,937 Less: Accretable yield 2,205 3,970 Fair value of PCI loans acquired $ 9,983 $ 23,967 (1) Represents undiscounted expected principal and interest cash at acquisition.
Activity Related to Accretable Yield of Loans Acquired with Evidence of Credit Quality Deterioration Since Origination	The following table provides activity for the accretable yield of PCI loans. Years Ended December 31, (Dollars in thousands) 2018 2017 Accretable yield, beginning balance $ 36,565 $ 49,408 Acquisitions 6,175 426 Accretable yield amortized to interest income (16,711 ) (21,512 ) Accretable yield amortized to indemnification asset/liability (1) — (1,087 ) Reclassification from non-accretable difference (2) 4,835 7,805 Increases (Decreases) in interest cash flows due to payments and changes in interest rates 4,012 1,525 Accretable yield, ending balance $ 34,876 $ 36,565 (1) Represents the portion of the current period accreted yield, resulting from lower expected losses, applied to reduce the loss share indemnification asset or increase the loss share indemnification liability. (2) Reclassification is the result of subsequent increases in expected principal cash flows.

Allowance for Loan Losses, Al_2

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Tables)	12 Months Ended
	Dec. 31, 2018
Receivables [Abstract]
Schedule of Aging of the Company's Loan Portfolio	The tables below show the aging of the Company’s loan portfolio at December 31, 2018 and 2017 : As of December 31, 2018 (Dollars in thousands) Nonaccrual 90+ days and still accruing 60-89 days past due 30-59 days past due Current Total Loans Loan Balances: Commercial Commercial, industrial and other $ 34,298 $ — $ 1,451 $ 21,618 $ 5,062,729 $ 5,120,096 Franchise 16,051 — — 8,738 924,190 948,979 Mortgage warehouse lines of credit — — — — 144,199 144,199 Asset-based lending 635 — 200 3,156 1,022,065 1,026,056 Leases — — — 1,250 564,430 565,680 PCI - commercial (1) — 3,313 — 99 20,116 23,528 Total commercial $ 50,984 $ 3,313 $ 1,651 $ 34,861 $ 7,737,729 $ 7,828,538 Commercial real estate: Construction 1,554 — — 9,424 749,846 760,824 Land 107 — 170 107 141,097 141,481 Office 3,629 — 877 5,077 929,739 939,322 Industrial 285 — — 16,596 885,367 902,248 Retail 10,753 — 1,890 1,729 878,106 892,478 Multi-family 311 — 77 5,575 970,597 976,560 Mixed use and other 2,490 — 1,617 8,983 2,192,105 2,205,195 PCI - commercial real estate (1) — 6,241 6,195 4,075 98,633 115,144 Total commercial real estate $ 19,129 $ 6,241 $ 10,826 $ 51,566 $ 6,845,490 $ 6,933,252 Home equity 7,147 — 131 3,105 541,960 552,343 Residential real estate, including PCI 16,383 1,292 1,692 6,171 976,926 1,002,464 Premium finance receivables Commercial insurance loans 11,335 7,799 11,382 15,085 2,796,058 2,841,659 Life insurance loans — — 8,407 24,628 4,340,856 4,373,891 PCI - life insurance loans (1) — — — — 167,903 167,903 Consumer and other, including PCI 348 227 87 733 119,246 120,641 Total loans, net of unearned income $ 105,326 $ 18,872 $ 34,176 $ 136,149 $ 23,526,168 $ 23,820,691 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. Loan agings are based upon contractually required payments. See Note 4 , “Loans,” for further discussion of these purchased loans. As of December 31, 2017 (Dollars in thousands) Nonaccrual 90+ days and still accruing 60-89 days past due 30-59 days past due Current Total Loans Loan Balances: Commercial Commercial, industrial and other $ 11,260 $ — $ 3,746 $ 13,392 $ 4,314,107 $ 4,342,505 Franchise 2,447 — — — 845,150 847,597 Mortgage warehouse lines of credit — — — 4,000 190,523 194,523 Asset-based lending 1,550 — 283 10,057 968,576 980,466 Leases 439 — 3 1,958 410,772 413,172 PCI - commercial (1) — 877 186 — 8,351 9,414 Total commercial $ 15,696 $ 877 $ 4,218 $ 29,407 $ 6,737,479 $ 6,787,677 Commercial real estate Construction $ 3,143 $ — $ — $ 200 $ 742,171 $ 745,514 Land 188 — — 5,156 121,140 126,484 Office 2,438 — — 4,458 887,937 894,833 Industrial 811 — — 2,412 879,796 883,019 Retail 12,328 — 668 148 938,383 951,527 Multi-family — — — 1,034 914,610 915,644 Mixed use and other 3,140 — 1,423 9,641 1,921,501 1,935,705 PCI - commercial real estate (1) — 7,135 2,255 6,277 112,225 127,892 Total commercial real estate $ 22,048 $ 7,135 $ 4,346 $ 29,326 $ 6,517,763 $ 6,580,618 Home equity 8,978 — 518 4,634 648,915 663,045 Residential real estate, including PCI 17,977 5,304 1,303 8,378 799,158 832,120 Premium finance receivables Commercial insurance loans 12,163 9,242 17,796 15,849 2,579,515 2,634,565 Life insurance loans — — 4,837 10,017 3,820,936 3,835,790 PCI - life insurance loans (1) — — — — 199,269 199,269 Consumer and other, including PCI 740 101 242 727 105,903 107,713 Total loans, net of unearned income, excluding covered loans 77,602 22,659 33,260 98,338 21,408,938 21,640,797 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. Loan agings are based upon contractually required payments. See Note 4 , “Loans,” for further discussion of these purchased loans.
Summary of Recorded Investment Based on Performance of Loans by Class	The following table presents the recorded investment based on performance of loans by class, per the most recent analysis at December 31, 2018 and 2017 : Performing Non-performing Total December 31, December 31, December 31, December 31, December 31, December 31, (Dollars in thousands) 2018 2017 2018 2017 2018 2017 Loan Balances: Commercial Commercial, industrial and other $ 5,085,798 $ 4,331,245 $ 34,298 $ 11,260 $ 5,120,096 $ 4,342,505 Franchise 932,928 845,150 16,051 2,447 948,979 847,597 Mortgage warehouse lines of credit 144,199 194,523 — — 144,199 194,523 Asset-based lending 1,025,421 978,916 635 1,550 1,026,056 980,466 Leases 565,680 412,733 — 439 565,680 413,172 PCI - commercial (1) 23,528 9,414 — — 23,528 9,414 Total commercial $ 7,777,554 $ 6,771,981 $ 50,984 $ 15,696 $ 7,828,538 $ 6,787,677 Commercial real estate Construction 759,270 742,371 1,554 3,143 760,824 745,514 Land 141,374 126,296 107 188 141,481 126,484 Office 935,693 892,395 3,629 2,438 939,322 894,833 Industrial 901,963 882,208 285 811 902,248 883,019 Retail 881,725 939,199 10,753 12,328 892,478 951,527 Multi-family 976,249 915,644 311 — 976,560 915,644 Mixed use and other 2,202,705 1,932,565 2,490 3,140 2,205,195 1,935,705 PCI - commercial real estate (1) 115,144 127,892 — — 115,144 127,892 Total commercial real estate $ 6,914,123 $ 6,558,570 $ 19,129 $ 22,048 $ 6,933,252 $ 6,580,618 Home equity 545,196 654,067 7,147 8,978 552,343 663,045 Residential real estate, including PCI 986,081 810,865 16,383 21,255 1,002,464 832,120 Premium finance receivables Commercial insurance loans 2,822,525 2,613,160 19,134 21,405 2,841,659 2,634,565 Life insurance loans 4,373,891 3,835,790 — — 4,373,891 3,835,790 PCI - life insurance loans (1) 167,903 199,269 — — 167,903 199,269 Consumer and other, including PCI 120,184 106,933 457 780 120,641 107,713 Total loans, net of unearned income, excluding covered loans $ 23,707,457 $ 21,550,635 $ 113,234 $ 90,162 $ 23,820,691 $ 21,640,797 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 4 , “Loans,” for further discussion of these purchased loans.
Summary of Activity in the Allowance for Credit Losses by Loan Portfolio	A summary of the activity in the allowance for credit losses by loan portfolio (excluding covered loans) for the years ended December 31, 2018 and 2017 is as follows: Year Ended December 31, 2018 (Dollars in thousands) Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans Allowance for credit losses Allowance for loan losses at beginning of period $ 57,811 $ 55,227 $ 10,493 $ 6,688 $ 6,846 $ 840 $ 137,905 Other adjustments (3 ) (85 ) (5 ) (25 ) (63 ) — (181 ) Reclassification to/from allowance for unfunded lending-related commitments — (126 ) — — — — (126 ) Charge-offs (14,532 ) (1,395 ) (2,245 ) (1,355 ) (12,228 ) (880 ) (32,635 ) Recoveries 1,457 5,631 541 2,075 3,069 202 12,975 Provision for credit losses 23,093 1,015 (277 ) (189 ) 10,091 1,099 34,832 Allowance for loan losses at period end $ 67,826 $ 60,267 $ 8,507 $ 7,194 $ 7,715 $ 1,261 $ 152,770 Allowance for unfunded lending-related commitments at period end — 1,394 — — — — 1,394 Allowance for credit losses at period end $ 67,826 $ 61,661 $ 8,507 $ 7,194 $ 7,715 $ 1,261 $ 154,164 By measurement method: Individually evaluated for impairment 6,558 4,287 282 204 — 116 11,447 Collectively evaluated for impairment 60,749 57,329 8,225 6,894 7,715 1,145 142,057 Loans acquired with deteriorated credit quality 519 45 — 96 — — 660 Loans at period end: Individually evaluated for impairment $ 59,529 $ 33,274 $ 12,255 $ 22,064 $ — $ 397 $ 127,519 Collectively evaluated for impairment 7,745,482 6,784,834 540,088 877,526 7,215,550 117,441 23,280,921 Loans acquired with deteriorated credit quality 23,527 115,144 — 9,017 167,903 2,803 318,394 Loan held at fair value — — — 93,857 — — 93,857 Year Ended December 31, 2017 (Dollars in thousands) Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans Allowance for credit losses Allowance for loan losses at beginning of period $ 44,493 $ 51,422 $ 11,774 $ 5,714 $ 7,625 $ 1,263 $ 122,291 Other adjustments (1) 16 (155 ) 167 356 138 51 573 Reclassification to/from allowance for unfunded lending-related commitments 500 (431 ) — — — — 69 Charge-offs (5,159 ) (4,236 ) (3,952 ) (1,284 ) (7,335 ) (729 ) (22,695 ) Recoveries 1,870 2,190 746 452 2,128 299 7,685 Provision for credit losses 16,091 6,437 1,758 1,450 4,290 (44 ) 29,982 Allowance for loan losses at period end $ 57,811 $ 55,227 $ 10,493 $ 6,688 $ 6,846 $ 840 $ 137,905 Allowance for unfunded lending-related commitments at period end — 1,269 — — — — 1,269 Allowance for credit losses at period end $ 57,811 $ 56,496 $ 10,493 $ 6,688 $ 6,846 $ 840 $ 139,174 By measurement method: Individually evaluated for impairment 4,464 2,177 784 586 — 26 8,037 Collectively evaluated for impairment 52,820 53,938 9,709 5,979 6,846 814 130,106 Loans acquired with deteriorated credit quality 527 381 — 123 — — 1,031 Loans at period end: Individually evaluated for impairment $ 35,612 $ 38,534 $ 9,254 $ 21,253 $ — $ 759 $ 105,412 Collectively evaluated for impairment 6,742,651 6,414,192 653,791 765,149 6,470,355 104,840 21,150,978 Loans acquired with deteriorated credit quality 9,414 127,892 — 12,001 199,269 2,114 350,690 Loan held at fair value — — — 33,717 — — 33,717 (1) Includes $742,000 of allowance for covered loan losses reclassified as a result of the termination of all existing loss share agreements with the FDIC during the fourth quarter of 2017.
Summary of Activity in the Allowance for Covered Loan Losses	A summary of activity in the allowance for covered loan losses for the year ended December 31, 2017 is as follows: Year Ended December 31, (Dollars in thousands) 2017 Balance at beginning of period $ 1,322 Allowance for covered loan losses transferred to allowance for loan losses subsequent to loss share termination or expiration (742 ) Provision for covered loan losses before benefit attributable to FDIC loss share agreements (1,063 ) Benefit attributable to FDIC loss share agreements 1,592 Net provision for covered loan losses and transfer from allowance for covered loan losses to allowance for loan losses $ (213 ) Increase in FDIC indemnification liability (1,592 ) Loans charged-off (517 ) Recoveries of loans charged-off 1,000 Net recoveries $ 483 Balance at end of period $ —
Impaired Loans Including Restructured Loans Table	A summary of impaired loans, including TDRs, at December 31, 2018 and 2017 is as follows: (Dollars in thousands) 2018 2017 Impaired loans (included in non-performing and restructured loans): Impaired loans with an allowance for loan loss required (1) $ 60,219 $ 36,084 Impaired loans with no allowance for loan loss required 67,050 69,004 Total impaired loans (2) $ 127,269 $ 105,088 Allowance for loan losses related to impaired loans $ 11,437 $ 8,023 TDRs 66,102 49,786 Reduction of interest income from non-accrual loans 3,422 2,373 Interest income recognized on impaired loans 7,347 6,298 (1) These impaired loans require an allowance for loan losses because the estimated fair value of the loans or related collateral is less than the recorded investment in the loans. (2) Impaired loans are considered by the Company to be non-accrual loans, TDRs or loans with principal and/or interest at risk, even if the loan is current with all payments of principal and interest.
Summary of Impaired Loans Evaluated for Impairment by Loan Class	The following tables present impaired loans evaluated for impairment by loan class as of December 31, 2018 and 2017 : As of For the Year Ended December 31, 2018 (Dollars in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized Impaired loans with a related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 16,703 $ 17,029 $ 4,866 $ 17,868 $ 1,181 Franchise 16,021 16,256 1,375 16,221 909 Asset-based lending 557 557 317 689 50 Leases 1,730 1,730 — 1,812 91 Commercial real estate Construction 1,554 1,554 550 1,554 76 Land — — — — — Office 573 638 21 587 25 Industrial — — — — — Retail 14,633 14,633 3,413 14,694 676 Multi-family — — — — — Mixed use and other 1,188 1,221 293 1,354 66 Home equity 3,133 3,470 282 3,165 131 Residential real estate 4,011 4,263 204 4,056 159 Consumer and other 116 129 116 119 7 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 18,314 $ 21,501 $ — $ 20,547 $ 1,143 Franchise 5,152 5,154 — 5,320 403 Asset-based lending 207 601 — 569 51 Leases 845 879 — 936 56 Commercial real estate Construction 1,117 1,117 — 1,218 52 Land 3,396 3,491 — 3,751 198 Office 3,629 3,642 — 3,651 184 Industrial 322 450 — 363 30 Retail 1,592 1,945 — 1,699 110 Multi-family 1,498 1,595 — 1,529 55 Mixed use and other 3,522 3,836 — 3,611 227 Home equity 9,122 12,383 — 9,323 564 Residential real estate 18,053 20,765 — 18,552 883 Consumer and other 281 407 — 293 20 Total loans, net of unearned income $ 127,269 $ 139,246 $ 11,437 $ 133,481 $ 7,347 As of For the Year Ended December 31, 2017 (Dollars in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized Impaired loans with a related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 6,233 $ 7,323 $ 3,951 $ 7,220 $ 452 Franchise — — — — — Asset-based lending 948 949 355 1,302 72 Leases 2,331 2,337 158 2,463 117 Commercial real estate Construction 3,097 3,897 403 3,690 197 Land — — — — Office 471 471 5 481 24 Industrial 408 408 40 414 25 Retail 15,599 15,657 1,336 15,736 624 Multi-family — — — — — Mixed use and other 1,567 1,586 379 1,599 77 Home equity 1,606 1,869 784 1,626 81 Residential real estate 3,798 3,910 586 3,790 146 Consumer and other 26 28 26 27 2 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial, industrial and other $ 8,460 $ 12,259 $ — $ 10,170 $ 683 Franchise 16,256 16,256 — 17,089 780 Asset-based lending 602 602 — 688 40 Leases 782 782 — 845 49 Commercial real estate Construction 1,367 1,678 — 1,555 84 Land 3,961 4,192 — 4,129 182 Office 2,438 6,140 — 3,484 330 Industrial 403 2,010 — 1,849 174 Retail 2,393 3,538 — 2,486 221 Multi-family 1,231 2,078 — 1,246 76 Mixed use and other 5,275 6,731 — 5,559 351 Home equity 7,648 11,648 — 9,114 603 Residential real estate 17,455 20,327 — 17,926 860 Consumer and other 733 890 — 773 48 Total loans, net of unearned income $ 105,088 $ 127,566 $ 8,023 $ 115,261 $ 6,298
Summary of the Post-Modification Balance of Loans Restructured	The tables below present a summary of the post-modification balance of loans restructured during the years ended December 31, 2018 , 2017 , and 2016 , which represent TDRs: Year ended December 31, 2018 Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 4 $ 13,441 3 $ 691 — $ — 1 $ 12,750 — $ — Franchise 3 5,157 1 35 — — 2 5,122 — — Asset-based lending 1 130 1 130 — — — — — — Leases 1 239 1 239 — — — — — — Commercial real estate Office 1 59 1 59 — — — — — — Industrial — — — — — — — — — — Mixed use and other 2 455 2 455 1 85 — — — — Residential real estate and other 59 9,762 58 9,523 27 2,789 — — 1 239 Total loans 71 $ 29,243 67 $ 11,132 28 $ 2,874 3 $ 17,872 1 $ 239 Year ended December 31, 2017 Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 5 $ 3,775 1 $ 95 1 $ 2,272 3 $ 1,408 — $ — Franchise 3 16,256 — — — — 3 16,256 — — Asset-based lending — — — — — — — — — — Leases — — — — — — — — — — Commercial real estate Office — — — — — — — — — — Industrial — — — — — — — — — — Mixed use and other 1 1,245 1 1,245 — — — — — — Residential real estate and other 12 3,049 10 2,925 8 2,643 1 55 1 69 Total loans 21 $ 24,325 12 $ 4,265 9 $ 4,915 7 $ 17,719 1 $ 69 Year ended December 31, 2016 Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 3 $ 345 3 $ 345 — $ — — $ — 1 $ 275 Franchise — — — — — — — — — — Asset-based lending — — — — — — — — — — Leases 2 2,949 2 2,949 — — — — — — Commercial real estate Office 1 450 1 450 — — — — — — Industrial 6 7,921 6 7,921 3 7,196 — — — — Mixed use and other 2 150 2 150 — — — — — — Residential real estate and other 7 1,082 5 841 6 850 2 470 — — Total loans 21 $ 12,897 19 $ 12,656 9 $ 8,046 2 $ 470 1 $ 275 (1) TDRs may have more than one modification representing a concession. As such, TDRs during the period may be represented in more than one of the categories noted above. (2) Balances represent the recorded investment in the loan at the time of the restructuring.
Troubled Debt Restructuring Subsequent Default	The tables below present a summary of all loans restructured in TDRs during the years ended December 31, 2018 , 2017 , and 2016 , and such loans which were in payment default under the restructured terms during the respective periods: Year Ended December 31, 2018 Year Ended December 31, 2017 Year Ended December 31, 2016 Total (1)(3) Payments in Default (2)(3) Total (1)(3) Payments in Default (2)(3) Total (1)(3) Payments in Default (2)(3) (Dollars in thousands) Count Balance Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial, industrial and other 4 $ 13,441 2 $ 174 5 $ 3,775 4 $ 3,681 3 $ 345 1 $ 28 Franchise 3 5,157 2 5,122 3 16,256 — — — — — — Asset-based lending 1 130 — — — — — — — — — — Leases 1 239 — — — — — — 2 2,949 — — Commercial real-estate Office 1 59 — — — — — — 1 450 1 450 Industrial — — — — — — — — 6 7,921 5 7,347 Mixed use and other 2 455 2 455 1 1,245 1 1,245 2 150 1 16 Residential real estate and other 59 9,762 9 1,957 12 3,049 3 2,052 7 1,082 — — Total loans 71 $ 29,243 15 $ 7,708 21 $ 24,325 8 $ 6,978 21 $ 12,897 8 $ 7,841 (1) Total TDRs represent all loans restructured in TDRs during the year indicated. (2) TDRs considered to be in payment default are over 30 days past-due subsequent to the restructuring. (3) Balances represent the recorded investment in the loan at the time of the restructuring.

Mortgage Servicing Rights (Tabl

Mortgage Servicing Rights (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosures Pertaining to Servicing Assets and Servicing Liabilities [Abstract]
Schedule of Servicing Assets at Fair Value	Following is a summary of the changes in the carrying value of MSRs, accounted for at fair value, for the years ended December 31, 2018 , 2017 and 2016 : December 31, December 31, December 31, (Dollars in thousands) 2018 2017 2016 Balance at beginning of year $ 33,676 $ 19,103 $ 9,092 Additions from loans sold with servicing retained 33,071 18,341 13,091 Additions from acquisitions 13,806 — — Estimate of changes in fair value due to: Payoffs and paydowns (5,039 ) (2,595 ) (2,325 ) Changes in valuation inputs or assumptions (331 ) (1,173 ) (755 ) Fair value at end of year $ 75,183 $ 33,676 $ 19,103 Unpaid principal balance of mortgage loans serviced for others $ 6,545,870 $ 2,929,133 $ 1,784,760

Business Combinations and Ass_2

Business Combinations and Asset Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2018
Business Combinations And Asset Acquisitions [Abstract]
Summary of FDIC Indemnification Asset	The following table summarizes the activity in the Company’s FDIC loss share liability during the periods indicated: Year Ended December 31, (Dollars in thousands) 2017 Balance at beginning of period $ 16,701 Reductions from reimbursable expenses (291 ) Amortization 1,044 Changes in expected reimbursements from the FDIC for changes in expected credit losses (1,658 ) Resolution through payments paid to the FDIC and termination of loss share agreements (15,796 ) Balance at end of period $ —

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill Assets by Business Segment	A summary of the Company’s goodwill assets by business segment is presented in the following table: (Dollars in thousands) January 1, Goodwill Impairment Goodwill Adjustments December 31, 2018 Community banking $ 429,520 $ 35,565 $ — $ — $ 465,085 Specialty finance 40,250 — — (1,907 ) 38,343 Wealth management 32,114 37,599 — — 69,713 Total $ 501,884 $ 73,164 $ — $ (1,907 ) $ 573,141
Summary of Finite-Lived Intangible Assets	A summary of finite-lived intangible assets as of the dates shown and the expected amortization as of December 31, 2018 is as follows: December 31, (Dollars in thousands) 2018 2017 Community banking segment: Core deposit and other intangibles: Gross carrying amount $ 55,366 $ 37,272 Accumulated amortization (29,406 ) (25,427 ) Net carrying amount $ 25,960 $ 11,845 Trademark with indefinite lives: Carrying amount 5,800 — Total net carrying amount $ 31,760 $ 11,845 Specialty finance segment: Customer list intangibles: Gross carrying amount $ 1,958 $ 1,972 Accumulated amortization (1,436 ) (1,298 ) Net carrying amount $ 522 $ 674 Wealth management segment: Customer list and other intangibles: Gross carrying amount $ 20,430 $ 7,940 Accumulated amortization (3,288 ) (2,838 ) Net carrying amount $ 17,142 $ 5,102 Total other intangible assets, net $ 49,424 $ 17,621
Estimated Amortization	Estimated amortization for the year-ended: 2019 $ 11,342 2020 9,582 2021 6,385 2022 4,957 2023 3,621

Premises and Equipment, Net (Ta

Premises and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Summary of Premises and Equipment	A summary of premises and equipment at December 31, 2018 and 2017 is as follows: December 31, (Dollars in thousands) 2018 2017 Land $ 164,232 $ 147,704 Buildings and leasehold improvements 586,968 555,636 Furniture, equipment, and computer software 201,055 203,657 Construction in progress 16,179 6,962 $ 968,434 $ 913,959 Less: Accumulated depreciation and amortization 297,265 292,064 Total premises and equipment, net $ 671,169 $ 621,895

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2018
Deposits [Abstract]
Summary of Deposits	The following is a summary of deposits at December 31, 2018 and 2017 : (Dollars in thousands) 2018 2017 Balance: Non-interest bearing $ 6,569,880 $ 6,792,497 NOW and interest bearing demand deposits 2,897,133 2,315,055 Wealth management deposits 2,996,764 2,323,699 Money market 5,704,866 4,515,353 Savings 2,665,194 2,829,373 Time certificates of deposit 5,260,841 4,407,370 Total deposits $ 26,094,678 $ 23,183,347 Mix: Non-interest bearing 25 % 29 % NOW and interest bearing demand deposits 11 10 Wealth management deposits 12 10 Money market 22 20 Savings 10 12 Time certificates of deposit 20 19 Total deposits 100 % 100 %
Schedule of Maturities of Time Certificates of Deposit	The scheduled maturities of time certificates of deposit at December 31, 2018 and 2017 are as follows: (Dollars in thousands) 2018 2017 Due within one year $ 3,213,010 $ 3,167,220 Due in one to two years 1,251,446 969,130 Due in two to three years 710,836 127,548 Due in three to four years 47,979 98,952 Due in four to five years 37,563 44,206 Due after five years 7 314 Total time certificate of deposits $ 5,260,841 $ 4,407,370
Schedule of Maturities of Time Deposits Over One Hundred Thousand Dollars	The following table sets forth the scheduled maturities of time deposits in denominations of $100,000 or more at December 31, 2018 and 2017 : (Dollars in thousands) 2018 2017 Maturing within three months $ 682,940 $ 695,904 After three but within six months 667,079 614,963 After six but within 12 months 921,547 820,285 After 12 months 1,350,717 784,798 Total $ 3,622,283 $ 2,915,950

Federal Home Loan Bank Advanc_2

Federal Home Loan Bank Advances (Tables)	12 Months Ended
	Dec. 31, 2018
Advances from Federal Home Loan Banks [Abstract]
Summary of Outstanding FHLB Advances	A summary of the outstanding FHLB advances at December 31, 2018 and 2017 , is as follows: (Dollars in thousands) 2018 2017 1.44% advance due January 2018 $ — $ 250,000 1.49% advance due February 2018 — 94,663 1.57% advance due June 2019 1,991 — 1.75% advance due June 2020 3,940 — 1.72% advance due June 2020 2,461 — 1.88% advance due June 2021 2,934 — 4.18% advance due February 2022 25,000 25,000 1.52% advance due March 2022 50,000 50,000 1.45% advance due May 2022 50,000 50,000 1.46% advance due May 2022 90,000 90,000 1.98% advance due January 2023 100,000 — 0.93% advance due January 2028 100,000 — Total FHLB advances $ 426,326 $ 559,663

Other Borrowings (Tables)

Other Borrowings (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Summary Of Other Borrowings	The following is a summary of other borrowings at December 31, 2018 and 2017 : (Dollars in thousands) 2018 2017 Notes payable $ 144,461 $ 41,222 Short-term borrowings 50,593 17,209 Other 47,722 49,131 Secured borrowings 151,079 158,561 Total other borrowings $ 393,855 $ 266,123
Schedule of Financial Instruments Owned and Pledged as Collateral	The following is a summary of these securities pledged as of December 31, 2018 disaggregated by investment category and maturity, and reconciled to the outstanding balance of securities sold under repurchase agreements: (Dollars in thousands) Overnight Sweep Collateral Available-for-sale securities pledged Mortgage-backed securities $ 21,059 Held-to-maturity securities pledged U.S. Government agencies 41,723 Total collateral pledged $ 62,782 Excess collateral 12,189 Securities sold under repurchase agreements $ 50,593

Junior Subordinated Debentures

Junior Subordinated Debentures (Tables)	12 Months Ended
	Dec. 31, 2018
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust [Abstract]
Summary of the Company's Junior Subordinated Debentures	The following table provides a summary of the Company’s junior subordinated debentures as of December 31, 2018 and 2017 . The junior subordinated debentures represent the par value of the obligations owed to the Trusts. Common Securities Trust Preferred Securities Junior Subordinated Debentures Rate Structure Contractual rate at 12/31/2018 Maturity Date Earliest Redemption Date (Dollars in thousands) 2018 2017 Issue Date Wintrust Capital Trust III $ 774 $ 25,000 $ 25,774 $ 25,774 L+3.25 5.69 % 04/2003 04/2033 04/2008 Wintrust Statutory Trust IV 619 20,000 20,619 20,619 L+2.80 5.60 12/2003 12/2033 12/2008 Wintrust Statutory Trust V 1,238 40,000 41,238 41,238 L+2.60 5.40 05/2004 05/2034 06/2009 Wintrust Capital Trust VII 1,550 50,000 51,550 51,550 L+1.95 4.74 12/2004 03/2035 03/2010 Wintrust Capital Trust VIII 1,238 25,000 26,238 26,238 L+1.45 4.25 08/2005 09/2035 09/2010 Wintrust Capital Trust IX 1,547 50,000 51,547 51,547 L+1.63 4.42 09/2006 09/2036 09/2011 Northview Capital Trust I 186 6,000 6,186 6,186 L+3.00 5.54 08/2003 11/2033 08/2008 Town Bankshares Capital Trust I 186 6,000 6,186 6,186 L+3.00 5.54 08/2003 11/2033 08/2008 First Northwest Capital Trust I 155 5,000 5,155 5,155 L+3.00 5.80 05/2004 05/2034 05/2009 Suburban Illinois Capital Trust II 464 15,000 15,464 15,464 L+1.75 4.54 12/2006 12/2036 12/2011 Community Financial Shares Statutory Trust II 109 3,500 3,609 3,609 L+1.62 4.41 06/2007 09/2037 06/2012 Total $ 253,566 $ 253,566 4.94 %

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue by Source	The following table presents revenue from contracts with customers, considered in-scope under ASU 2014-09, disaggregated by the revenue source: (Dollars in thousands) Years Ended Revenue from contracts with customers Location in income statement December 31, December 31, December 31, Brokerage and insurance product commissions Wealth management $ 22,391 $ 22,863 $ 25,519 Trust Wealth management 13,263 12,547 11,993 Asset management Wealth management 55,309 46,356 38,506 Total wealth management 90,963 81,766 76,018 Mortgage broker fees Mortgage banking 1,188 1,565 2,834 Service charges on deposit accounts Service charges on deposit accounts 36,404 34,513 31,210 Administrative services Other non-interest income 4,625 4,165 4,409 Card related fees Other non-interest income 7,441 5,858 5,495 Other deposit related fees Other non-interest income 11,892 11,127 9,555
Contract Assets, Contract Liabilities and Receivables from Contracts with Customers	The following table provides information about contract assets, contract liabilities and receivables from contracts with customers: (Dollars in thousands) December 31, December 31, Contract assets $ — $ — Contract liabilities $ 1,727 $ 1,706 Mortgage broker fees receivable $ 44 $ 69 Administrative services receivable 275 — Wealth management receivable 13,610 8,102 Card related fees receivable — 202 Total receivables from contracts with customer $ 13,929 $ 8,373
Performance Obligations Unsatisfied at End of Period	For contracts with an original expected length of more than one year, the following table presents the estimated future timing of recognition of upfront fees related to card and deposit related fees. These upfront fees represent performance obligations that are unsatisfied or partially unsatisfied at the end of the reporting period. (Dollars in thousands) Estimated—2019 $ 759 Estimated—2020 369 Estimated—2021 303 Estimated—2022 153 Estimated—2023 143 Total $ 1,727

Minimum Lease Commitments (Tabl

Minimum Lease Commitments (Tables)	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Approximate Minimum Annual Gross Rental Payments and Gross Rental Income	The approximate minimum annual gross rental payments and gross rental receipts under noncancelable agreements for office space with remaining terms in excess of one year as of December 31, 2018 , are as follows (in thousands): Payments Receipts 2019 $ 15,106 $ 7,533 2020 16,406 5,576 2021 15,116 5,081 2022 14,253 3,636 2023 13,201 2,117 2024 and thereafter 131,615 5,233 Total minimum future amounts $ 205,697 $ 29,176

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit)	Income tax expense (benefit) for the years ended December 31, 2018 , 2017 and 2016 is summarized as follows: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Current income taxes: Federal $ 44,266 $ 54,977 $ 98,272 State 18,349 12,852 20,041 Foreign (872 ) 1,243 (10 ) Total current income taxes $ 61,743 $ 69,072 $ 118,303 Deferred income taxes: Federal $ 40,500 $ 51,668 $ 4,464 State 11,705 10,403 (14 ) Foreign 3,019 1,172 2,226 Total deferred income taxes $ 55,224 $ 63,243 $ 6,676 Total income tax expense $ 116,967 $ 132,315 $ 124,979
Reconciliation of the Differences Between Taxes Computed Using the Statutory Federal Income Tax Rate and Actual Income Tax Expense	A reconciliation of the differences between taxes computed using the statutory Federal income tax rate and actual income tax expense is as follows: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Income tax expense using the statutory Federal income tax rate of 21% in 2018, and 35% in 2017 and 2016, on income before income taxes $ 96,628 $ 136,499 $ 116,149 Increase (decrease) in tax resulting from: Tax-exempt interest, net of interest expense disallowance (3,869 ) (4,658 ) (3,634 ) State taxes, net of federal tax benefit 23,584 15,115 13,017 Income earned on bank owned life insurance (1,002 ) (1,167 ) (1,198 ) Excess tax benefits on share based compensation (3,107 ) (5,470 ) — Enactment of Tax Cuts and Jobs Act Re-measurement of net deferred tax liabilities (1,209 ) (10,402 ) — Transition tax on deferred foreign earnings — 2,850 — Meals, entertainment and related expenses 1,840 1,710 1,439 FDIC insurance expense 1,832 — — Non-deductible compensation expense 1,366 55 77 Foreign subsidiary, net 1,591 (271 ) (264 ) Tax benefits related to tax credit investments, net (656 ) (698 ) (572 ) Other, net (31 ) (1,248 ) (35 ) Income tax expense $ 116,967 $ 132,315 $ 124,979
Deferred Tax Assets and Liabilities	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and liabilities at December 31, 2018 and 2017 are as follows: (Dollars in thousands) 2018 2017 Deferred tax assets: Allowance for credit losses $ 40,342 $ 36,442 Deferred compensation 22,363 12,310 Net unrealized losses on securities included in other comprehensive income 15,430 7,465 Stock-based compensation 7,544 6,898 Federal net operating loss carryforward 5,348 3,063 Loans 4,540 4,943 Other real estate owned 2,429 4,019 AMT credit carryforward 1,395 1,199 Nonaccrued interest 1,357 983 Mortgage banking recourse obligation 632 722 Other 3,744 2,307 Total gross deferred tax assets 105,124 80,351 Deferred tax liabilities: Equipment leasing 90,306 42,681 Premises and equipment 28,517 23,211 Capitalized servicing rights 16,663 8,916 Goodwill and intangible assets 12,921 7,619 Deferred loan fees and costs 3,446 3,531 Net unrealized gains on derivatives included in other comprehensive income 2,863 3,197 Fair value adjustments on loans 2,833 3,143 Other 5,295 3,433 Total gross deferred liabilities 162,844 95,731 Net deferred tax liabilities $ (57,720 ) $ (15,380 )
Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible	The Company accounts for uncertainties in income taxes in accordance with ASC 740, Income Taxes. The following table provides a reconciliation of the beginning and ending amounts of gross unrecognized tax benefits: Years Ended December 31, (Dollars in thousands) 2018 2017 2016 Unrecognized tax benefits at beginning of year $ 10,821 $ 11,626 $ — Gross increases for tax positions taken in current period — — — Gross increases (decreases) for positions taken in prior periods 717 (805 ) 11,626 Unrecognized tax benefits at end of the year $ 11,538 $ 10,821 $ 11,626

Stock Compensation Plans and _2

Stock Compensation Plans and Other Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2018
Share-based Compensation [Abstract]
Weighted Average Assumptions Used to Determine the Options Fair Value	The following table presents the weighted average assumptions used to determine the fair value of options granted in the year ended December 31, 2016 . No options were granted in the years ended December 31, 2018 and 2017. 2016 Expected dividend yield 0.9 % Expected volatility 25.2 % Risk-free rate 1.3 % Expected option life (in years) 4.5
Summary of Stock Option Activity	A summary of the Plans’ stock option activity for the years ended December 31, 2018 , 2017 and 2016 is as follows: Stock Options Common Shares Weighted Average Strike Price Remaining Contractual Term (1) Intrinsic Value (2) ($000) Outstanding at January 1, 2016 1,551,734 $ 41.32 Granted 562,166 41.04 Exercised (313,900 ) 37.71 Forfeited or canceled (101,088 ) 48.00 Outstanding at December 31, 2016 1,698,912 $ 41.50 4.6 $ 52,790 Exercisable at December 31, 2016 703,892 $ 39.62 3.4 $ 23,195 Outstanding at January 1, 2017 1,698,912 $ 41.50 Granted — — Exercised (593,459 ) 40.57 Forfeited or canceled (20,697 ) 42.83 Outstanding at December 31, 2017 1,084,756 $ 41.98 4.0 $ 43,817 Exercisable at December 31, 2017 562,810 $ 41.82 3.3 $ 22,820 Outstanding at January 1, 2018 1,084,756 $ 41.98 Granted — — Exercised (282,614 ) 41.25 Forfeited or canceled (7,128 ) 39.84 Outstanding at December 31, 2018 795,014 $ 42.25 3.1 $ 19,268 Exercisable at December 31, 2018 613,932 $ 42.54 3.1 $ 14,705 Vested or expected to vest at December 31, 2018 787,753 $ 42.26 3.1 $ 19,085 (1) Represents the weighted average contractual remaining life in years. (2) Aggregate intrinsic value represents the total pretax intrinsic value (i.e., the difference between the Company’s stock price at year end and the option exercise price, multiplied by the number of shares) that would have been received by the option holders if they had exercised their options on the last day of the year. Options with exercise prices above the year end stock price are excluded from the calculation of intrinsic value. The intrinsic value will change based on the fair market value of the Company’s stock.
Summary of Plans' Restricted Share Award Activity	A summary of the Plans’ restricted share activity for the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 2017 2016 Restricted Shares Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Outstanding at January 1 127,787 $ 53.33 133,425 $ 49.94 137,593 $ 49.63 Granted 35,654 84.36 16,552 73.16 18,022 46.01 Vested and issued (18,324 ) 54.31 (19,639 ) 47.13 (20,007 ) 44.91 Forfeited (1,854 ) 63.50 (2,551 ) 52.26 (2,183 ) 44.18 Outstanding at end of year 143,263 $ 60.80 127,787 $ 53.33 133,425 $ 49.94 Vested, but not issuable at end of year 90,520 $ 51.94 89,723 $ 51.64 89,050 $ 51.47 A summary of the 2007 Plan’s performance-based stock award activity, based on the target level of the awards, for the years ended December 31, 2018 , 2017 and 2016 is as follows: 2018 2017 2016 Performance Shares Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Outstanding at January 1 359,196 $ 54.37 298,180 $ 43.64 276,533 $ 43.01 Granted 134,380 88.27 145,853 72.60 118,084 41.02 Vested and issued (82,307 ) 44.39 (68,712 ) 46.85 (78,410 ) 37.90 Expired, canceled or forfeited (14,414 ) 60.05 (16,125 ) 52.98 (18,027 ) 41.83 Outstanding at end of year 396,855 $ 67.71 359,196 $ 54.37 298,180 $ 43.64 Vested, but deferred at year end 21,530 $ 43.54 108,143 $ 44.16 6,672 $ 37.98

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2018
Regulatory Capital Requirements [Abstract]
Schedule of Compliance with Minimum Capital Requirements	As reflected in the following table, the Company met all minimum capital requirements at December 31, 2018 and 2017 : 2018 2017 Total capital to risk weighted assets 11.6 % 12.0 % Tier 1 capital to risk weighted assets 9.7 9.9 Common Equity Tier 1 capital to risk weighted assets 9.3 9.4 Tier 1 leverage Ratio 9.1 9.3
Actual Capital Amounts And Ratios	The banks’ actual capital amounts and ratios as of December 31, 2018 and 2017 are presented in the following table: (Dollars in thousands) December 31, 2018 December 31, 2017 Actual To Be Well Capitalized by Regulatory Definition Actual To Be Well Capitalized by Regulatory Definition Amount Ratio Amount Ratio Amount Ratio Amount Ratio Total Capital (to Risk Weighted Assets): Lake Forest Bank $ 424,872 12.5 % $ 338,823 10.0 % $ 366,407 11.6 % $ 317,180 10.0 % Hinsdale Bank 256,166 11.9 220,004 10.0 224,577 11.5 195,125 10.0 Wintrust Bank 613,037 11.5 533,154 10.0 512,581 11.2 456,230 10.0 Libertyville Bank 161,453 11.9 135,262 10.0 141,723 11.4 124,637 10.0 Barrington Bank 258,301 11.1 231,871 10.0 234,930 12.0 195,409 10.0 Crystal Lake Bank 107,041 11.6 92,542 10.0 95,532 11.3 84,664 10.0 Northbrook Bank 236,201 11.1 213,524 10.0 222,441 11.4 194,764 10.0 Schaumburg Bank 113,797 11.4 100,151 10.0 111,772 11.9 93,752 10.0 Village Bank 151,653 11.2 135,695 10.0 145,517 11.9 121,867 10.0 Beverly Bank 146,054 11.8 123,618 10.0 132,516 11.7 112,810 10.0 Town Bank 208,479 11.3 184,825 10.0 188,987 11.4 166,253 10.0 Wheaton Bank 165,798 11.3 147,354 10.0 151,141 11.4 132,211 10.0 State Bank of the Lakes 111,530 11.1 100,654 10.0 105,770 11.4 92,518 10.0 Old Plank Trail Bank 151,889 11.4 132,842 10.0 145,272 11.6 125,642 10.0 St. Charles Bank 115,607 11.4 101,337 10.0 105,778 11.4 92,582 10.0 Tier 1 Capital (to Risk Weighted Assets): Lake Forest Bank $ 402,156 11.9 % $ 271,058 8.0 % $ 347,924 11.0 % $ 253,744 8.0 % Hinsdale Bank 244,036 11.3 176,003 8.0 214,061 11.0 156,100 8.0 Wintrust Bank 545,649 10.2 426,523 8.0 439,061 9.6 364,984 8.0 Libertyville Bank 152,939 11.3 108,209 8.0 134,310 10.8 99,709 8.0 Barrington Bank 252,189 10.9 185,497 8.0 229,311 11.7 156,327 8.0 Crystal Lake Bank 102,404 11.1 74,033 8.0 91,273 10.8 67,731 8.0 Northbrook Bank 223,849 10.5 170,819 8.0 198,628 10.2 155,811 8.0 Schaumburg Bank 108,338 10.8 80,120 8.0 105,733 11.3 75,001 8.0 Village Bank 142,333 10.5 108,556 8.0 136,807 11.2 97,494 8.0 Beverly Bank 141,140 11.4 98,894 8.0 127,561 11.3 90,248 8.0 Town Bank 199,982 10.8 147,860 8.0 180,943 10.9 133,003 8.0 Wheaton Bank 159,718 10.8 117,883 8.0 135,009 10.2 105,769 8.0 State Bank of the Lakes 107,234 10.7 80,523 8.0 95,520 10.3 74,014 8.0 Old Plank Trail Bank 145,779 11.0 106,273 8.0 139,366 11.1 100,514 8.0 St. Charles Bank 111,454 11.0 81,069 8.0 102,251 11.0 74,066 8.0 Common Equity Tier 1 Capital (to Risk Weighted Assets): Lake Forest Bank $ 402,156 11.9 % $ 220,235 6.5 % $ 347,924 11.0 % $ 206,167 6.5 % Hinsdale Bank 244,036 11.3 143,002 6.5 214,061 11.0 126,831 6.5 Wintrust Bank 545,649 10.2 346,550 6.5 439,061 9.6 296,549 6.5 Libertyville Bank 152,939 11.3 87,920 6.5 134,310 10.8 81,014 6.5 Barrington Bank 252,189 10.9 150,716 6.5 229,311 11.7 127,016 6.5 Crystal Lake Bank 102,404 11.1 60,152 6.5 91,273 10.8 55,031 6.5 Northbrook Bank 223,849 10.5 138,791 6.5 198,628 10.2 126,597 6.5 Schaumburg Bank 108,338 10.8 65,098 6.5 105,733 11.3 60,939 6.5 Village Bank 142,333 10.5 88,201 6.5 136,807 11.2 79,214 6.5 Beverly Bank 141,140 11.4 80,352 6.5 127,561 11.3 73,327 6.5 Town Bank 199,982 10.8 120,136 6.5 180,943 10.9 108,065 6.5 Wheaton Bank 159,718 10.8 95,780 6.5 135,009 10.2 85,937 6.5 State Bank of the Lakes 107,234 10.7 65,425 6.5 95,520 10.3 60,137 6.5 Old Plank Trail Bank 145,779 11.0 86,347 6.5 139,366 11.1 81,667 6.5 St. Charles Bank 111,454 11.0 65,869 6.5 102,251 11.0 60,178 6.5 (Dollars in thousands) December 31, 2018 December 31, 2017 Actual To Be Well Capitalized by Regulatory Definition Actual To Be Well Capitalized by Regulatory Definition Amount Ratio Amount Ratio Amount Ratio Amount Ratio Tier 1 Leverage Ratio: Lake Forest Bank $ 402,156 10.7 % $ 187,634 5.0 % $ 347,924 10.3 % $ 168,865 5.0 % Hinsdale Bank 244,036 10.4 117,308 5.0 214,061 10.2 105,086 5.0 Wintrust Bank 545,649 9.7 281,090 5.0 439,061 9.2 237,782 5.0 Libertyville Bank 152,939 10.0 76,247 5.0 134,310 9.8 68,404 5.0 Barrington Bank 252,189 12.9 97,759 5.0 229,311 11.8 97,007 5.0 Crystal Lake Bank 102,404 9.9 51,974 5.0 91,273 9.5 48,069 5.0 Northbrook Bank 223,849 9.8 114,125 5.0 198,628 9.5 104,377 5.0 Schaumburg Bank 108,338 9.5 57,111 5.0 105,733 10.1 52,171 5.0 Village Bank 142,333 9.5 75,197 5.0 136,807 9.7 70,182 5.0 Beverly Bank 141,140 10.7 66,109 5.0 127,561 10.8 59,140 5.0 Town Bank 199,982 10.0 100,257 5.0 180,943 10.1 89,617 5.0 Wheaton Bank 159,718 9.8 81,767 5.0 135,009 9.4 72,152 5.0 State Bank of the Lakes 107,234 9.2 58,068 5.0 95,520 9.2 51,681 5.0 Old Plank Trail Bank 145,779 9.6 76,096 5.0 139,366 9.9 70,735 5.0 St. Charles Bank 111,454 9.8 56,915 5.0 102,251 9.8 51,907 5.0

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Fair Value of Derivative Financial Instruments	The table below presents the fair value of the Company’s derivative financial instruments as of December 31, 2018 and December 31, 2017 : Derivative Assets Derivative Liabilities Fair Value Fair Value (Dollars in thousands) December 31, 2018 December 31, 2017 December 31, 2018 December 31, 2017 Derivatives designated as hedging instruments under ASC 815: Interest rate derivatives designated as Cash Flow Hedges $ 6,270 $ 11,914 $ 1,656 $ 12 Interest rate derivatives designated as Fair Value Hedges 2,636 2,932 1,756 — Total derivatives designated as hedging instruments under ASC 815 $ 8,906 $ 14,846 $ 3,412 $ 12 Derivatives not designated as hedging instruments under ASC 815: Interest rate derivatives $ 59,519 $ 34,139 $ 59,159 $ 33,704 Interest rate lock commitments 3,405 2,843 2,694 269 Forward commitments to sell mortgage loans — 14 1,486 1,457 Foreign exchange contracts 1,342 227 1,337 229 Total derivatives not designated as hedging instruments under ASC 815 $ 64,266 $ 37,223 $ 64,676 $ 35,659 Total Derivatives $ 73,172 $ 52,069 $ 68,088 $ 35,671
Schedule of Cash Flow Hedging Instruments	The table below provides details on each of these cash flow hedges as of December 31, 2018 : (Dollars in thousands) December 31, 2018 Maturity Date Notional Amount Fair Value Asset (Liability) Interest Rate Swaps: June 2019 $ 200,000 $ 957 July 2019 250,000 2,196 August 2019 275,000 3,117 Interest Rate Collars: September 2023 144,643 (1,656 ) Total Cash Flow Hedges $ 869,643 $ 4,614
Rollforward of Amounts in Accumulated Other Comprehensive Income Related to Interest Rate Swaps Designated as Cash Flow Hedges	A rollforward of the amounts in accumulated other comprehensive gain related to interest rate derivatives designated as cash flow hedges follows: Years Ended December 31, (Dollars in thousands) 2018 2017 Unrealized gain at beginning of period $ 11,902 $ 6,944 Amount reclassified from accumulated other comprehensive income to interest expense on deposits and junior subordinated debentures (7,313 ) (19 ) Amount of gain recognized in other comprehensive income 6,153 4,977 Unrealized gain at end of period $ 10,742 $ 11,902
Schedule of Derivatives in Fair Value Hedging Relationships	The following table presents the carrying amount of the hedged assets/(liabilities) and the cumulative amount of fair value hedging adjustment included in the carrying amount of the hedged assets/(liabilities) that are designated as a fair value hedge accounting relationship as of December 31, 2018: December 31, 2018 (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location in the Statement of Condition Carrying Amount of the Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities) Cumulative Amount of Fair Value Hedging Adjustment Remaining for any Hedged Assets (Liabilities) for which Hedge Accounting has been Discontinued Interest rate swaps Loans, net of unearned income, excluding covered loans $ 135,944 $ (953 ) $ — Available-for-sale debt securities 1,497 58 — The following table presents the loss or gain recognized related to derivative instruments that are designated as fair value hedges for the respective periods: (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location of Gain or (Loss) Recognized in Income on Derivative Year Ended December 31, 2018 Interest rate swaps Interest and fees on loans $ (131 ) Interest income - investment securities —
Summary Amounts Included in Consolidated Statement of Income Related to Derivatives	Amounts included in the Consolidated Statements of Income related to derivative instruments not designated in hedge relationships were as follows: (Dollars in thousands) December 31, Derivative Location in income statement 2018 2017 Interest rate swaps and caps Trading gains (losses), net $ (75 ) $ (848 ) Mortgage banking derivatives Mortgage banking revenue (792 ) 1,314 Covered call options Fees from covered call options 3,519 4,402 Foreign exchange contracts Trading gains (losses), net 20 (38 )
Summary of Interest Rate Derivatives	The tables below summarize the Company's interest rate derivatives and offsetting positions as of the dates shown. Derivative Assets Derivative Liabilities Fair Value Fair Value (Dollars in thousands) December 31, 2018 December 31, 2017 December 31, December 31, Gross Amounts Recognized $ 68,425 $ 48,985 $ 62,571 $ 33,716 Less: Amounts offset in the Statements of Condition — — — — Net amount presented in the Statements of Condition $ 68,425 $ 48,985 $ 62,571 $ 33,716 Gross amounts not offset in the Statements of Condition Offsetting Derivative Positions $ (28,124 ) $ (14,878 ) $ (28,124 ) $ (14,878 ) Collateral Posted (23,810 ) (18,060 ) (2,640 ) (2,220 ) Net Credit Exposure $ 16,491 $ 16,047 $ 31,807 $ 16,618

Fair Value of Assets and Liab_2

Fair Value of Assets and Liabilities (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Summary of Balances of Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables present the balances of assets and liabilities measured at fair value on a recurring basis for the periods presented: December 31, 2018 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 126,404 $ 126,404 $ — $ — U.S. Government agencies 140,307 — 137,157 3,150 Municipal 138,490 — 29,564 108,926 Corporate notes 91,045 — 91,045 — Mortgage-backed 1,629,835 — 1,629,835 — Trading account securities 1,692 — 1,692 — Equity securities with readily determinable fair value 34,717 — 34,717 — Mortgage loans held-for-sale 264,070 — 264,070 — Loans held-for-investment 93,857 — 82,510 11,347 MSRs 75,183 — — 75,183 Nonqualified deferred compensations assets 11,282 — 11,282 — Derivative assets 73,172 — 70,715 2,457 Total $ 2,680,054 $ 126,404 $ 2,352,587 $ 201,063 Derivative liabilities $ 68,088 $ — $ 68,088 $ — December 31, 2017 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 143,822 $ 143,822 $ — $ — U.S. Government agencies 156,915 — 153,136 3,779 Municipal 115,352 — 38,171 77,181 Corporate notes 31,050 — 31,050 — Mortgage-backed 1,319,725 — 1,319,725 — Equity securities 36,802 — 36,802 — Trading account securities 995 — 995 — Mortgage loans held-for-sale 313,592 — 313,592 — Loans held-for-investment 33,717 — — 33,717 MSRs 33,676 — — 33,676 Nonqualified deferred compensations assets 11,065 — 11,065 — Derivative assets 52,069 — 49,912 2,157 Total $ 2,248,780 $ 143,822 $ 1,954,448 $ 150,510 Derivative liabilities $ 35,671 $ — $ 35,671 $ —
Summary of Changes in Level Three Assets and Liabilities Measured at Fair Value on a Recurring Basis	The changes in Level 3 assets measured at fair value on a recurring basis during the year ended December 31, 2018 are summarized as follows: U.S. Government Agencies Loans held-for-investment MSRs Derivative assets (Dollars in thousands) Municipal Balance at January 1, 2018 $ 77,181 $ 3,779 $ 33,717 $ 33,676 $ 2,157 Total net gains (losses) included in: Net income (1) — — (1,077 ) 27,701 300 Other comprehensive loss (8,541 ) (314 ) — — — Purchases (2) 63,644 — — 13,806 — Issuances — — — — — Sales — — — — — Settlements (23,358 ) (315 ) (28,367 ) — — Net transfers into/(out of) Level 3 — — 7,074 — — Balance at December 31, 2018 $ 108,926 $ 3,150 $ 11,347 $ 75,183 $ 2,457 (1) Changes in the balance of MSRs and derivative assets as presented in the table above are recorded as a component of mortgage banking revenue in non-interest income. Changes in the balance of loans held-for-investment related to fair value adjustments are recorded as other non-interest income. (2) Purchased as a part of the Veterans First business combination. See Note 7 - Business Combinations and Asset Acquisitions for further discussion. The changes in Level 3 assets measured at fair value on a recurring basis during the year ended December 31, 2017 are summarized as follows: (Dollars in thousands) Municipal U.S. Government Agencies Loans held-for-investment MSRs Derivative assets Balance at January 1, 2017 $ 79,626 $ — $ 22,137 $ 19,103 $ 2,291 Total net gains (losses) included in: Net income (1) — — 1,025 14,573 (134 ) Other comprehensive loss (501 ) (504 ) — — — Purchases 33,593 — — — — Issuances — — — — — Sales — — — — — Settlements (35,537 ) — (13,219 ) — — Net transfers into/(out of) Level 3 (2) — 4,283 23,774 — — Balance at December 31, 2017 $ 77,181 $ 3,779 $ 33,717 $ 33,676 $ 2,157 (1) Changes in the balance of MSRs and derivative assets as presented in the table above are recorded as a component of mortgage banking revenue in non-interest income. Changes in the balance of loans held-for-investment related to fair value adjustments are recorded as other non-interest income. (2) Transfers into Level 3 relate to certain U.S. government agency available-for-sale investment securities and loans reclassified from the held-for-sale portfolio at the time of market conditions or other developments changing management's intent with respect to the disposition of those loans.
Summary of Assets Measured at Fair Value on a Nonrecurring Basis	For assets measured at fair value on a nonrecurring basis that were still held in the balance sheet at the end of the period, the following table provides the carrying value of the related individual assets or portfolios at December 31, 2018 . December 31, 2018 Year Ended December 31, 2018 Fair Value Losses Recognized, net (Dollars in thousands) Total Level 1 Level 2 Level 3 Impaired loans-collateral based $ 99,803 $ — $ — $ 99,803 $ 18,721 Other real estate owned (1) 24,820 — — 24,820 5,965 Total $ 124,623 $ — $ — $ 124,623 $ 24,686 (1) Fair value losses recognized, net on other real estate owned include valuation adjustments and charge-offs during the respective period.
Schedule of Valuation Techniques and Significant Unobservable Inputs Used to Measure Both Recurring and Nonrecurring	The valuation techniques and significant unobservable inputs used to measure both recurring and non-recurring Level 3 fair value measurements at December 31, 2018 were as follows: (Dollars in thousands) Fair Value Valuation Methodology Significant Unobservable Input Range of Inputs Weighted Average of Inputs Impact to valuation from an increased or higher input value Measured at fair value on a recurring basis: Municipal securities $ 108,926 Bond pricing Equivalent rating BBB-AA+ N/A Increase U.S. Government agencies 3,150 Bond pricing Equivalent rating AAA AAA Increase Loans held-for-investment 11,347 Discounted cash flows Discount rate 4%-5% 4.31% Decrease Credit spread 0%-7% 1.30% Decrease Constant prepayment rate (CPR) 12.06% 12.06% Decrease MSRs 75,183 Discounted cash flows Discount rate 6%-18% 9.98% Decrease Constant prepayment rate (CPR) 6%-91% 11.76% Decrease Cost of servicing $15-$200 $ 77 Decrease Cost of servicing - delinquent $200-$1,000 $ 273 Decrease Derivatives 2,457 Discounted cash flows Pull-through rate 17%-100% 86.15 % Increase Measured at fair value on a non-recurring basis: Impaired loans—collateral based 99,803 Appraisal value Appraisal adjustment - cost of sale 10% 10.00% Decrease Other real estate owned, including covered other real-estate owned 24,820 Appraisal value Appraisal adjustment - cost of sale 10% 10.00% Decrease
Summary of Carrying Amounts and Estimated Fair Values of Financial Instruments	The table below presents the carrying amounts and estimated fair values of the Company’s financial instruments as of the dates shown: December 31, 2018 December 31, 2017 (Dollars in thousands) Carrying Value Fair Value Carrying Value Fair Value Financial Assets: Cash and cash equivalents $ 392,200 $ 392,200 $ 277,591 $ 277,591 Interest bearing deposits with banks 1,099,594 1,099,594 1,063,242 1,063,242 Available-for-sale securities 2,126,081 2,126,081 1,803,666 1,803,666 Held-to-maturity securities 1,067,439 1,036,096 826,449 812,516 Trading account securities 1,692 1,692 995 995 Equity securities with readily determinable fair value 34,717 34,717 — — FHLB and FRB stock, at cost 91,354 91,354 89,989 89,989 Brokerage customer receivables 12,609 12,609 26,431 26,431 Mortgage loans held-for-sale, at fair value 264,070 264,070 313,592 313,592 Loans held-for-investment, at fair value 93,857 93,857 33,717 33,717 Loans held-for-investment, at amortized cost 23,726,834 23,780,739 21,607,080 21,768,978 MSRs 75,183 75,183 33,676 33,676 Nonqualified deferred compensation assets 11,282 11,282 11,065 11,065 Derivative assets 73,172 73,172 52,069 52,069 Accrued interest receivable and other 260,281 260,281 227,649 227,649 Total financial assets $ 29,330,365 $ 29,352,927 $ 26,367,211 $ 26,515,176 Financial Liabilities Non-maturity deposits $ 20,833,837 $ 20,833,837 $ 18,775,977 $ 18,775,977 Deposits with stated maturities 5,260,841 5,283,063 4,407,370 4,350,004 FHLB advances 426,326 429,830 559,663 544,750 Other borrowings 393,855 393,855 266,123 266,123 Subordinated notes 139,210 138,345 139,088 144,266 Junior subordinated debentures 253,566 263,846 253,566 264,696 Derivative liabilities 68,088 68,088 35,671 35,671 Accrued interest payable 16,025 16,025 8,030 8,030 Total financial liabilities $ 27,391,748 $ 27,426,889 $ 24,445,488 $ 24,389,517

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2018
Stockholders' Equity Note [Abstract]
Summary of the Company's Common and Preferred Stock	A summary of the Company’s common and preferred stock at December 31, 2018 and 2017 is as follows: 2018 2017 Common Stock: Shares authorized 100,000,000 100,000,000 Shares issued 56,518,119 56,068,220 Shares outstanding 56,407,558 55,965,207 Cash dividend per share $ 0.76 $ 0.56 Preferred Stock: Shares authorized 20,000,000 20,000,000 Shares issued 5,000,000 5,000,000 Shares outstanding 5,000,000 5,000,000
Components of Other Comprehensive Income (Loss), Including the Related Income Tax Effects	The following tables summarize the components of other comprehensive income (loss), including the related income tax effects, for the years ended December 31, 2018 , 2017 and 2016 : (In thousands) Accumulated Unrealized Losses on Securities Accumulated Unrealized Gains (Losses) on Derivative Instruments Accumulated Foreign Currency Translation Adjustments Total Accumulated Other Comprehensive Loss Balance at January 1, 2018 $ (15,813 ) $ 7,164 $ (33,186 ) $ (41,835 ) Cumulative effect adjustment from the adoption of: ASU 2016-01 (1,880 ) — — (1,880 ) ASU 2018-02 (4,517 ) 1,543 — (2,974 ) Other comprehensive (loss) income during the period, net of tax, before reclassification (20,054 ) 4,498 (9,190 ) (24,746 ) Amount reclassified from accumulated other comprehensive income into net income, net of tax (24 ) (5,348 ) — (5,372 ) Amount reclassified from accumulated other comprehensive income related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale (65 ) — — (65 ) Net other comprehensive loss during the period, net of tax $ (20,143 ) $ (850 ) $ (9,190 ) $ (30,183 ) Balance at December 31, 2018 $ (42,353 ) $ 7,857 $ (42,376 ) $ (76,872 ) Balance at January 1, 2017 $ (29,309 ) $ 4,165 $ (40,184 ) $ (65,328 ) Other comprehensive income during the period, net of tax, before reclassification 14,417 3,010 6,998 24,425 Amount reclassified from accumulated other comprehensive income into net income, net of tax (27 ) (11 ) — (38 ) Amount reclassified from accumulated other comprehensive income related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale (894 ) — — (894 ) Net other comprehensive income during the period, net of tax $ 13,496 $ 2,999 $ 6,998 $ 23,493 Balance at December 31, 2017 $ (15,813 ) $ 7,164 $ (33,186 ) $ (41,835 ) Balance at January 1, 2016 $ (17,674 ) $ (2,193 ) $ (42,841 ) $ (62,708 ) Other comprehensive (loss) income during the period, net of tax, before reclassification (17,554 ) 4,464 2,657 (10,433 ) Amount reclassified from accumulated other comprehensive income (loss) into net income, net of tax (4,641 ) 1,894 — (2,747 ) Amount reclassified from accumulated other comprehensive income related to amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale 10,560 — — 10,560 Net other comprehensive (loss) income during the period, net of tax $ (11,635 ) $ 6,358 $ 2,657 $ (2,620 ) Balance at December 31, 2016 $ (29,309 ) $ 4,165 $ (40,184 ) $ (65,328 )
Reclassification out of Accumulated Other Comprehensive Income	Amount Reclassified from Accumulated Other Comprehensive Income for the Year Ended, Details Regarding the Component of Accumulated Other Comprehensive Income December 31, Impacted Line on the Consolidated Statements of Income 2018 2017 Accumulated unrealized losses on available-for-sale securities Gains included in net income $ 33 $ 45 Gains on investment securities, net 33 45 Income before taxes Tax effect (9 ) (18 ) Income tax expense Net of tax $ 24 $ 27 Net income Accumulated unrealized losses on derivative instruments Amount reclassified to interest expense on deposits $ (7,549 ) $ (1,085 ) Interest on deposits Amount reclassified to interest expense on other borrowings 236 — Interest on other borrowings Amount reclassified to interest expense on junior subordinated debentures — 1,066 Interest on junior subordinated debentures 7,313 19 Income before taxes Tax effect (1,965 ) (8 ) Income tax expense Net of tax $ 5,348 $ 11 Net income

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Summary of Certain Operating Information for Reportable Segments	The following is a summary of certain operating information for reportable segments: (Dollars in thousands) Community Banking Specialty Finance Wealth Management Total Operating Segments Intersegment Eliminations Consolidated 2018 Net interest income $ 791,838 $ 136,981 $ 17,455 $ 946,274 $ 18,629 $ 964,903 Provision for credit losses 28,586 6,246 — 34,832 — 34,832 Non-interest income 238,668 65,898 91,896 396,462 (40,312 ) 356,150 Non-interest expense 681,749 84,248 81,774 847,771 (21,683 ) 826,088 Income tax expense 79,361 30,325 7,281 116,967 — 116,967 Net income $ 240,810 $ 82,060 $ 20,296 $ 343,166 $ — $ 343,166 Total assets at end of year $ 25,438,454 $ 5,073,011 $ 733,384 $ 31,244,849 $ — $ 31,244,849 2017 Net interest income $ 677,481 $ 118,320 $ 18,919 $ 814,720 $ 17,356 $ 832,076 Provision for credit losses 27,059 2,709 — 29,768 — 29,768 Non-interest income 211,354 60,405 84,312 356,071 (36,565 ) 319,506 Non-interest expense 599,455 74,559 77,012 751,026 (19,209 ) 731,817 Income tax expense 87,486 35,775 9,054 132,315 — 132,315 Net income $ 174,835 $ 65,682 $ 17,165 $ 257,682 $ — $ 257,682 Total assets at end of year $ 22,781,923 $ 4,515,766 $ 618,281 $ 27,915,970 $ — $ 27,915,970 2016 Net interest income $ 588,847 $ 98,248 $ 18,611 $ 705,706 $ 16,487 $ 722,193 Provision for credit losses 30,862 3,222 — 34,084 — 34,084 Non-interest income 230,414 49,706 78,478 358,598 (33,168 ) 325,430 Non-interest expense 556,798 66,460 75,108 698,366 (16,681 ) 681,685 Income tax expense 86,933 29,512 8,534 124,979 — 124,979 Net income $ 144,668 $ 48,760 $ 13,447 $ 206,875 $ — $ 206,875 Total assets at end of year $ 21,172,080 $ 3,884,373 $ 612,100 $ 25,668,553 $ — $ 25,668,553

Condensed Parent Company Fina_2

Condensed Parent Company Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Statements of Financial Condition	Statements of Financial Condition December 31, (In thousands) 2018 2017 Assets Cash $ 37,931 $ 78,045 Available-for-sale debt securities and equity securities with readily determinable fair value 12,765 14,461 Investment in and receivable from subsidiaries 3,660,968 3,249,202 Loans, net of unearned income 1,200 1,845 Allowance for loan losses — — Net loans $ 1,200 $ 1,845 Goodwill 8,371 8,371 Other assets 206,902 174,781 Total assets $ 3,928,137 $ 3,526,705 Liabilities and Shareholders’ Equity Other liabilities $ 75,609 $ 66,909 Subordinated notes 139,210 139,088 Other borrowings 192,182 90,203 Junior subordinated debentures 253,566 253,566 Shareholders’ equity 3,267,570 2,976,939 Total liabilities and shareholders’ equity $ 3,928,137 $ 3,526,705
Statements of Income	Statements of Income Years Ended December 31, (In thousands) 2018 2017 2016 Income Dividends and other revenue from subsidiaries $ 171,388 $ 155,969 $ 89,184 Other income 4 2,488 4,344 Total income $ 171,392 $ 158,457 $ 93,528 Expenses Interest expense $ 22,375 $ 19,207 $ 18,498 Salaries and employee benefits 64,726 50,683 34,299 Other expenses 108,038 74,618 62,778 Total expenses $ 195,139 $ 144,508 $ 115,575 (Loss) income before income taxes and equity in undistributed income of subsidiaries $ (23,747 ) $ 13,949 $ (22,047 ) Income tax benefit 34,186 47,139 31,061 Income before equity in undistributed net income of subsidiaries $ 10,439 $ 61,088 $ 9,014 Equity in undistributed net income of subsidiaries 332,727 196,594 197,861 Net income $ 343,166 $ 257,682 $ 206,875
Statements of Cash Flows	Statements of Cash Flows Years Ended December 31, (In thousands) 2018 2017 2016 Operating Activities: Net income $ 343,166 $ 257,682 $ 206,875 Adjustments to reconcile net income to net cash provided by (used for) operating activities Provision for credit losses 56 — — Gain on early extinguishment of debt — — (4,305 ) Depreciation and amortization 11,943 10,783 10,400 Deferred income tax expense (benefit) 502 2,809 (601 ) Stock-based compensation expense 6,025 5,185 3,762 Decrease (increase) in other assets 3,685 1,956 (319 ) Increase in other liabilities 650 9,967 9,618 Equity in undistributed net income of subsidiaries (332,727 ) (196,594 ) (197,861 ) Net Cash Provided by Operating Activities $ 33,300 $ 91,788 $ 27,569 Investing Activities: Capital distributions from (contributions to) subsidiaries, net $ 4,632 $ (42,736 ) $ (118,575 ) Net cash paid for acquisitions, net (87,081 ) — (61,308 ) Other investing activity, net (57,143 ) (28,132 ) (18,051 ) Net Cash Used for Investing Activities $ (139,592 ) $ (70,868 ) $ (197,934 ) Financing Activities: Increase (decrease) in subordinated notes, other borrowings and junior subordinated debentures, net $ 101,910 $ 20,008 $ (26,251 ) Proceeds from the issuance of common stock, net — — 152,911 Issuance of common shares resulting from exercise of stock options, employee stock purchase plan and conversion of common stock warrants 15,903 28,229 15,828 Dividends paid (50,987 ) (40,543 ) (38,568 ) Common stock repurchases for tax withholdings related to stock-based compensation (648 ) (397 ) (616 ) Net Cash Provided by Financing Activities $ 66,178 $ 7,297 $ 103,304 Net (Decrease) Increase in Cash and Cash Equivalents $ (40,114 ) $ 28,217 $ (67,061 ) Cash and Cash Equivalents at Beginning of Year 78,045 49,828 116,889 Cash and Cash Equivalents at End of Year $ 37,931 $ 78,045 $ 49,828

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Common Share	The following table sets forth the computation of basic and diluted earnings per common share for 2018 , 2017 and 2016 : (In thousands, except per share data) 2018 2017 2016 Net income $ 343,166 $ 257,682 $ 206,875 Less: Preferred stock dividends 8,200 9,778 14,513 Net income applicable to common shares—Basic (A) $ 334,966 $ 247,904 $ 192,362 Add: Dividends on convertible preferred stock, if dilutive — 1,578 6,313 Net income applicable to common shares—Diluted (B) $ 334,966 $ 249,482 $ 198,675 Weighted average common shares outstanding (C) 56,300 54,703 50,278 Effect of dilutive potential common shares: Common stock equivalents 908 998 894 Convertible preferred stock, if dilutive — 985 3,100 Total dilutive potential common shares 908 1,983 3,994 Weighted average common shares and effect of dilutive potential common shares (D) 57,208 56,686 54,272 Net income per common share: Basic (A/C) $ 5.95 $ 4.53 $ 3.83 Diluted (B/D) 5.86 4.40 3.66

Quarterly Financial Summary (_2

Quarterly Financial Summary (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Summary of Quarterly Financial Information	The following is a summary of quarterly financial information for the years ended December 31, 2018 and 2017 : 2018 Quarters 2017 Quarters (In thousands, except per share data) First Second Third Fourth First Second Third Fourth Interest income $ 261,205 284,047 304,962 320,596 $ 215,759 231,181 247,688 251,840 Interest expense 36,123 45,877 57,399 66,508 23,179 26,772 31,700 32,741 Net interest income 225,082 238,170 247,563 254,088 192,580 204,409 215,988 219,099 Provision for credit losses 8,346 5,043 11,042 10,401 5,209 8,891 7,896 7,772 Net interest income after provision for credit losses 216,736 233,127 236,521 243,687 187,371 195,518 208,092 211,327 Non-interest income, excluding net securities gains (losses) 86,030 95,221 99,840 77,957 68,820 89,925 79,692 81,024 (Losses) gains on investment securities, net (351 ) 12 90 (2,649 ) (55 ) 47 39 14 Non-interest expense 194,349 206,769 213,637 211,333 168,118 183,544 183,575 196,580 Income before taxes 108,066 121,591 122,814 107,662 88,018 101,946 104,248 95,785 Income tax expense 26,085 32,011 30,866 28,005 29,640 37,049 38,622 27,004 Net income $ 81,981 89,580 91,948 79,657 $ 58,378 64,897 65,626 68,781 Preferred stock dividends 2,050 2,050 2,050 2,050 3,628 2,050 2,050 2,050 Net income applicable to common shares $ 79,931 87,530 89,898 77,607 $ 54,750 62,847 63,576 66,731 Net income per common share: Basic $ 1.42 $ 1.55 $ 1.59 $ 1.38 $ 1.05 $ 1.15 $ 1.14 $ 1.19 Diluted 1.40 1.53 1.57 1.35 1.00 1.11 1.12 1.17 Cash dividends declared per common share 0.19 0.19 0.19 0.19 0.14 0.14 0.14 0.14

Summary Of Significant Accoun_3

Summary Of Significant Accounting Policies (Narrative) (Details) $ in Thousands	Jan. 01, 2018USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)contracts	Dec. 31, 2017USD ($)contracts
Lease term			7 years
Other real estate owned			$ 24,800	$ 40,600
Bank-owned life insurance			$ 147,900	$ 145,900
Number of covered call option contracts outstanding | contracts			0	0
Tax Act, provisional tax benefit				$ 7,600
Tax Act, measurement period adjustment, tax benefit		$ 1,200	$ 1,200
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	$ (2,974)
ASU 2016-01
Cumulative effect adjustment from the adoption of ASUs	1,880
ASU 2017-12
Cumulative effect adjustment from the adoption of ASUs	116
Loans	116
Accumulated other comprehensive income (loss)
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	(2,974)
Accumulated other comprehensive income (loss) | ASU 2016-01
Cumulative effect adjustment from the adoption of ASUs	1,880
Retained earnings
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	2,974
Retained earnings | ASU 2016-01
Cumulative effect adjustment from the adoption of ASUs	(1,880)
Retained earnings | ASU 2017-12
Cumulative effect adjustment from the adoption of ASUs	$ 116
Minimum
Tax benefit realized on settlement, percentage			50.00%
Maximum
Finite-lived intangibles, useful life			20 years
Furniture, fixtures and equipment | Minimum
Premises and equipment, useful lives			2 years
Furniture, fixtures and equipment | Maximum
Premises and equipment, useful lives			15 years
Software and computer-related equipment | Minimum
Premises and equipment, useful lives			2 years
Software and computer-related equipment | Maximum
Premises and equipment, useful lives			5 years
Buildings and improvements | Minimum
Premises and equipment, useful lives			7 years
Buildings and improvements | Maximum
Premises and equipment, useful lives			39 years
Land improvements
Premises and equipment, useful lives			15 years

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Details) - Scenario, Forecast - ASU 2016-02 $ in Millions	Jan. 01, 2019USD ($)
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of use asset	$ 150
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of use asset	$ 190

Investment Securities (Marketab

Investment Securities (Marketable Securities) (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	$ 2,185,494,000	$ 1,833,069,000
Available-for-sale securities, Gross unrealized gains	6,780,000	6,624,000
Available-for-sale securities, Gross unrealized losses	(66,193,000)	(36,027,000)
Available-for-sale securities, fair value	2,126,081,000	1,803,666,000
Held-to-maturity securities	1,067,439,000	826,449,000
Held-to-maturity securities, Gross unrealized gains	2,241,000	2,691,000
Held-to-maturity securities, Gross unrealized losses	(33,584,000)	(16,624,000)
Held-to-maturity securities, fair value	1,036,096,000	812,516,000
Equity securities, FV-NI, cost	34,410,000	0
Equity securities, FV-NI, accumulated unrealized gain	1,532,000	0
Equity securities, FV-NI, accumulated unrealized loss	(1,225,000)	0
Equity securities with readily determinable fair value	34,717,000	0
U.S. Treasury
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	126,199,000	144,904,000
Available-for-sale securities, Gross unrealized gains	391,000	0
Available-for-sale securities, Gross unrealized losses	(186,000)	(1,082,000)
Available-for-sale securities, fair value	126,404,000	143,822,000
U.S. Government agencies
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	139,420,000	157,638,000
Available-for-sale securities, Gross unrealized gains	917,000	2,000
Available-for-sale securities, Gross unrealized losses	(30,000)	(725,000)
Available-for-sale securities, fair value	140,307,000	156,915,000
Held-to-maturity securities	814,864,000	579,062,000
Held-to-maturity securities, Gross unrealized gains	1,141,000	23,000
Held-to-maturity securities, Gross unrealized losses	(28,576,000)	(14,066,000)
Held-to-maturity securities, fair value	787,429,000	565,019,000
Municipal
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	136,831,000	113,197,000
Available-for-sale securities, Gross unrealized gains	2,427,000	2,712,000
Available-for-sale securities, Gross unrealized losses	(768,000)	(557,000)
Available-for-sale securities, fair value	138,490,000	115,352,000
Held-to-maturity securities	252,575,000	247,387,000
Held-to-maturity securities, Gross unrealized gains	1,100,000	2,668,000
Held-to-maturity securities, Gross unrealized losses	(5,008,000)	(2,558,000)
Held-to-maturity securities, fair value	248,667,000	247,497,000
Corporate notes, financial issuers
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	97,079,000	30,309,000
Available-for-sale securities, Gross unrealized gains	35,000	43,000
Available-for-sale securities, Gross unrealized losses	(7,069,000)	(301,000)
Available-for-sale securities, fair value	90,045,000	30,051,000
Corporate notes, other
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	1,000,000	1,000,000
Available-for-sale securities, Gross unrealized gains	0	0
Available-for-sale securities, Gross unrealized losses	0	(1,000)
Available-for-sale securities, fair value	1,000,000	999,000
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	1,641,146,000	1,291,695,000
Available-for-sale securities, Gross unrealized gains	2,510,000	446,000
Available-for-sale securities, Gross unrealized losses	(57,317,000)	(31,955,000)
Available-for-sale securities, fair value	1,586,339,000	1,260,186,000
Collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	43,819,000	60,092,000
Available-for-sale securities, Gross unrealized gains	500,000	64,000
Available-for-sale securities, Gross unrealized losses	(823,000)	(617,000)
Available-for-sale securities, fair value	43,496,000	59,539,000
Equity securities with readily determinable fair value
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, amortized cost	0	34,234,000
Available-for-sale securities, Gross unrealized gains	0	3,357,000
Available-for-sale securities, Gross unrealized losses	0	(789,000)
Available-for-sale securities, fair value	0	$ 36,802,000
Subprime
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, fair value	$ 0

Investment Securities (Schedule

Investment Securities (Schedule of Investment Securities Portfolio Continuous Unrealized Loss Position) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	$ 168,705	$ 250,113
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	(3,229)	(2,012)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	1,476,248	1,292,730
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	(62,964)	(34,015)
Available-for-sale, continuous unrealized loss position, Fair value	1,644,953	1,542,843
Available-for-sale, continuous unrealized loss position, Unrealized losses	(66,193)	(36,027)
Held-to-maturity securities
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, Fair value	38,239	298,750
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, Unrealized loss	(637)	(4,267)
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, Fair value	759,540	352,599
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, Unrealized loss	(32,947)	(12,357)
Held-to-maturity securities, continuous unrealized loss position, Fair value	797,779	651,349
Held-to-maturity securities, continuous unrealized loss position, Unrealized loss	(33,584)	(16,624)
U.S. Treasury
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	5,485	24,811
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	(5)	(215)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	24,829	119,011
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	(181)	(867)
Available-for-sale, continuous unrealized loss position, Fair value	30,314	143,822
Available-for-sale, continuous unrealized loss position, Unrealized losses	(186)	(1,082)
U.S. Government agencies
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	0	14,462
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	0	(69)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	11,167	141,471
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	(30)	(656)
Available-for-sale, continuous unrealized loss position, Fair value	11,167	155,933
Available-for-sale, continuous unrealized loss position, Unrealized losses	(30)	(725)
Held-to-maturity securities
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, Fair value	0	241,849
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, Unrealized loss	0	(3,263)
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, Fair value	601,238	300,200
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, Unrealized loss	(28,576)	(10,803)
Held-to-maturity securities, continuous unrealized loss position, Fair value	601,238	542,049
Held-to-maturity securities, continuous unrealized loss position, Unrealized loss	(28,576)	(14,066)
Municipal
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	10,676	28,221
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	(178)	(256)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	22,147	15,840
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	(590)	(301)
Available-for-sale, continuous unrealized loss position, Fair value	32,823	44,061
Available-for-sale, continuous unrealized loss position, Unrealized losses	(768)	(557)
Held-to-maturity securities
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, Fair value	38,239	56,901
Held-to-maturity securities, continuous unrealized loss position, less than 12 months, Unrealized loss	(637)	(1,004)
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, Fair value	158,302	52,399
Held-to-maturity securities, continuous unrealized loss position, 12 months or longer, Unrealized loss	(4,371)	(1,554)
Held-to-maturity securities, continuous unrealized loss position, Fair value	196,541	109,300
Held-to-maturity securities, continuous unrealized loss position, Unrealized loss	(5,008)	(2,558)
Corporate notes, financial issuers
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	37,076	1,210
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	(2,921)	(1)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	42,934	5,665
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	(4,148)	(300)
Available-for-sale, continuous unrealized loss position, Fair value	80,010	6,875
Available-for-sale, continuous unrealized loss position, Unrealized losses	(7,069)	(301)
Corporate notes, other
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	0	0
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	0	0
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	0	999
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	0	(1)
Available-for-sale, continuous unrealized loss position, Fair value	0	999
Available-for-sale, continuous unrealized loss position, Unrealized losses	0	(1)
Mortgage-backed securities
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	114,958	137,255
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	(124)	(915)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	1,340,916	989,971
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	(57,193)	(31,040)
Available-for-sale, continuous unrealized loss position, Fair value	1,455,874	1,127,226
Available-for-sale, continuous unrealized loss position, Unrealized losses	(57,317)	(31,955)
Collateralized mortgage obligations
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value	510	35,038
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses	(1)	(213)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value	34,255	13,719
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses	(822)	(404)
Available-for-sale, continuous unrealized loss position, Fair value	34,765	48,757
Available-for-sale, continuous unrealized loss position, Unrealized losses	$ (823)	(617)
Equity securities with readily determinable fair value
Available-for-sale securities
Available-for-sale, continuous unrealized losses existing for less than 12 months, Fair value		9,116
Available-for-sale, continuous unrealized losses existing for less than 12 months, Unrealized losses		(343)
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Fair value		6,054
Available-for-sale, continuous unrealized losses existing for greater than 12 months, Unrealized losses		(446)
Available-for-sale, continuous unrealized loss position, Fair value		15,170
Available-for-sale, continuous unrealized loss position, Unrealized losses		$ (789)

Investment Securities (Schedu_2

Investment Securities (Schedule of Available-for-Sale Investment Securities Gross Gains and Gross Losses Realized) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Realized gains on investment securities									$ 1,144	$ 147	$ 9,399
Realized losses on investment securities									(1,111)	(102)	(1,754)
Net realized gains on investment securities									33	45	7,645
Unrealized gains on equity securities with readily determinable fair value									2,771	0	0
Unrealized losses on equity securities with readily determinable fair value									(4,910)	0	0
Net unrealized losses on equity securities with readily determinable fair value									(2,139)	0	0
Upward adjustments of equity securities without readily determinable fair values									325	0	0
Downward adjustments of equity securities without readily determinable fair values									0	0	0
Impairment of equity securities without readily determinable fair values									(1,117)	0	0
Adjustment and impairment, net, of equity securities without readily determinable fair values									(792)	0	0
Other than temporary impairment charges									0	0	0
(Losses) gains on investment securities, net	$ (2,649)	$ 90	$ 12	$ (351)	$ 14	$ 39	$ 47	$ (55)	(2,898)	45	7,645
Proceeds from sales of available-for-sale securities									214,196	344,674	2,194,278
Proceeds from sales of equity securities with readily determinable fair value									1,895	0	0
Proceeds from sales and capital distributions of equity securities without readily determinable fair value									$ 1,324	$ 0	$ 0

Investment Securities (Contract

Investment Securities (Contractual Maturities of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Available-for-sale securities
Available-for-sale securities, due in one year or less, amortized cost	$ 82,206	$ 300,833
Available-for-sale securities, due in one year or less, fair value	82,153	299,285
Available-for-sale securities, due in one to five years, amortized cost	168,855	97,019
Available-for-sale securities, due in one to five years, fair value	169,307	97,326
Available-for-sale securities, due in five to ten years, amortized cost	121,129	33,947
Available-for-sale securities, due in five to ten years, fair value	115,206	35,029
Available-for-sale securities, due after ten years, amortized cost	128,339	15,249
Available-for-sale securities, due after ten years, fair value	129,580	15,499
Available-for-sale securities, amortized cost	2,185,494	1,833,069
Available-for-sale securities, fair value	2,126,081	1,803,666
Available-for-sale securities, amortized cost		1,833,069
Available-for-sale securities, fair value		1,803,666
Held-to-maturity securities
Held-to-maturity securities, due in one year or less, amortized cost	10,009	170
Held-to-maturity securities, due in one year or less, fair value	9,979	171
Held-to-maturity securities, due in one to five years, amortized cost	29,436	38,392
Held-to-maturity securities, due in one to five years, fair value	28,995	38,012
Held-to-maturity securities, due in five to ten years, amortized cost	295,897	205,227
Held-to-maturity securities, due in five to ten years, fair value	290,206	203,680
Held-to-maturity securities, due after ten years, amortized cost	732,097	582,660
Held-to-maturity securities, due after ten years, fair value	706,916	570,653
Held-to-maturity securities	1,067,439	826,449
Held-to-maturity securities, fair value	1,036,096	812,516
Mortgage-backed
Available-for-sale securities
Available-for-sale securities, without single maturity, amortized cost	1,684,965	1,351,787
Available-for-sale securities, without single maturity, fair value	1,629,835	1,319,725
Equity securities with readily determinable fair value
Available-for-sale securities
Available-for-sale equity securities, amortized cost		34,234
Available-for-sale equity securities, fair value		36,802
Available-for-sale securities, amortized cost	0	34,234
Available-for-sale securities, fair value	$ 0	$ 36,802

Investment Securities (Narrativ

Investment Securities (Narrative) (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018USD ($)securities	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)securities	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Debt Securities, Available-for-sale [Line Items]
Securities owned not readily marketable	$ 26,600								$ 26,600
Upward adjustments of equity securities without readily determinable fair values									325	$ 0	$ 0
Downward adjustments of equity securities without readily determinable fair values									0	0	0
Impairment of equity securities without readily determinable fair values									1,117	0	0
Income tax (benefit) expense	28,005	$ 30,866	$ 32,011	$ 26,085	$ 27,004	$ 38,622	$ 37,049	$ 29,640	116,967	132,315	124,979
Investment securities pledged as collateral	$ 1,700,000				$ 1,700,000				$ 1,700,000	1,700,000
Number of securities by a single non-government sponsored issuer exceeding 10% of shareholders' equity | securities	0								0
Available-for-sale debt securities
Debt Securities, Available-for-sale [Line Items]
Income tax (benefit) expense									$ (737)	$ 18	$ 2,900

Loans (Summary of Loan Portfoli

Loans (Summary of Loan Portfolio) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Loans [Line Items]
Loans, net of unearned income	$ 23,820,691	$ 21,640,797
Total loans, percentage	100.00%	100.00%
Commercial
Loans [Line Items]
Loans, net of unearned income	$ 7,828,538	$ 6,787,677
Total loans, percentage	33.00%	31.00%
Commercial real estate
Loans [Line Items]
Loans, net of unearned income	$ 6,933,252	$ 6,580,618
Total loans, percentage	29.00%	30.00%
Home equity
Loans [Line Items]
Loans, net of unearned income	$ 552,343	$ 663,045
Total loans, percentage	2.00%	3.00%
Residential real estate
Loans [Line Items]
Loans, net of unearned income	$ 1,002,464	$ 832,120
Total loans, percentage	4.00%	4.00%
Premium finance receivables | Commercial
Loans [Line Items]
Loans, net of unearned income	$ 2,841,659	$ 2,634,565
Total loans, percentage	12.00%	12.00%
Premium finance receivables | Life insurance
Loans [Line Items]
Loans, net of unearned income	$ 4,541,794	$ 4,035,059
Total loans, percentage	19.00%	19.00%
Consumer and other
Loans [Line Items]
Loans, net of unearned income	$ 120,641	$ 107,713
Total loans, percentage	1.00%	1.00%

Loans (Unpaid Principal Balance

Loans (Unpaid Principal Balance and Carrying Value of Acquired Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Abstract]
Unpaid Principal Balance	$ 341,555	$ 375,237
Carrying Value	$ 318,394	$ 350,690

Loans (Schedule of Loans Acquir

Loans (Schedule of Loans Acquired with Deteriorated Credit Quality) (Details) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 07, 2018	Aug. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Less: Accretable yield	$ 34,876			$ 36,565	$ 49,408
American Enterprise Bank
Business Acquisition [Line Items]
Contractually required payments including interest		$ 31,750
Less: Nonaccretable difference		3,813
Cash flows expected to be collected		27,937
Less: Accretable yield		3,970
Fair value of PCI loans acquired		$ 23,967
Delaware Place Bank
Business Acquisition [Line Items]
Contractually required payments including interest			$ 13,385
Less: Nonaccretable difference			1,197
Cash flows expected to be collected			12,188
Less: Accretable yield			2,205
Fair value of PCI loans acquired			$ 9,983

Loans (Activity Related to Accr

Loans (Activity Related to Accretable Yield of Loans Acquired with Evidence of Credit Quality Deterioration Since Origination) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Accretable yield, beginning balance	$ 36,565	$ 49,408
Acquisitions	6,175	426
Accretable yield amortized to interest income	(16,711)	(21,512)
Accretable yield amortized to indemnification asset/liability	0	(1,087)
Reclassification from nonaccretable difference	4,835	7,805
Increases (Decreases) in interest cash flows due to payments and changes in interest rates	4,012	1,525
Accretable yield, ending balance	$ 34,876	$ 36,565

Loans (Narrative) (Details)

Loans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Loans [Line Items]
Deferred discounts, finance charges and Interest Included in receivables	$ 4,500	$ 9,300
Federal Home Loan Bank advances	426,326	559,663
Accretion to interest income	16,711	21,512
Federal Agency Borrowings
Loans [Line Items]
Loans pledged as collateral	6,100,000	6,400,000
Federal Home Loan Bank Advances
Loans [Line Items]
Loans pledged as collateral	5,700,000
Federal Reserve Bank Advances
Loans [Line Items]
Loans pledged as collateral	484,600
Premium finance receivables
Loans [Line Items]
Loans and leases receivable, deferred income	$ 112,900	$ 87,000

Allowance for Loan Losses, Al_3

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Schedule of Aging of the Company's Loan Portfolio) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	$ 105,326	$ 77,602
90+ days and still accruing	18,872	22,659
Current	23,526,168	21,408,938
Loans, net of unearned income	23,820,691	21,640,797
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	50,984	15,696
90+ days and still accruing	3,313	877
Current	7,737,729	6,737,479
Loans, net of unearned income	7,828,538	6,787,677
Commercial | Commercial, industrial and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	34,298	11,260
90+ days and still accruing	0	0
Current	5,062,729	4,314,107
Loans, net of unearned income	5,120,096	4,342,505
Commercial | Franchise
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	16,051	2,447
90+ days and still accruing	0	0
Current	924,190	845,150
Loans, net of unearned income	948,979	847,597
Commercial | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	0
90+ days and still accruing	0	0
Current	144,199	190,523
Loans, net of unearned income	144,199	194,523
Commercial | Asset-based lending
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	635	1,550
90+ days and still accruing	0	0
Current	1,022,065	968,576
Loans, net of unearned income	1,026,056	980,466
Commercial | Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	439
90+ days and still accruing	0	0
Current	564,430	410,772
Loans, net of unearned income	565,680	413,172
Commercial | PCI - commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	0
90+ days and still accruing	3,313	877
Current	20,116	8,351
Loans, net of unearned income	23,528	9,414
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	19,129	22,048
90+ days and still accruing	6,241	7,135
Current	6,845,490	6,517,763
Loans, net of unearned income	6,933,252	6,580,618
Commercial real estate | Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	1,554	3,143
90+ days and still accruing	0	0
Current	749,846	742,171
Loans, net of unearned income	760,824	745,514
Commercial real estate | Land
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	107	188
90+ days and still accruing	0	0
Current	141,097	121,140
Loans, net of unearned income	141,481	126,484
Commercial real estate | Office
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	3,629	2,438
90+ days and still accruing	0	0
Current	929,739	887,937
Loans, net of unearned income	939,322	894,833
Commercial real estate | Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	285	811
90+ days and still accruing	0	0
Current	885,367	879,796
Loans, net of unearned income	902,248	883,019
Commercial real estate | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	10,753	12,328
90+ days and still accruing	0	0
Current	878,106	938,383
Loans, net of unearned income	892,478	951,527
Commercial real estate | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	311	0
90+ days and still accruing	0	0
Current	970,597	914,610
Loans, net of unearned income	976,560	915,644
Commercial real estate | Mixed use and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	2,490	3,140
90+ days and still accruing	0	0
Current	2,192,105	1,921,501
Loans, net of unearned income	2,205,195	1,935,705
Commercial real estate | PCI - commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	0
90+ days and still accruing	6,241	7,135
Current	98,633	112,225
Loans, net of unearned income	115,144	127,892
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	7,147	8,978
90+ days and still accruing	0	0
Current	541,960	648,915
Loans, net of unearned income	552,343	663,045
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	16,383	17,977
90+ days and still accruing	1,292	5,304
Current	976,926	799,158
Loans, net of unearned income	1,002,464	832,120
Premium finance receivables | Commercial insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	11,335	12,163
90+ days and still accruing	7,799	9,242
Current	2,796,058	2,579,515
Loans, net of unearned income	2,841,659	2,634,565
Premium finance receivables | Life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	0
90+ days and still accruing	0	0
Current	4,340,856	3,820,936
Loans, net of unearned income	4,373,891	3,835,790
Premium finance receivables | PCI - life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	0
90+ days and still accruing	0	0
Current	167,903	199,269
Loans, net of unearned income	167,903	199,269
Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	348	740
90+ days and still accruing	227	101
Current	119,246	105,903
Loans, net of unearned income	120,641	107,713
60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	34,176	33,260
60 to 89 Days Past Due | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	1,651	4,218
60 to 89 Days Past Due | Commercial | Commercial, industrial and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	1,451	3,746
60 to 89 Days Past Due | Commercial | Franchise
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	0
60 to 89 Days Past Due | Commercial | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	0
60 to 89 Days Past Due | Commercial | Asset-based lending
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	200	283
60 to 89 Days Past Due | Commercial | Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	3
60 to 89 Days Past Due | Commercial | PCI - commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	186
60 to 89 Days Past Due | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	10,826	4,346
60 to 89 Days Past Due | Commercial real estate | Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	0
60 to 89 Days Past Due | Commercial real estate | Land
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	170	0
60 to 89 Days Past Due | Commercial real estate | Office
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	877	0
60 to 89 Days Past Due | Commercial real estate | Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	0
60 to 89 Days Past Due | Commercial real estate | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	1,890	668
60 to 89 Days Past Due | Commercial real estate | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	77	0
60 to 89 Days Past Due | Commercial real estate | Mixed use and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	1,617	1,423
60 to 89 Days Past Due | Commercial real estate | PCI - commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	6,195	2,255
60 to 89 Days Past Due | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	131	518
60 to 89 Days Past Due | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	1,692	1,303
60 to 89 Days Past Due | Premium finance receivables | Commercial insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	11,382	17,796
60 to 89 Days Past Due | Premium finance receivables | Life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	8,407	4,837
60 to 89 Days Past Due | Premium finance receivables | PCI - life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	0
60 to 89 Days Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	87	242
30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	136,149	98,338
30 to 59 Days Past Due | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	34,861	29,407
30 to 59 Days Past Due | Commercial | Commercial, industrial and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	21,618	13,392
30 to 59 Days Past Due | Commercial | Franchise
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	8,738	0
30 to 59 Days Past Due | Commercial | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	4,000
30 to 59 Days Past Due | Commercial | Asset-based lending
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	3,156	10,057
30 to 59 Days Past Due | Commercial | Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	1,250	1,958
30 to 59 Days Past Due | Commercial | PCI - commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	99	0
30 to 59 Days Past Due | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	51,566	29,326
30 to 59 Days Past Due | Commercial real estate | Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	9,424	200
30 to 59 Days Past Due | Commercial real estate | Land
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	107	5,156
30 to 59 Days Past Due | Commercial real estate | Office
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	5,077	4,458
30 to 59 Days Past Due | Commercial real estate | Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	16,596	2,412
30 to 59 Days Past Due | Commercial real estate | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	1,729	148
30 to 59 Days Past Due | Commercial real estate | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	5,575	1,034
30 to 59 Days Past Due | Commercial real estate | Mixed use and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	8,983	9,641
30 to 59 Days Past Due | Commercial real estate | PCI - commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	4,075	6,277
30 to 59 Days Past Due | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	3,105	4,634
30 to 59 Days Past Due | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	6,171	8,378
30 to 59 Days Past Due | Premium finance receivables | Commercial insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	15,085	15,849
30 to 59 Days Past Due | Premium finance receivables | Life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	24,628	10,017
30 to 59 Days Past Due | Premium finance receivables | PCI - life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	0	0
30 to 59 Days Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 to 89 days past due	$ 733	$ 727

Allowance for Loan Losses, Al_4

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of Recorded Investment Based on Performance of Loans by Class) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	$ 23,820,691	$ 21,640,797
Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	23,707,457	21,550,635
Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	113,234	90,162
Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	7,828,538	6,787,677
Commercial | Commercial, industrial and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	5,120,096	4,342,505
Commercial | Franchise
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	948,979	847,597
Commercial | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	144,199	194,523
Commercial | Asset-based lending
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,026,056	980,466
Commercial | Leases
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	565,680	413,172
Commercial | PCI - commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	23,528	9,414
Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	7,777,554	6,771,981
Commercial | Performing | Commercial, industrial and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	5,085,798	4,331,245
Commercial | Performing | Franchise
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	932,928	845,150
Commercial | Performing | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	144,199	194,523
Commercial | Performing | Asset-based lending
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,025,421	978,916
Commercial | Performing | Leases
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	565,680	412,733
Commercial | Performing | PCI - commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	23,528	9,414
Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	50,984	15,696
Commercial | Non-performing | Commercial, industrial and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	34,298	11,260
Commercial | Non-performing | Franchise
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	16,051	2,447
Commercial | Non-performing | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0	0
Commercial | Non-performing | Asset-based lending
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	635	1,550
Commercial | Non-performing | Leases
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0	439
Commercial | Non-performing | PCI - commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0	0
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	6,933,252	6,580,618
Commercial real estate | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	760,824	745,514
Commercial real estate | Land
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	141,481	126,484
Commercial real estate | Office
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	939,322	894,833
Commercial real estate | Industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	902,248	883,019
Commercial real estate | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	892,478	951,527
Commercial real estate | Multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	976,560	915,644
Commercial real estate | Mixed use and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	2,205,195	1,935,705
Commercial real estate | PCI - commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	115,144	127,892
Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	6,914,123	6,558,570
Commercial real estate | Performing | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	759,270	742,371
Commercial real estate | Performing | Land
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	141,374	126,296
Commercial real estate | Performing | Office
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	935,693	892,395
Commercial real estate | Performing | Industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	901,963	882,208
Commercial real estate | Performing | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	881,725	939,199
Commercial real estate | Performing | Multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	976,249	915,644
Commercial real estate | Performing | Mixed use and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	2,202,705	1,932,565
Commercial real estate | Performing | PCI - commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	115,144	127,892
Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	19,129	22,048
Commercial real estate | Non-performing | Construction
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,554	3,143
Commercial real estate | Non-performing | Land
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	107	188
Commercial real estate | Non-performing | Office
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	3,629	2,438
Commercial real estate | Non-performing | Industrial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	285	811
Commercial real estate | Non-performing | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	10,753	12,328
Commercial real estate | Non-performing | Multi-family
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	311	0
Commercial real estate | Non-performing | Mixed use and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	2,490	3,140
Commercial real estate | Non-performing | PCI - commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0	0
Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	552,343	663,045
Home equity | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	545,196	654,067
Home equity | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	7,147	8,978
Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,002,464	832,120
Residential real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	986,081	810,865
Residential real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	16,383	21,255
Premium finance receivables | Commercial insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	2,841,659	2,634,565
Premium finance receivables | Life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	4,373,891	3,835,790
Premium finance receivables | PCI - life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	167,903	199,269
Premium finance receivables | Performing | Commercial insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	2,822,525	2,613,160
Premium finance receivables | Performing | Life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	4,373,891	3,835,790
Premium finance receivables | Performing | PCI - life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	167,903	199,269
Premium finance receivables | Non-performing | Commercial insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	19,134	21,405
Premium finance receivables | Non-performing | Life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0	0
Premium finance receivables | Non-performing | PCI - life insurance loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0	0
Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	120,641	107,713
Consumer and other | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	120,184	106,933
Consumer and other | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	$ 457	$ 780

Allowance for Loan Losses, Al_5

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of Activity in the Allowance for Credit Losses by Loan Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan Losses [Roll Forward]
Allowance for loan losses at beginning of period		$ 137,905	$ 122,291
Other adjustments		(181)	573
Reclassification to/from allowance for unfunded lending-related commitments		(126)	69
Charge-offs		(32,635)	(22,695)
Recoveries		12,975	7,685
Provision for credit losses		34,832	29,982
Allowance for loan losses at period end	$ 137,905	152,770	137,905
Allowance for unfunded lending-related commitments at period end	1,269	1,394	1,269
Allowance for credit losses at period end	139,174	154,164	139,174
Allowance for credit losses, Individually evaluated for impairment	8,037	11,447	8,037
Allowance for credit losses, Collectively evaluated for impairment	130,106	142,057	130,106
Loans, Individually evaluated for impairment	105,412	127,519	105,412
Loans, Collectively evaluated for impairment	21,150,978	23,280,921	21,150,978
Loans, net of unearned income	21,640,797	23,820,691	21,640,797
Loan held at fair value	33,717	93,857	33,717
Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses [Roll Forward]
Allowance for credit losses at period end	1,031	660	1,031
Loans, net of unearned income	350,690	318,394	350,690
Commercial
Allowance for Loan Losses [Roll Forward]
Allowance for loan losses at beginning of period		57,811	44,493
Other adjustments		(3)	16
Reclassification to/from allowance for unfunded lending-related commitments		0	500
Charge-offs		(14,532)	(5,159)
Recoveries		1,457	1,870
Provision for credit losses		23,093	16,091
Allowance for loan losses at period end	57,811	67,826	57,811
Allowance for unfunded lending-related commitments at period end	0	0	0
Allowance for credit losses at period end	57,811	67,826	57,811
Allowance for credit losses, Individually evaluated for impairment	4,464	6,558	4,464
Allowance for credit losses, Collectively evaluated for impairment	52,820	60,749	52,820
Loans, Individually evaluated for impairment	35,612	59,529	35,612
Loans, Collectively evaluated for impairment	6,742,651	7,745,482	6,742,651
Loans, net of unearned income	6,787,677	7,828,538	6,787,677
Loan held at fair value	0	0	0
Commercial | Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses [Roll Forward]
Allowance for credit losses at period end	527	519	527
Loans, net of unearned income	9,414	23,527	9,414
Commercial real estate
Allowance for Loan Losses [Roll Forward]
Allowance for loan losses at beginning of period		55,227	51,422
Other adjustments		(85)	(155)
Reclassification to/from allowance for unfunded lending-related commitments		(126)	(431)
Charge-offs		(1,395)	(4,236)
Recoveries		5,631	2,190
Provision for credit losses		1,015	6,437
Allowance for loan losses at period end	55,227	60,267	55,227
Allowance for unfunded lending-related commitments at period end	1,269	1,394	1,269
Allowance for credit losses at period end	56,496	61,661	56,496
Allowance for credit losses, Individually evaluated for impairment	2,177	4,287	2,177
Allowance for credit losses, Collectively evaluated for impairment	53,938	57,329	53,938
Loans, Individually evaluated for impairment	38,534	33,274	38,534
Loans, Collectively evaluated for impairment	6,414,192	6,784,834	6,414,192
Loans, net of unearned income	6,580,618	6,933,252	6,580,618
Loan held at fair value	0	0	0
Commercial real estate | Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses [Roll Forward]
Allowance for credit losses at period end	381	45	381
Loans, net of unearned income	127,892	115,144	127,892
Home equity
Allowance for Loan Losses [Roll Forward]
Allowance for loan losses at beginning of period		10,493	11,774
Other adjustments		(5)	167
Reclassification to/from allowance for unfunded lending-related commitments		0	0
Charge-offs		(2,245)	(3,952)
Recoveries		541	746
Provision for credit losses		(277)	1,758
Allowance for loan losses at period end	10,493	8,507	10,493
Allowance for unfunded lending-related commitments at period end	0	0	0
Allowance for credit losses at period end	10,493	8,507	10,493
Allowance for credit losses, Individually evaluated for impairment	784	282	784
Allowance for credit losses, Collectively evaluated for impairment	9,709	8,225	9,709
Loans, Individually evaluated for impairment	9,254	12,255	9,254
Loans, Collectively evaluated for impairment	653,791	540,088	653,791
Loans, net of unearned income	663,045	552,343	663,045
Loan held at fair value	0	0	0
Home equity | Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses [Roll Forward]
Allowance for credit losses at period end	0	0	0
Loans, net of unearned income	0	0	0
Residential real estate
Allowance for Loan Losses [Roll Forward]
Allowance for loan losses at beginning of period		6,688	5,714
Other adjustments		(25)	356
Reclassification to/from allowance for unfunded lending-related commitments		0	0
Charge-offs		(1,355)	(1,284)
Recoveries		2,075	452
Provision for credit losses		(189)	1,450
Allowance for loan losses at period end	6,688	7,194	6,688
Allowance for unfunded lending-related commitments at period end	0	0	0
Allowance for credit losses at period end	6,688	7,194	6,688
Allowance for credit losses, Individually evaluated for impairment	586	204	586
Allowance for credit losses, Collectively evaluated for impairment	5,979	6,894	5,979
Loans, Individually evaluated for impairment	21,253	22,064	21,253
Loans, Collectively evaluated for impairment	765,149	877,526	765,149
Loans, net of unearned income	832,120	1,002,464	832,120
Loan held at fair value	33,717	93,857	33,717
Residential real estate | Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses [Roll Forward]
Allowance for credit losses at period end	123	96	123
Loans, net of unearned income	12,001	9,017	12,001
Premium finance receivables
Allowance for Loan Losses [Roll Forward]
Allowance for loan losses at beginning of period		6,846	7,625
Other adjustments		(63)	138
Reclassification to/from allowance for unfunded lending-related commitments		0	0
Charge-offs		(12,228)	(7,335)
Recoveries		3,069	2,128
Provision for credit losses		10,091	4,290
Allowance for loan losses at period end	6,846	7,715	6,846
Allowance for unfunded lending-related commitments at period end	0	0	0
Allowance for credit losses at period end	6,846	7,715	6,846
Allowance for credit losses, Individually evaluated for impairment	0	0	0
Allowance for credit losses, Collectively evaluated for impairment	6,846	7,715	6,846
Loans, Individually evaluated for impairment	0	0	0
Loans, Collectively evaluated for impairment	6,470,355	7,215,550	6,470,355
Loan held at fair value	0	0	0
Premium finance receivables | Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses [Roll Forward]
Allowance for credit losses at period end	0	0	0
Loans, net of unearned income	199,269	167,903	199,269
Consumer and other
Allowance for Loan Losses [Roll Forward]
Allowance for loan losses at beginning of period		840	1,263
Other adjustments		0	51
Reclassification to/from allowance for unfunded lending-related commitments		0	0
Charge-offs		(880)	(729)
Recoveries		202	299
Provision for credit losses		1,099	(44)
Allowance for loan losses at period end	840	1,261	840
Allowance for unfunded lending-related commitments at period end	0	0	0
Allowance for credit losses at period end	840	1,261	840
Allowance for credit losses, Individually evaluated for impairment	26	116	26
Allowance for credit losses, Collectively evaluated for impairment	814	1,145	814
Loans, Individually evaluated for impairment	759	397	759
Loans, Collectively evaluated for impairment	104,840	117,441	104,840
Loans, net of unearned income	107,713	120,641	107,713
Loan held at fair value	0	0	0
Consumer and other | Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses [Roll Forward]
Allowance for credit losses at period end	0	0	0
Loans, net of unearned income	2,114	$ 2,803	$ 2,114
Covered Loans
Allowance for Loan Losses [Roll Forward]
Other adjustments	$ 742

Allowance for Loan Losses, Al_6

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of Activity in the Allowance for Covered Loan Losses) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)
Allowance for Covered Loan Losses [Roll Forward]
Balance at beginning of period	$ 1,322
Allowance for covered loan losses transferred to allowance for loan losses subsequent to loss share termination or expiration	(742)
Provision for covered loan losses before benefit attributable to FDIC loss share agreements	(1,063)
Benefit attributable to FDIC loss share agreements	1,592
Net provision for covered loan losses and transfer from allowance for covered loan losses to allowance for loan losses	(213)
Increase in FDIC indemnification liability	(1,592)
Loans charged-off	(517)
Recoveries of loans charged-off	1,000
Net recoveries	483
Balance at end of period	$ 0

Allowance for Loan Losses, Al_7

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of Impaired Loans, Including Restructured Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Receivables [Abstract]
Impaired loans with an allowance for loan loss required, Recorded Investment	$ 60,219	$ 36,084
Impaired loans with no allowance for loan loss required	67,050	69,004
Total impaired loans	127,269	105,088
Allowance for loan losses related to impaired loans	11,437	8,023
TDRs	66,102	49,786
Reduction of interest income from non-accrual loans	3,422	2,373
Interest income recognized on impaired loans	$ 7,347	$ 6,298	$ 5,500

Allowance for Loan Losses, Al_8

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of Impaired Loans Evaluated for Impairment by Loan Class) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	$ 60,219	$ 36,084
Related Allowance	11,437	8,023
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	67,050	69,004
Loans, net of unearned income, Recorded Investment	127,269	105,088
Loans, net of unearned income, Unpaid Principal Balance	139,246	127,566
Loans, net of unearned income, Average Recorded Investment	133,481	115,261	$ 105,400
Loans, net of unearned income, Interest Income Recognized	7,347	6,298	$ 5,500
Home equity
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	3,133	1,606
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	3,470	1,869
Related Allowance	282	784
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	3,165	1,626
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	131	81
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	9,122	7,648
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	12,383	11,648
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	9,323	9,114
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	564	603
Residential real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	4,011	3,798
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	4,263	3,910
Related Allowance	204	586
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	4,056	3,790
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	159	146
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	18,053	17,455
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	20,765	20,327
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	18,552	17,926
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	883	860
Consumer and other
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	116	26
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	129	28
Related Allowance	116	26
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	119	27
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	7	2
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	281	733
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	407	890
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	293	773
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	20	48
Commercial, industrial and other | Commercial
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	16,703	6,233
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	17,029	7,323
Related Allowance	4,866	3,951
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	17,868	7,220
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	1,181	452
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	18,314	8,460
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	21,501	12,259
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	20,547	10,170
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	1,143	683
Franchise | Commercial
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	16,021	0
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	16,256	0
Related Allowance	1,375	0
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	16,221	0
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	909	0
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	5,152	16,256
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	5,154	16,256
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	5,320	17,089
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	403	780
Asset-based lending | Commercial
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	557	948
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	557	949
Related Allowance	317	355
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	689	1,302
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	50	72
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	207	602
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	601	602
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	569	688
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	51	40
Leases | Commercial
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	1,730	2,331
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	1,730	2,337
Related Allowance	0	158
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	1,812	2,463
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	91	117
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	845	782
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	879	782
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	936	845
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	56	49
Construction | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	1,554	3,097
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	1,554	3,897
Related Allowance	550	403
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	1,554	3,690
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	76	197
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	1,117	1,367
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	1,117	1,678
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	1,218	1,555
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	52	84
Land | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	0	0
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	0	0
Related Allowance	0	0
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	0
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	0	0
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	3,396	3,961
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	3,491	4,192
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	3,751	4,129
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	198	182
Office | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	573	471
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	638	471
Related Allowance	21	5
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	587	481
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	25	24
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	3,629	2,438
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	3,642	6,140
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	3,651	3,484
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	184	330
Industrial | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	0	408
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	0	408
Related Allowance	0	40
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	0	414
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	0	25
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	322	403
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	450	2,010
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	363	1,849
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	30	174
Retail | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	14,633	15,599
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	14,633	15,657
Related Allowance	3,413	1,336
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	14,694	15,736
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	676	624
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	1,592	2,393
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	1,945	3,538
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	1,699	2,486
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	110	221
Multi-family | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	0	0
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	0	0
Related Allowance	0	0
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	0	0
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	0	0
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	1,498	1,231
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	1,595	2,078
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	1,529	1,246
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	55	76
Mixed use and other | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with a related ASC 310 allowance recorded	1,188	1,567
Impaired loans with a related ASC 310 allowance recorded, Unpaid Principal Balance	1,221	1,586
Related Allowance	293	379
Impaired loans with a related ASC 310 allowance recorded, Average Recorded Investment	1,354	1,599
Impaired loans with a related ASC 310 allowance recorded, Interest Income Recognized	66	77
Impaired loans with no related ASC 310 allowance recorded, Recorded Investment	3,522	5,275
Impaired loans with no related ASC 310 allowance recorded, Unpaid Principal Balance	3,836	6,731
Impaired loans with no related ASC 310 allowance recorded, Average Recorded Investment	3,611	5,559
Impaired loans with no related ASC 310 allowance recorded, Interest Income Recognized	$ 227	$ 351

Allowance for Loan Losses, Al_9

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of the Post-Modification Balance of Loans Restructured) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)contracts	Dec. 31, 2017USD ($)contracts	Dec. 31, 2016USD ($)contracts
Financing Receivables, Modifications [Line Items]
Total Count | contracts	71	21	21
Total Balance | $	$ 29,243	$ 24,325	$ 12,897
Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	67	12	19
Total Balance | $	$ 11,132	$ 4,265	$ 12,656
Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	28	9	9
Total Balance | $	$ 2,874	$ 4,915	$ 8,046
Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	3	7	2
Total Balance | $	$ 17,872	$ 17,719	$ 470
Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	1	1
Total Balance | $	$ 239	$ 69	$ 275
Commercial | Commercial, industrial and other
Financing Receivables, Modifications [Line Items]
Total Count | contracts	4	5	3
Total Balance | $	$ 13,441	$ 3,775	$ 345
Commercial | Commercial, industrial and other | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	3	1	3
Total Balance | $	$ 691	$ 95	$ 345
Commercial | Commercial, industrial and other | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	1	0
Total Balance | $	$ 0	$ 2,272	$ 0
Commercial | Commercial, industrial and other | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	3	0
Total Balance | $	$ 12,750	$ 1,408	$ 0
Commercial | Commercial, industrial and other | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	1
Total Balance | $	$ 0	$ 0	$ 275
Commercial | Franchise
Financing Receivables, Modifications [Line Items]
Total Count | contracts	3	3	0
Total Balance | $	$ 5,157	$ 16,256	$ 0
Commercial | Franchise | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	0
Total Balance | $	$ 35	$ 0	$ 0
Commercial | Franchise | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial | Franchise | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	2	3	0
Total Balance | $	$ 5,122	$ 16,256	$ 0
Commercial | Franchise | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial | Asset-based lending
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	0
Total Balance | $	$ 130	$ 0	$ 0
Commercial | Asset-based lending | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	0
Total Balance | $	$ 130	$ 0	$ 0
Commercial | Asset-based lending | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial | Asset-based lending | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial | Asset-based lending | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial | Leases
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	2
Total Balance | $	$ 239	$ 0	$ 2,949
Commercial | Leases | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	2
Total Balance | $	$ 239	$ 0	$ 2,949
Commercial | Leases | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial | Leases | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial | Leases | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial real estate | Office
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	1
Total Balance | $	$ 59	$ 0	$ 450
Commercial real estate | Office | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	1
Total Balance | $	$ 59	$ 0	$ 450
Commercial real estate | Office | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial real estate | Office | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial real estate | Office | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial real estate | Industrial
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	6
Total Balance | $	$ 0	$ 0	$ 7,921
Commercial real estate | Industrial | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	6
Total Balance | $	$ 0	$ 0	$ 7,921
Commercial real estate | Industrial | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	3
Total Balance | $	$ 0	$ 0	$ 7,196
Commercial real estate | Industrial | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial real estate | Industrial | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial real estate | Mixed use and other
Financing Receivables, Modifications [Line Items]
Total Count | contracts	2	1	2
Total Balance | $	$ 455	$ 1,245	$ 150
Commercial real estate | Mixed use and other | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	2	1	2
Total Balance | $	$ 455	$ 1,245	$ 150
Commercial real estate | Mixed use and other | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	0
Total Balance | $	$ 85	$ 0	$ 0
Commercial real estate | Mixed use and other | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Commercial real estate | Mixed use and other | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	0
Total Balance | $	$ 0	$ 0	$ 0
Residential real estate and other
Financing Receivables, Modifications [Line Items]
Total Count | contracts	59	12	7
Total Balance | $	$ 9,762	$ 3,049	$ 1,082
Residential real estate and other | Extension at Below Market Terms
Financing Receivables, Modifications [Line Items]
Total Count | contracts	58	10	5
Total Balance | $	$ 9,523	$ 2,925	$ 841
Residential real estate and other | Reduction of Interest Rate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	27	8	6
Total Balance | $	$ 2,789	$ 2,643	$ 850
Residential real estate and other | Modification To Interest Only Payments
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	1	2
Total Balance | $	$ 0	$ 55	$ 470
Residential real estate and other | Forgiveness of Debt
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	1	0
Total Balance | $	$ 239	$ 69	$ 0

Allowance for Loan Losses, A_10

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Summary of Loans Restructured and Subsequently Defaulted Under the Restructured Terms) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)contracts	Dec. 31, 2017USD ($)contracts	Dec. 31, 2016USD ($)contracts
Financing Receivables, Modifications [Line Items]
Total Count | contracts	71	21	21
Total Balance | $	$ 29,243	$ 24,325	$ 12,897
Total count, payments in default | contracts	15	8	8
Total loans, payments in default | $	$ 7,708	$ 6,978	$ 7,841
Residential real estate and other
Financing Receivables, Modifications [Line Items]
Total Count | contracts	59	12	7
Total Balance | $	$ 9,762	$ 3,049	$ 1,082
Total count, payments in default | contracts	9	3	0
Total loans, payments in default | $	$ 1,957	$ 2,052	$ 0
Commercial, industrial and other | Commercial
Financing Receivables, Modifications [Line Items]
Total Count | contracts	4	5	3
Total Balance | $	$ 13,441	$ 3,775	$ 345
Total count, payments in default | contracts	2	4	1
Total loans, payments in default | $	$ 174	$ 3,681	$ 28
Franchise | Commercial
Financing Receivables, Modifications [Line Items]
Total Count | contracts	3	3	0
Total Balance | $	$ 5,157	$ 16,256	$ 0
Total count, payments in default | contracts	2	0	0
Total loans, payments in default | $	$ 5,122	$ 0	$ 0
Asset-based lending | Commercial
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	0
Total Balance | $	$ 130	$ 0	$ 0
Total count, payments in default | contracts	0	0	0
Total loans, payments in default | $	$ 0	$ 0	$ 0
Leases | Commercial
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	2
Total Balance | $	$ 239	$ 0	$ 2,949
Total count, payments in default | contracts	0	0	0
Total loans, payments in default | $	$ 0	$ 0	$ 0
Office | Commercial real estate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	1	0	1
Total Balance | $	$ 59	$ 0	$ 450
Total count, payments in default | contracts	0	0	1
Total loans, payments in default | $	$ 0	$ 0	$ 450
Industrial | Commercial real estate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	0	0	6
Total Balance | $	$ 0	$ 0	$ 7,921
Total count, payments in default | contracts	0	0	5
Total loans, payments in default | $	$ 0	$ 0	$ 7,347
Mixed use and other | Commercial real estate
Financing Receivables, Modifications [Line Items]
Total Count | contracts	2	1	2
Total Balance | $	$ 455	$ 1,245	$ 150
Total count, payments in default | contracts	2	1	1
Total loans, payments in default | $	$ 455	$ 1,245	$ 16

Allowance for Loan Losses, A_11

Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018USD ($)contracts	Dec. 31, 2017USD ($)contracts	Dec. 31, 2016USD ($)contracts
Financing Receivable, Allowance for Credit Losses [Line Items]
Average recorded investment	$ 133,481,000	$ 115,261,000	$ 105,400,000
Interest income recognized on impaired loans	7,347,000	6,298,000	$ 5,500,000
Loans modified in TDRs	$ 66,102,000	$ 49,786,000
Number of loans | contracts	71	21	21
Allowance for loan losses related to impaired loans	$ 11,437,000	$ 8,023,000
Balance of loans	$ 29,243,000	$ 24,325,000	$ 12,897,000
Weighted average extension term	48 months	35 months	19 months
Weighted average decrease in stated interest rate	1.72%	4.85%	0.34%
Weighted average interest only payment term	7 months	11 months	7 months
Loan forgiveness	$ 8,000	$ 73,000	$ 300,000
Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of loans | contracts	134
Allowance for loan losses related to impaired loans	$ 2,100,000
Interest income from decrease in impairment	113,000	207,000
Residential Real Estate | Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Other real estate owned	4,900,000
In process other real estate owned	$ 14,400,000	$ 9,800,000

Mortgage Servicing Rights (Sche

Mortgage Servicing Rights (Schedule Of Changes In Carrying Value Of MSR) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of year	$ 33,676	$ 19,103	$ 9,092
Additions from loans sold with servicing retained	33,071	18,341	13,091
Additions from acquisitions	13,806	0	0
Estimate of changes in fair value due to:
Payoffs and paydowns	(5,039)	(2,595)	(2,325)
Changes in valuation inputs or assumptions	(331)	(1,173)	(755)
Fair value at end of year	75,183	33,676	19,103
Unpaid principal balance of mortgage loans serviced for others	$ 6,545,870	$ 2,929,133	$ 1,784,760

Business Combinations and Ass_3

Business Combinations and Asset Acquisitions (Narrative) (Details) Loan in Thousands, $ in Thousands

Dec. 14, 2018USD ($)

Aug. 01, 2018USD ($)locations

Jan. 04, 2018USD ($)Loan

Oct. 16, 2017USD ($)

Feb. 14, 2017USD ($)

Nov. 18, 2016USD ($)locations

Mar. 31, 2016USD ($)locations

Jun. 30, 2017USD ($)

Dec. 31, 2018USD ($)

Dec. 31, 2012financial_institution

Dec. 07, 2018USD ($)

Aug. 19, 2016USD ($)

Business Acquisition [Line Items]

Goodwill recorded on acquisition

$ 73,164

Reduction to estimated loss share liability

$ (4,900)

$ (1,658)

Net payment early termination of loss share agreements

$ 15,200

Pre-tax gain on write off

$ 400

Delaware Place Bank

Business Acquisition [Line Items]

Number of locations acquired | locations

1

Fair value of assets acquired

$ 282,800

Fair value of loans acquired

152,700

Fair value of deposits assumed

213,100

Goodwill recorded on acquisition

$ 26,500

First Community Financial Corporation

Business Acquisition [Line Items]

Number of locations acquired | locations

2

Fair value of assets acquired

$ 187,300

Fair value of loans acquired

79,500

Fair value of deposits assumed

150,300

Goodwill recorded on acquisition

$ 13,800

GE Capital Franchise Finance

Business Acquisition [Line Items]

Fair value of loans acquired

$ 561,400

Generations Bancorp Inc

Business Acquisition [Line Items]

Number of locations acquired | locations

1

Fair value of assets acquired

$ 134,200

Fair value of loans acquired

67,400

Fair value of deposits assumed

100,200

Goodwill recorded on acquisition

$ 11,500

FDIC Assisted

Business Acquisition [Line Items]

Number of FDIC-assisted banks acquired | financial_institution

9

Transactions subject to loss share arrangements | financial_institution

8

FDIC loss sharing agreement percentage

80.00%

Elektra

Business Acquisition [Line Items]

Goodwill recorded on acquisition

$ 37,600

Veterans First Mortgage

Business Acquisition [Line Items]

Goodwill recorded on acquisition

$ 9,100

Mortgage-servicing rights acquired, number of loans | Loan

10

Unpaid principal balance of mortgage-servicing rights acquired

$ 1,600,000

American Homestead Mortgage, LLC (AHM)

Business Acquisition [Line Items]

Goodwill recorded on acquisition

$ 1,000

American Enterprise Bank

Business Acquisition [Line Items]

Assets acquired

$ 164,000

Loans acquired

119,300

Deposits assumed

$ 150,800

Business Combinations and Ass_4

Business Combinations and Asset Acquisitions (Summary of FDIC Indemnification Asset) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2018
FDIC Indemnification Asset [Roll Forward]
Balance at beginning of period		$ 16,701
Reductions from reimbursable expenses		(291)
Amortization		1,044
Changes in expected reimbursements from the FDIC for changes in expected credit losses	$ (4,900)	(1,658)
Resolution through payments paid to the FDIC and termination of loss share agreements		(15,796)
Balance at end of period		$ 0

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets (Goodwill Assets by Business Segment) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 501,884
Goodwill Acquired	73,164
Impairment Loss	0
Goodwill Adjustments	(1,907)
Ending balance	573,141
Community banking
Goodwill [Roll Forward]
Beginning balance	429,520
Goodwill Acquired	35,565
Impairment Loss	0
Goodwill Adjustments	0
Ending balance	465,085
Specialty finance
Goodwill [Roll Forward]
Beginning balance	40,250
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	(1,907)
Ending balance	38,343
Wealth management
Goodwill [Roll Forward]
Beginning balance	32,114
Goodwill Acquired	37,599
Impairment Loss	0
Goodwill Adjustments	0
Ending balance	$ 69,713

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets (Summary of Finite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Indefinite-lived Intangible Assets by Major Class [Line Items]
Total other intangible assets, net	$ 49,424	$ 17,621
Community banking
Indefinite-lived Intangible Assets by Major Class [Line Items]
Total net carrying amount	31,760	11,845
Community banking | Core deposit and other intangibles:
Indefinite-lived Intangible Assets by Major Class [Line Items]
Gross carrying amount	55,366	37,272
Accumulated amortization	(29,406)	(25,427)
Net carrying amount	25,960	11,845
Specialty finance | Customer list intangibles:
Indefinite-lived Intangible Assets by Major Class [Line Items]
Gross carrying amount	1,958	1,972
Accumulated amortization	(1,436)	(1,298)
Net carrying amount	522	674
Wealth management | Customer list and other intangibles:
Indefinite-lived Intangible Assets by Major Class [Line Items]
Gross carrying amount	20,430	7,940
Accumulated amortization	(3,288)	(2,838)
Net carrying amount	17,142	5,102
Trademarks | Community banking
Indefinite-lived Intangible Assets by Major Class [Line Items]
Carrying amount	$ 5,800	$ 0

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets (Estimated Amortization) (Details) $ in Thousands	Dec. 31, 2018USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Estimated amortization - 2019	$ 11,342
Estimated amortization - 2020	9,582
Estimated amortization - 2021	6,385
Estimated amortization - 2022	4,957
Estimated amortization - 2023	$ 3,621

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill adjustments	$ 1,907
Goodwill acquired	73,164
Amortization expense	4,571	$ 4,401	$ 4,789
Community banking
Goodwill [Line Items]
Goodwill increase	35,600
Goodwill adjustments	0
Goodwill acquired	35,565
Specialty finance
Goodwill [Line Items]
Goodwill adjustments	1,907
Goodwill acquired	0
Wealth management
Goodwill [Line Items]
Goodwill adjustments	0
Goodwill acquired	$ 37,599
Core deposit intangibles | Community banking
Goodwill [Line Items]
Finite-lived intangibles, useful life	10 years
Customer list intangibles | Specialty finance
Goodwill [Line Items]
Finite-lived intangibles, useful life	18 years
Customer list intangibles | Wealth management
Goodwill [Line Items]
Finite-lived intangibles, useful life	10 years

Premises and Equipment, Net (Su

Premises and Equipment, Net (Summary of Premises and Equipment) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 968,434	$ 913,959
Less: Accumulated depreciation and amortization	297,265	292,064
Total premises and equipment, net	671,169	621,895
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	164,232	147,704
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	586,968	555,636
Furniture, equipment, and computer software
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	201,055	203,657
Construction in progress
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 16,179	$ 6,962

Premises and Equipment, Net (Na

Premises and Equipment, Net (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Depreciation	$ 33.2	$ 31.5	$ 32.1

Deposits (Summary of Deposits)

Deposits (Summary of Deposits) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deposits [Abstract]
Non-interest bearing	$ 6,569,880	$ 6,792,497
NOW and interest bearing demand deposits	2,897,133	2,315,055
Wealth management deposits	2,996,764	2,323,699
Money market	5,704,866	4,515,353
Savings	2,665,194	2,829,373
Time certificates of deposit	5,260,841	4,407,370
Total deposits	$ 26,094,678	$ 23,183,347
Non-interest bearing	25.00%	29.00%
NOW and interest bearing demand deposits	11.00%	10.00%
Wealth management deposits	12.00%	10.00%
Money market	22.00%	20.00%
Savings	10.00%	12.00%
Time certificates of deposit	20.00%	19.00%
Total deposits	100.00%	100.00%

Deposits (Schedule of Maturitie

Deposits (Schedule of Maturities of Time Certificates of Deposit) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deposits [Abstract]
Due within one year	$ 3,213,010	$ 3,167,220
Due in one to two years	1,251,446	969,130
Due in two to three years	710,836	127,548
Due in three to four years	47,979	98,952
Due in four to five years	37,563	44,206
Due after five years	7	314
Total time certificate of deposits	$ 5,260,841	$ 4,407,370

Deposits (Schedule of Maturit_2

Deposits (Schedule of Maturities of Time Deposits Over One Hundred Thousand Dollars) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deposits [Abstract]
Maturing within three months	$ 682,940	$ 695,904
After three but within six months	667,079	614,963
After six but within 12 months	921,547	820,285
After 12 months	1,350,717	784,798
Total	$ 3,622,283	$ 2,915,950

Deposits (Narrative) (Details)

Deposits (Narrative) (Details) - USD ($) $ in Billions	Dec. 31, 2018	Dec. 31, 2017
Deposits [Abstract]
Time deposits of $250,000 or more	$ 1.6	$ 1.3

Federal Home Loan Bank Advanc_3

Federal Home Loan Bank Advances (Summary of Outstanding FHLB Advances) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 426,326	$ 559,663
1.44% advance due January 2018
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	250,000
Interest rate	1.44%
1.49% advance due February 2018
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 0	94,663
Interest rate	1.49%
1.57% advance due June 2019
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 1,991	0
Interest rate	1.57%
1.75% advance due June 2020
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 3,940	0
Interest rate	1.75%
1.72% advance due June 2020
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 2,461	0
Interest rate	1.72%
1.88% advance due June 2021
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 2,934	0
Interest rate	1.88%
4.18% advance due February 2022
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 25,000	25,000
Interest rate	4.18%
1.52% advance due March 2022
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 50,000	50,000
Interest rate	1.52%
1.45% advance due May 2022
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 50,000	50,000
Interest rate	1.45%
1.46% advance due May 2022
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 90,000	90,000
Interest rate	1.46%
1.98% advance due January 2023
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 100,000	0
Interest rate	1.98%
0.93% advance due January 2028
Federal Home Loan Bank, Advances, Branch Of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 100,000	$ 0
Interest rate	0.93%

Federal Home Loan Bank Advanc_4

Federal Home Loan Bank Advances (Narrative) (Details) $ in Millions	Dec. 31, 2018USD ($)Rate
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank advances having varying put dates	$ 365
Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances [Line Items]
Additional borrowings possible	$ 2,800
Federal Home Loan Bank Advances | Weighted Average
Federal Home Loan Bank, Advances [Line Items]
FHLB advances, weighted average interest rate | Rate	1.63%

Subordinated Notes (Narrative)

Subordinated Notes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Subordinated notes		$ 139,210	$ 139,088
Subordinated debt issued, gross	$ 140,000
Proceeds from issuance of subordinated debt	139,100
Debt issuance costs	$ 1,300
Subordinated Debt
Debt Instrument [Line Items]
Interest rate		5.00%
Debt instrument, unamortized discount		$ 790

Other Borrowings (Summary Of Ot

Other Borrowings (Summary Of Other Borrowings) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 18, 2018	Dec. 31, 2017	Dec. 15, 2014
Debt Disclosure [Abstract]
Notes payable	$ 144,461	$ 150,000	$ 41,222	$ 150,000
Short-term borrowings	50,593		17,209
Other	47,722		49,131
Secured borrowings	151,079		158,561
Total other borrowings	$ 393,855		$ 266,123

Other Borrowings (Schedule of F

Other Borrowings (Schedule of Financial Instruments Owned and Pledged as Collateral) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Securities sold under repurchase agreements, gross	$ 62,782
Excess collateral	12,189
Securities Sold under Agreements to Repurchase
Debt Instrument [Line Items]
Securities sold under repurchase agreements	50,593	$ 17,200
Available-for-sale debt securities | Mortgage-backed securities
Debt Instrument [Line Items]
Securities sold under repurchase agreements, gross	21,059
Held-to-maturity securities | U.S. Government agencies
Debt Instrument [Line Items]
Securities sold under repurchase agreements, gross	$ 41,723

Other Borrowings (Narrative) (D

Other Borrowings (Narrative) (Details) $ in Millions	1 Months Ended				12 Months Ended	24 Months Ended	48 Months Ended	54 Months Ended
	Jun. 30, 2018CAD ($)	Dec. 31, 2017CAD ($)	Dec. 31, 2015CAD ($)	Dec. 31, 2014CAD ($)	Dec. 31, 2018USD ($)buildingRate	Dec. 31, 2015CAD ($)	Dec. 31, 2017CAD ($)	Jun. 30, 2018CAD ($)	Sep. 18, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 15, 2014USD ($)
Debt Instrument [Line Items]
Notes payable					$ 144,461,000				$ 150,000,000	$ 41,222,000	$ 150,000,000
Short-term borrowings					50,593,000					17,209,000
Sweep accounts					62,782,000
Other borrowings					47,722,000					49,131,000
Secured borrowings					$ 151,079,000					158,561,000
Base Rate Loan | Federal funds rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					0.50%
Base Rate Loan | Eurodollar rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.00%
Term Facility | Base Rate Loan | Base rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					0.75%
Term Facility | Eurodollar Rate Loan | Eurodollar rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.25%
Revolving Credit Facility
Debt Instrument [Line Items]
Notes payable					$ 0
Commitment fee | Rate					0.20%
Revolving Credit Facility | Base Rate Loan | Base rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					0.50%
Revolving Credit Facility | Eurodollar Rate Loan | Eurodollar rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.25%
Securities Sold under Agreements to Repurchase
Debt Instrument [Line Items]
Securities sold under repurchase agreements					$ 50,593,000					17,200,000
Fixed Rate Promissory Note
Debt Instrument [Line Items]
Number of properties | building					2
Other borrowings					$ 47,700,000
Interest rate					3.36%
Non Recourse Debt
Debt Instrument [Line Items]
Other borrowings										151,000
Receivables Purchase Agreement
Debt Instrument [Line Items]
Interest rate					2.936%
Proceeds from issuance of debt	$ 20	$ 10	$ 10	$ 150		$ 160	$ 170	$ 190
Secured borrowings					$ 139,300,000					135,100,000
Secured Debt
Debt Instrument [Line Items]
Secured borrowings					$ 11,800,000
Credit Agreement | Line of Credit
Debt Instrument [Line Items]
Loans payable to bank									200,000,000
Term Facility
Debt Instrument [Line Items]
Notes payable									150,000,000	$ 41,200,000	75,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Notes payable									$ 50,000,000		$ 75,000,000

Junior Subordinated Debenture_2

Junior Subordinated Debentures (Summary of the Company's Junior Subordinated Debentures) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Subordinated Borrowing [Line Items]
Junior subordinated debentures	$ 253,566,000	$ 253,566,000
Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Junior subordinated debentures	$ 253,566,000	253,566,000
Weighted average interest rate	4.94%
Junior Subordinated Debt | Wintrust Capital Trust III
Subordinated Borrowing [Line Items]
Common Securities	$ 774,000
Trust Preferred Securities	25,000,000
Junior subordinated debentures	$ 25,774,000	25,774,000
Contractual rate	5.69%
Junior Subordinated Debt | Wintrust Statutory Trust IV
Subordinated Borrowing [Line Items]
Common Securities	$ 619,000
Trust Preferred Securities	20,000,000
Junior subordinated debentures	$ 20,619,000	20,619,000
Contractual rate	5.60%
Junior Subordinated Debt | Wintrust Statutory Trust V
Subordinated Borrowing [Line Items]
Common Securities	$ 1,238,000
Trust Preferred Securities	40,000,000
Junior subordinated debentures	$ 41,238,000	41,238,000
Contractual rate	5.40%
Junior Subordinated Debt | Wintrust Capital Trust VII
Subordinated Borrowing [Line Items]
Common Securities	$ 1,550,000
Trust Preferred Securities	50,000,000
Junior subordinated debentures	$ 51,550,000	51,550,000
Contractual rate	4.74%
Junior Subordinated Debt | Wintrust Capital Trust VIII
Subordinated Borrowing [Line Items]
Common Securities	$ 1,238,000
Trust Preferred Securities	25,000,000
Junior subordinated debentures	$ 26,238,000	26,238,000
Contractual rate	4.25%
Junior Subordinated Debt | Wintrust Capital Trust IX
Subordinated Borrowing [Line Items]
Common Securities	$ 1,547,000
Trust Preferred Securities	50,000,000
Junior subordinated debentures	$ 51,547,000	51,547,000
Contractual rate	4.42%
Junior Subordinated Debt | Northview Capital Trust I
Subordinated Borrowing [Line Items]
Common Securities	$ 186,000
Trust Preferred Securities	6,000,000
Junior subordinated debentures	$ 6,186,000	6,186,000
Contractual rate	5.54%
Junior Subordinated Debt | Town Bankshares Capital Trust I
Subordinated Borrowing [Line Items]
Common Securities	$ 186,000
Trust Preferred Securities	6,000,000
Junior subordinated debentures	$ 6,186,000	6,186,000
Contractual rate	5.54%
Junior Subordinated Debt | First Northwest Capital Trust I
Subordinated Borrowing [Line Items]
Common Securities	$ 155,000
Trust Preferred Securities	5,000,000
Junior subordinated debentures	$ 5,155,000	5,155,000
Contractual rate	5.80%
Junior Subordinated Debt | Suburban Illinois Capital Trust II
Subordinated Borrowing [Line Items]
Common Securities	$ 464,000
Trust Preferred Securities	15,000,000
Junior subordinated debentures	$ 15,464,000	15,464,000
Contractual rate	4.54%
Junior Subordinated Debt | Community Financial Shares Statutory Trust II
Subordinated Borrowing [Line Items]
Common Securities	$ 109,000
Trust Preferred Securities	3,500,000
Junior subordinated debentures	$ 3,609,000	$ 3,609,000
Contractual rate	4.41%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust III
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	3.25%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Wintrust Statutory Trust IV
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	2.80%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Wintrust Statutory Trust V
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	2.60%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust VII
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	1.95%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust VIII
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	1.45%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust IX
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	1.63%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Northview Capital Trust I
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Town Bankshares Capital Trust I
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | First Northwest Capital Trust I
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Suburban Illinois Capital Trust II
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	1.75%
Junior Subordinated Debt | London Interbank Offered Rate (LIBOR) | Community Financial Shares Statutory Trust II
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	1.62%

Junior Subordinated Debenture_3

Junior Subordinated Debentures (Narrative) (Details)	1 Months Ended	12 Months Ended
	Jan. 31, 2016USD ($)	Dec. 31, 2018USD ($)trustquarterRate	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Subordinated Borrowing [Line Items]
Percentage ownership interest in subsidiary trusts		100.00%
Number of unconsolidated subsidiary trusts | trust		11
Common securities, approximate percentage of junior subordinated debentures		3.00%
Trust preferred securities, approximate percentage of junior subordinated debentures		97.00%
Gain on early extinguishment		$ 0	$ 0	$ 3,588,000
Junior subordinated debentures		$ 253,566,000	253,566,000
Consecutive quarters of deferred payment | quarter		20
Wintrust Capital Trust VIII
Subordinated Borrowing [Line Items]
Debt acquired	$ 15,000,000
Trust preferred securities, face amount issued	40,000,000
Extinguished amount of junior subordinated debentures	15,000,000
Gain on early extinguishment	$ 4,300,000
Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Junior subordinated debentures		$ 253,566,000	$ 253,566,000
Weighted average interest rate | Rate		4.94%
Tier 2 regulatory capital		$ 245,500,000

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Disaggregation of Revenue by Source (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Wealth management
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 90,963	$ 81,766	$ 76,018
Brokerage and insurance product commissions
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	22,391	22,863	25,519
Trust
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	13,263	12,547	11,993
Asset management
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	55,309	46,356	38,506
Mortgage broker fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,188	1,565	2,834
Service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	36,404	34,513	31,210
Administrative services
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,625	4,165	4,409
Card related fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7,441	5,858	5,495
Other deposit related fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 11,892	$ 11,127	$ 9,555

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Contract Assets, Contract Liabilities and Receivables from Contracts with Customers (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Contract assets	$ 0	$ 0
Contract liabilities	1,727	1,706
Mortgage broker fees receivable	44	69
Administrative services receivable	275	0
Wealth management receivable	13,610	8,102
Card related fees receivable	0	202
Total receivables from contracts with customer	$ 13,929	$ 8,373

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Performance Obligations Unsatisfied at End of Period (Details) $ in Thousands	Dec. 31, 2018USD ($)
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 1,727
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 759
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 369
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 303
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 153
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue from Contract with Customer [Abstract]
Performance obligation unsatisfied or partially unsatisfied	$ 143
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated remaining performance period	1 year

Revenue from Contracts with C_6

Revenue from Contracts with Customers - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)subsidiary	Dec. 31, 2017USD ($)
Revenue from Contract with Customer [Abstract]
Number of wealth management subsidiaries | subsidiary	4
Revenue recognized from contract liability balance | $	$ 369	$ 359

Minimum Lease Commitments (Appr

Minimum Lease Commitments (Approximate Minimum Annual Gross Rental Payments And Gross Rental Income) (Details) $ in Thousands	Dec. 31, 2018USD ($)
Payments
2019 - Payments	$ 15,106
2020 - Payments	16,406
2021 - Payments	15,116
2022 - Payments	14,253
2023 - Payments	13,201
2024 and thereafter - Payments	131,615
Total minimum future amounts	205,697
Receipts
2019 - Receipts	7,533
2020 - Receipts	5,576
2021 - Receipts	5,081
2022 - Receipts	3,636
2023 - Receipts	2,117
2024 and thereafter - Receipts	5,233
Total minimum future amounts	$ 29,176

Minimum Lease Commitments (Narr

Minimum Lease Commitments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Leases [Abstract]
Rent expense	$ 21.2	$ 17.7	$ 17.4
Rental income	$ 11.8	$ 9.8	$ 8.9

Income Taxes (Income Tax Expens

Income Taxes (Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current income taxes:
Federal									$ 44,266	$ 54,977	$ 98,272
State									18,349	12,852	20,041
Foreign									(872)	1,243	(10)
Total current income taxes									61,743	69,072	118,303
Deferred income taxes:
Federal									40,500	51,668	4,464
State									11,705	10,403	(14)
Foreign									3,019	1,172	2,226
Total deferred income taxes									55,224	63,243	6,676
Total income tax expense	$ 28,005	$ 30,866	$ 32,011	$ 26,085	$ 27,004	$ 38,622	$ 37,049	$ 29,640	$ 116,967	$ 132,315	$ 124,979

Income Taxes (Reconciliation of

Income Taxes (Reconciliation of the Differences Between Taxes Computed Using the Statutory Federal Income Tax Rate and Actual Income Tax Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income tax expense using the statutory Federal income tax rate of 21% in 2018, and 35% in 2017 and 2016, on income before income taxes									$ 96,628	$ 136,499	$ 116,149
Increase (decrease) in tax resulting from:
Tax-exempt interest, net of interest expense disallowance									(3,869)	(4,658)	(3,634)
State taxes, net of federal tax benefit									23,584	15,115	13,017
Income earned on bank owned life insurance									(1,002)	(1,167)	(1,198)
Re-measurement of net deferred tax liabilities									(1,209)	(10,402)	0
Transition tax on deferred foreign earnings									0	2,850	0
Meals, entertainment and related expenses									1,840	1,710	1,439
FDIC insurance expense									1,832	0	0
Non-deductible compensation expense									1,366	55	77
Non-deductible compensation expense									(3,107)	(5,470)	0
Foreign subsidiary, net									1,591	(271)	(264)
Tax benefits related to tax credit investments, net									(656)	(698)	(572)
Other, net									(31)	(1,248)	(35)
Total income tax expense	$ 28,005	$ 30,866	$ 32,011	$ 26,085	$ 27,004	$ 38,622	$ 37,049	$ 29,640	$ 116,967	$ 132,315	$ 124,979

Income Taxes (Deferred Tax Asse

Income Taxes (Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Allowance for credit losses	$ 40,342	$ 36,442
Deferred compensation	22,363	12,310
Net unrealized losses on securities included in other comprehensive income	15,430	7,465
Stock-based compensation	7,544	6,898
Federal net operating loss carryforward	5,348	3,063
Loans	4,540	4,943
Other real estate owned	2,429	4,019
AMT credit carryforward	1,395	1,199
Nonaccrued interest	1,357	983
Mortgage banking recourse obligation	632	722
Other	3,744	2,307
Total gross deferred tax assets	105,124	80,351
Deferred tax liabilities:
Equipment leasing	90,306	42,681
Premises and equipment	28,517	23,211
Capitalized servicing rights	16,663	8,916
Goodwill and intangible assets	12,921	7,619
Deferred loan fees and costs	3,446	3,531
Net unrealized gains on derivatives included in other comprehensive income	2,863	3,197
Fair value adjustments on loans	2,833	3,143
Other	5,295	3,433
Total gross deferred liabilities	162,844	95,731
Net deferred tax liabilities	$ (57,720)	$ (15,380)

Income Taxes (Unrecognized Tax

Income Taxes (Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at beginning of year	$ 10,821	$ 11,626	$ 0
Gross increases for tax positions taken in current period	0	0	0
Gross increases for positions taken in prior periods	717		11,626
Gross decreases for positions taken in prior periods		(805)
Unrecognized tax benefits at end of the year	$ 11,538	$ 10,821	$ 11,626

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Income before taxes	$ 107,662	$ 122,814	$ 121,591	$ 108,066	$ 95,785	$ 104,248	$ 101,946	$ 88,018	$ 460,133	$ 389,997	$ 331,854
Tax benefit related to stock-based compensation, recorded to shareholders' equity											230
Tax Act, provisional tax benefit										7,600
Tax Act, measurement period adjustment, tax benefit		$ 1,200							1,200
AMT credit carryforward	1,395				1,199				1,395	1,199
Unrecognized tax benefits	9,300								9,300
Interest income accrued on unrecognized tax benefits	1,100				$ 921				1,100	921
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 25,500								25,500
Geographic distribution, foreign
Operating Loss Carryforwards [Line Items]
Income before taxes									$ 5,300	$ 7,800	$ 7,000

Stock Compensation Plans and _3

Stock Compensation Plans and Other Employee Benefit Plans (Weighted Average Assumptions Used To Determine The Options Fair Value) (Details)	12 Months Ended
	Dec. 31, 2016
Share-based Compensation [Abstract]
Expected dividend yield	0.90%
Expected volatility	25.20%
Risk-free rate	1.30%
Expected option life	4 years 6 months

Stock Compensation Plans and _4

Stock Compensation Plans and Other Employee Benefit Plans (Summary of Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Common Shares
Outstanding at beginning of the period (in shares)	1,084,756	1,698,912	1,551,734
Granted (in shares)	0	0	562,166
Exercised (in shares)	(282,614)	(593,459)	(313,900)
Forfeited or canceled (in shares)	(7,128)	(20,697)	(101,088)
Outstanding at end of the period (in shares)	795,014	1,084,756	1,698,912
Exercisable (in shares)	613,932	562,810	703,892
Vested or expected to vest (in shares)	787,753
Weighted Average Strike Price
Outstanding at beginning of the period (in dollars per share)	$ 41.98	$ 41.50	$ 41.32
Granted (in dollars per share)	0	0	41.04
Exercised (in dollars per share)	41.25	40.57	37.71
Forfeited or canceled (in dollars per share)	39.84	42.83	48
Outstanding at end of the period (in dollars per share)	42.25	41.98	41.50
Exercisable (in dollars per share)	42.54	$ 41.82	$ 39.62
Vested or expected to vest (in dollars per share)	$ 42.26
Stock Options Additional Disclosures
Outstanding, remaining contractual term	3 years 1 month 6 days	4 years	4 years 7 months 6 days
Outstanding, intrinsic value	$ 19,268	$ 43,817	$ 52,790
Exercisable, remaining contractual term	3 years 1 month 6 days	3 years 4 months	3 years 4 months 24 days
Exercisable, intrinsic value	$ 14,705	$ 22,820	$ 23,195
Vested or expected to vest, remaining contractual term	3 years 1 month 6 days
Vested or expected to vest, intrinsic value	$ 19,085

Stock Compensation Plans and _5

Stock Compensation Plans and Other Employee Benefit Plans (Summary of Plans' Restricted Share Award Activity) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restricted shares
Common Shares
Outstanding at the beginning of period (in shares)	127,787	133,425	137,593
Granted (in shares)	35,654	16,552	18,022
Vested and issued (in shares)	(18,324)	(19,639)	(20,007)
Forfeited (in shares)	(1,854)	(2,551)	(2,183)
Outstanding at the end of period (in shares)	143,263	127,787	133,425
Vested, but not issuable, or deferred, at year end (in shares)	90,520	89,723	89,050
Weighted Average Grant-Date Fair Value
Outstanding at beginning of the period (in dollars per share)	$ 53.33	$ 49.94	$ 49.63
Granted (in dollars per share)	84.36	73.16	46.01
Vested and issued (in dollars per share)	54.31	47.13	44.91
Forfeited (in dollars per share)	63.50	52.26	44.18
Outstanding at end of the period (in dollars per share)	60.80	53.33	49.94
Vested, but not issuable, or deferred, at year end (in dollars per share)	$ 51.94	$ 51.64	$ 51.47
Performance shares
Common Shares
Outstanding at the beginning of period (in shares)	359,196	298,180	276,533
Granted (in shares)	134,380	145,853	118,084
Vested and issued (in shares)	(82,307)	(68,712)	(78,410)
Forfeited (in shares)	(14,414)	(16,125)	(18,027)
Outstanding at the end of period (in shares)	396,855	359,196	298,180
Vested, but not issuable, or deferred, at year end (in shares)	21,530	108,143	6,672,000
Weighted Average Grant-Date Fair Value
Outstanding at beginning of the period (in dollars per share)	$ 54.37	$ 43.64	$ 43.01
Granted (in dollars per share)	88.27	72.60	41.02
Vested and issued (in dollars per share)	44.39	46.85	37.90
Forfeited (in dollars per share)	60.05	52.98	41.83
Outstanding at end of the period (in dollars per share)	67.71	54.37	43.64
Vested, but not issuable, or deferred, at year end (in dollars per share)	$ 43.54	$ 44.16	$ 37.98

Stock Compensation Plans and _6

Stock Compensation Plans and Other Employee Benefit Plans (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018USD ($)hourRateshares	Dec. 31, 2017USD ($)shares	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015shares	May 31, 2015shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares) | shares	3,400,000
Options granted (in shares) | shares	0	0	562,166
Stock-based compensation expense	$ 13,500,000	$ 12,900,000	$ 9,300,000
Tax benefit from stock-based compensation arrangements	3,100,000	5,100,000	$ 3,700,000
Options granted, weighted average grant date fair value (in dollars per share) | $ / shares			$ 8.61
Aggregate intrinsic value of options exercised	13,300,000	20,100,000	$ 5,800,000
Tax benefit realized from option exercises	3,500,000	7,800,000	2,300,000
Cash received from option exercises	11,700,000	24,100,000	11,800,000
Unrecognized compensation	$ 15,400,000
Unrecognized compensation period for recognition	2 years
Fair value of shares vested	$ 8,000,000	8,900,000	8,400,000
Number of hours of service required for eligibility | hour	501
Expense for employer contribution to plan	$ 10,400,000	8,900,000	6,600,000
Pension expense (income)	(38,000)	1,200,000	526,000
HPK Financial Corporation
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Projected benefit obligation	4,900,000
Fair value of plan assets	4,700,000
Diamond Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Projected benefit obligation	2,700,000
Fair value of plan assets	1,600,000
Cash Incentive And Retention Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense related to plan	0	0	0
Cash awards paid	0	$ 0	$ 0
Cash awards outstanding	$ 0
Directors Deferred Fee And Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issued to directors (in shares) | shares	18,856	27,508	25,362
Obligation to issue (in shares) | shares	281,910
Available for future issuance (in shares) | shares	74,206
2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares) | shares					5,485,000
2015 and 2007 Plans | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period (in shares)	3 years
2015 and 2007 Plans | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period (in shares)	5 years
Option term	7 years
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares that could be issued based on the grants made to date (in shares) | shares	143,263	127,787	133,425	137,593
Restricted shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period (in shares)	1 year
Restricted shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period (in shares)	5 years
LTIP awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period (in shares)	3 years
LTIP awards | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award payout percentage | Rate	0.00%
LTIP awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option term	7 years
Award payout percentage | Rate	150.00%
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares that could be issued based on the grants made to date (in shares) | shares	396,855	359,196	298,180	276,533
Excess tax benefit over estimate	$ 994,000	$ 975,000	$ 241,000
Performance shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares that could be issued based on the grants made to date (in shares) | shares	585,518
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of shares, percentage of closing price	95.00%
Employee stock purchase plan issuance (in shares) | shares	33,977	35,022	50,920
Compensation expense employee stock purchase plan	$ 0	$ 0	$ 0
Increase in shares authorized (in shares) | shares	200,000
Common stock obligation to issue (in shares) | shares	10,807
Available for future grants (in shares) | shares	216,063

Regulatory Matters (Schedule of

Regulatory Matters (Schedule of Compliance with Minimum Capital Requirements) (Details)	Dec. 31, 2018Rate	Dec. 31, 2017Rate
Regulatory Capital Requirements [Abstract]
Total capital to risk weighted assets	11.60%	12.00%
Tier 1 capital to risk weighted assets	9.70%	9.90%
Common Equity Tier 1 Capital to Risk Weighted Assets	9.30%	9.40%
Tier 1 Leverage Ratio	9.10%	9.30%

Regulatory Matters (Schedule _2

Regulatory Matters (Schedule of Actual Capital Amounts and Ratios) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Ratio	11.60%	12.00%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%
Tier 1 Capital to Risk Weighted Assets, Ratio	9.70%	9.90%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets	9.30%	9.40%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%
Tier 1 Leverage Ratio	9.10%	9.30%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%
Lake Forest Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 424,872	$ 366,407
Total Capital to Risk Weighted Assets, Ratio	12.50%	11.60%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 338,823	$ 317,180
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 402,156	$ 347,924
Tier 1 Capital to Risk Weighted Assets, Ratio	11.90%	11.00%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 271,058	$ 253,744
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 402,156	$ 347,924
Common Equity Tier 1 Capital to Risk Weighted Assets	11.90%	11.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 220,235	$ 206,167
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 402,156	$ 347,924
Tier 1 Leverage Ratio	10.70%	10.30%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 187,634	$ 168,865
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Hinsdale Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 256,166	$ 224,577
Total Capital to Risk Weighted Assets, Ratio	11.90%	11.50%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 220,004	$ 195,125
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 244,036	$ 214,061
Tier 1 Capital to Risk Weighted Assets, Ratio	11.30%	11.00%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 176,003	$ 156,100
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 244,036	$ 214,061
Common Equity Tier 1 Capital to Risk Weighted Assets	11.30%	11.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 143,002	$ 126,831
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 244,036	$ 214,061
Tier 1 Leverage Ratio	10.40%	10.20%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 117,308	$ 105,086
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Wintrust Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 613,037	$ 512,581
Total Capital to Risk Weighted Assets, Ratio	11.50%	11.20%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 533,154	$ 456,230
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 545,649	$ 439,061
Tier 1 Capital to Risk Weighted Assets, Ratio	10.20%	9.60%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 426,523	$ 364,984
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 545,649	$ 439,061
Common Equity Tier 1 Capital to Risk Weighted Assets	10.20%	9.60%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 346,550	$ 296,549
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 545,649	$ 439,061
Tier 1 Leverage Ratio	9.70%	9.20%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 281,090	$ 237,782
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Libertyville Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 161,453	$ 141,723
Total Capital to Risk Weighted Assets, Ratio	11.90%	11.40%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 135,262	$ 124,637
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 152,939	$ 134,310
Tier 1 Capital to Risk Weighted Assets, Ratio	11.30%	10.80%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 108,209	$ 99,709
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 152,939	$ 134,310
Common Equity Tier 1 Capital to Risk Weighted Assets	11.30%	10.80%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 87,920	$ 81,014
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 152,939	$ 134,310
Tier 1 Leverage Ratio	10.00%	9.80%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 76,247	$ 68,404
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Barrington Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 258,301	$ 234,930
Total Capital to Risk Weighted Assets, Ratio	11.10%	12.00%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 231,871	$ 195,409
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 252,189	$ 229,311
Tier 1 Capital to Risk Weighted Assets, Ratio	10.90%	11.70%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 185,497	$ 156,327
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 252,189	$ 229,311
Common Equity Tier 1 Capital to Risk Weighted Assets	10.90%	11.70%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 150,716	$ 127,016
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 252,189	$ 229,311
Tier 1 Leverage Ratio	12.90%	11.80%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 97,759	$ 97,007
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Crystal Lake Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 107,041	$ 95,532
Total Capital to Risk Weighted Assets, Ratio	11.60%	11.30%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 92,542	$ 84,664
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 102,404	$ 91,273
Tier 1 Capital to Risk Weighted Assets, Ratio	11.10%	10.80%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 74,033	$ 67,731
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 102,404	$ 91,273
Common Equity Tier 1 Capital to Risk Weighted Assets	11.10%	10.80%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 60,152	$ 55,031
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 102,404	$ 91,273
Tier 1 Leverage Ratio	9.90%	9.50%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 51,974	$ 48,069
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Northbrook Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 236,201	$ 222,441
Total Capital to Risk Weighted Assets, Ratio	11.10%	11.40%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 213,524	$ 194,764
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 223,849	$ 198,628
Tier 1 Capital to Risk Weighted Assets, Ratio	10.50%	10.20%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 170,819	$ 155,811
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 223,849	$ 198,628
Common Equity Tier 1 Capital to Risk Weighted Assets	10.50%	10.20%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 138,791	$ 126,597
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 223,849	$ 198,628
Tier 1 Leverage Ratio	9.80%	9.50%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 114,125	$ 104,377
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Schaumburg Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 113,797	$ 111,772
Total Capital to Risk Weighted Assets, Ratio	11.40%	11.90%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 100,151	$ 93,752
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 108,338	$ 105,733
Tier 1 Capital to Risk Weighted Assets, Ratio	10.80%	11.30%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 80,120	$ 75,001
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 108,338	$ 105,733
Common Equity Tier 1 Capital to Risk Weighted Assets	10.80%	11.30%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 65,098	$ 60,939
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 108,338	$ 105,733
Tier 1 Leverage Ratio	9.50%	10.10%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 57,111	$ 52,171
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Village Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 151,653	$ 145,517
Total Capital to Risk Weighted Assets, Ratio	11.20%	11.90%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 135,695	$ 121,867
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 142,333	$ 136,807
Tier 1 Capital to Risk Weighted Assets, Ratio	10.50%	11.20%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 108,556	$ 97,494
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 142,333	$ 136,807
Common Equity Tier 1 Capital to Risk Weighted Assets	10.50%	11.20%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 88,201	$ 79,214
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 142,333	$ 136,807
Tier 1 Leverage Ratio	9.50%	9.70%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 75,197	$ 70,182
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Beverly Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 146,054	$ 132,516
Total Capital to Risk Weighted Assets, Ratio	11.80%	11.70%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 123,618	$ 112,810
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 141,140	$ 127,561
Tier 1 Capital to Risk Weighted Assets, Ratio	11.40%	11.30%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 98,894	$ 90,248
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 141,140	$ 127,561
Common Equity Tier 1 Capital to Risk Weighted Assets	11.40%	11.30%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 80,352	$ 73,327
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 141,140	$ 127,561
Tier 1 Leverage Ratio	10.70%	10.80%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 66,109	$ 59,140
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Town Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 208,479	$ 188,987
Total Capital to Risk Weighted Assets, Ratio	11.30%	11.40%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 184,825	$ 166,253
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 199,982	$ 180,943
Tier 1 Capital to Risk Weighted Assets, Ratio	10.80%	10.90%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 147,860	$ 133,003
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 199,982	$ 180,943
Common Equity Tier 1 Capital to Risk Weighted Assets	10.80%	10.90%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 120,136	$ 108,065
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 199,982	$ 180,943
Tier 1 Leverage Ratio	10.00%	10.10%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 100,257	$ 89,617
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Wheaton Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 165,798	$ 151,141
Total Capital to Risk Weighted Assets, Ratio	11.30%	11.40%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 147,354	$ 132,211
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 159,718	$ 135,009
Tier 1 Capital to Risk Weighted Assets, Ratio	10.80%	10.20%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 117,883	$ 105,769
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 159,718	$ 135,009
Common Equity Tier 1 Capital to Risk Weighted Assets	10.80%	10.20%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 95,780	$ 85,937
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 159,718	$ 135,009
Tier 1 Leverage Ratio	9.80%	9.40%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 81,767	$ 72,152
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
State Bank of the Lakes
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 111,530	$ 105,770
Total Capital to Risk Weighted Assets, Ratio	11.10%	11.40%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 100,654	$ 92,518
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 107,234	$ 95,520
Tier 1 Capital to Risk Weighted Assets, Ratio	10.70%	10.30%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 80,523	$ 74,014
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 107,234	$ 95,520
Common Equity Tier 1 Capital to Risk Weighted Assets	10.70%	10.30%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 65,425	$ 60,137
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 107,234	$ 95,520
Tier 1 Leverage Ratio	9.20%	9.20%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 58,068	$ 51,681
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
Old Plank Trail Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 151,889	$ 145,272
Total Capital to Risk Weighted Assets, Ratio	11.40%	11.60%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 132,842	$ 125,642
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 145,779	$ 139,366
Tier 1 Capital to Risk Weighted Assets, Ratio	11.00%	11.10%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 106,273	$ 100,514
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 145,779	$ 139,366
Common Equity Tier 1 Capital to Risk Weighted Assets	11.00%	11.10%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 86,347	$ 81,667
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 145,779	$ 139,366
Tier 1 Leverage Ratio	9.60%	9.90%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 76,096	$ 70,735
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%
St. Charles Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk Weighted Assets, Amount	$ 115,607	$ 105,778
Total Capital to Risk Weighted Assets, Ratio	11.40%	11.40%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 101,337	$ 92,582
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%	10.00%
Tier 1 Capital to Risk Weighted Assets, Amount	$ 111,454	$ 102,251
Tier 1 Capital to Risk Weighted Assets, Ratio	11.00%	11.00%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 81,069	$ 74,066
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, Amount	$ 111,454	$ 102,251
Common Equity Tier 1 Capital to Risk Weighted Assets	11.00%	11.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Amount	$ 65,869	$ 60,178
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%	6.50%
Tier 1 Leverage Ratio, Amount	$ 111,454	$ 102,251
Tier 1 Leverage Ratio	9.80%	9.80%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Amount	$ 56,915	$ 51,907
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%	5.00%

Regulatory Matters (Narrative)

Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Cash dividends paid to parent Company by consolidated subsidiaries	$ 111	$ 122	$ 59
Amount available to be paid as dividends without prior regulatory approval	$ 350.4
Minimum ratio of qualifying total capital to risk-weighted assets	8.00%
Common Equity Tier 1 capital required for capital adequacy to risk weighted assets	4.50%
Tier 1 risk based capital required for capital adequacy to risk weighted assets	6.00%
Tier 1 leverage capital required for capital adequacy to average assets	4.00%
Total Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	10.00%
Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	8.00%
Common Equity Tier 1 Capital to Risk Weighted Assets, To Be Well Capitalized by Regulatory Definition, Ratio	6.50%
Tier 1 Leverage Ratio, To Be Well Capitalized by Regulatory Definition, Ratio	5.00%
Federal Reserve Bank
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Cash reserve requirement	$ 611.1	$ 557.7

Commitments And Contingencies (

Commitments And Contingencies (Details) $ in Thousands	Oct. 17, 2018USD ($)investorplaintiff	Apr. 09, 2018USD ($)	Feb. 03, 2016defendant	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Commitments And Contingencies [Line Items]
Letters of credit outstanding, amount				$ 233,300	$ 195,900
Mortgage loans sold				4,076,887	3,869,137	$ 4,468,984
Additional amount related to loss indemnification claims for residential mortgage loans previously sold to investors				2,400	3,000
Losses charged against indemnification liability				183	1,400
Commitments to invest in partnership				13,600
Commitments to invest in partnership for tax credits				914
Customer balances maintained by clearing broker and subject to indemnification				11,300
Lehman Holdings matter
Commitments And Contingencies [Line Items]
Number of defendants other than Wintrust | defendant			150
JPMC matter
Commitments And Contingencies [Line Items]
Amount of damages sought		$ 4,600
Ponzi scheme matter
Commitments And Contingencies [Line Items]
Amount of damages sought	$ 6,000
Number of plaintiffs | plaintiff	2
Number of investors in plaintiff group | investor	42
Forward commitments to sell mortgage loans
Commitments And Contingencies [Line Items]
Notional amount				481,600	551,900
Commercial, commercial real estate, and construction loans
Commitments And Contingencies [Line Items]
Loans and leases receivable, commitments				4,700,000	4,400,000
Home equity
Commitments And Contingencies [Line Items]
Loans and leases receivable, commitments				807,900	826,500
Residential real estate
Commitments And Contingencies [Line Items]
Loans and leases receivable, commitments				$ 389,700	$ 446,300

Derivative Financial Instrume_3

Derivative Financial Instruments (Schedule of Fair Value of Derivative Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivative Assets	$ 73,172	$ 52,069
Derivative Liabilities	68,088	35,671
Interest rate derivatives
Derivative [Line Items]
Derivative Assets	68,425	48,985
Derivative Liabilities	62,571	33,716
Designated as hedging instrument
Derivative [Line Items]
Derivative Assets	8,906	14,846
Derivative Liabilities	3,412	12
Not designed as hedging instrument
Derivative [Line Items]
Derivative Assets	64,266	37,223
Derivative Liabilities	64,676	35,659
Not designed as hedging instrument | Interest rate derivatives
Derivative [Line Items]
Derivative Assets	59,519	34,139
Derivative Liabilities	59,159	33,704
Not designed as hedging instrument | Interest rate lock commitments
Derivative [Line Items]
Derivative Assets	3,405	2,843
Derivative Liabilities	2,694	269
Not designed as hedging instrument | Forward commitments to sell mortgage loans
Derivative [Line Items]
Derivative Assets	0	14
Derivative Liabilities	1,486	1,457
Not designed as hedging instrument | Foreign currency derivatives
Derivative [Line Items]
Derivative Assets	1,342	227
Derivative Liabilities	1,337	229
Cash flow hedging | Designated as hedging instrument | Interest rate derivatives
Derivative [Line Items]
Derivative Assets	6,270	11,914
Derivative Liabilities	1,656	12
Fair value hedging | Designated as hedging instrument | Interest rate derivatives
Derivative [Line Items]
Derivative Assets	2,636	2,932
Derivative Liabilities	$ 1,756	$ 0

Derivative Financial Instrume_4

Derivative Financial Instruments (Schedule of Cash Flow Hedging Instruments) (Details) - Cash flow hedging - Designated as hedging instrument	Dec. 31, 2018USD ($)
Derivative [Line Items]
Notional Amount	$ 869,643,000
Fair Value Asset (Liability)	4,614,000
June 2,019
Derivative [Line Items]
Notional Amount	200,000,000
Fair Value Asset (Liability)	957,000
July 2,019
Derivative [Line Items]
Notional Amount	250,000,000
Fair Value Asset (Liability)	2,196,000
August 2,019
Derivative [Line Items]
Notional Amount	275,000,000
Fair Value Asset (Liability)	3,117,000
September 2,023
Derivative [Line Items]
Notional Amount	144,643,000
Fair Value Asset (Liability)	$ (1,656,000)

Derivative Financial Instrume_5

Derivative Financial Instruments (Rollforward of Amounts in Accumulated Other Comprehensive Income Related to Interest Rate Swaps Designated as Cash Flow Hedges) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Rollforward of AOCI from Cash Flow Hedging Derivatives [Roll Forward]
Amount of gain recognized in other comprehensive income	$ (1,160)	$ 4,958	$ 10,473
Interest rate derivatives
Rollforward of AOCI from Cash Flow Hedging Derivatives [Roll Forward]
Unrealized gain at beginning of period	11,902	6,944
Amount reclassified from accumulated other comprehensive income to interest expense on deposits and junior subordinated debentures	(7,313)	(19)
Amount of gain recognized in other comprehensive income	6,153	4,977
Unrealized gain at end of period	$ 10,742	$ 11,902	$ 6,944

Derivative Financial Instrume_6

Derivative Financial Instruments (Derivatives in Fair Value Hedging Relationships) (Details) - Interest rate swaps $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Interest and fees on loans
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on fair value hedges	$ (131)
Interest income - investment securities
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on fair value hedges	0
Loans, net of unearned income, excluding covered loans
Derivative Instruments, Gain (Loss) [Line Items]
Carrying amount of hedged assets (liabilities)	135,944
Cumulative amount of fair value hedging adjustment included in carrying amount of hedged assets (liabilities)	(953)
Cumulative amount of fair value hedging adjustment remaining for any hedged assets (liabilities) for which hedge accounting has been discontinued	0
Available-for-sale debt securities
Derivative Instruments, Gain (Loss) [Line Items]
Carrying amount of hedged assets (liabilities)	1,497
Cumulative amount of fair value hedging adjustment included in carrying amount of hedged assets (liabilities)	58
Cumulative amount of fair value hedging adjustment remaining for any hedged assets (liabilities) for which hedge accounting has been discontinued	$ 0

Derivative Financial Instrume_7

Derivative Financial Instruments (Summary Amounts Included in Consolidated Statement of Income Related to Derivatives) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Interest rate swaps and caps | Trading gains (losses), net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments not designated in hedge relationships	$ (75)	$ (848)
Mortgage banking derivatives | Mortgage banking revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments not designated in hedge relationships	(792)	1,314
Covered call options | Fees from covered call options
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments not designated in hedge relationships	3,519	4,402
Foreign exchange contracts | Trading gains (losses), net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative instruments not designated in hedge relationships	$ 20	$ (38)

Derivative Financial Instrume_8

Derivative Financial Instruments (Summary of Interest Rate Derivatives) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivative Assets
Gross Amounts Recognized	$ 73,172	$ 52,069
Derivative Liabilities
Gross Amounts Recognized	68,088	35,671
Interest rate derivatives
Derivative Assets
Gross Amounts Recognized	68,425	48,985
Less: Amounts offset in the Statements of Condition	0	0
Net amount presented in the Statements of Condition	68,425	48,985
Offsetting Derivative Positions	(28,124)	(14,878)
Collateral Posted	(23,810)	(18,060)
Net Credit Exposure	16,491	16,047
Derivative Liabilities
Gross Amounts Recognized	62,571	33,716
Less: Amounts offset in the Statements of Condition	0	0
Net amount presented in the Statements of Condition	62,571	33,716
Offsetting Derivative Positions	(28,124)	(14,878)
Collateral Posted	(2,640)	(2,220)
Net Credit Exposure	$ 31,807	$ 16,618

Derivative Financial Instrume_9

Derivative Financial Instruments (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018USD ($)derivative_instruments	Dec. 31, 2017USD ($)derivative_instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount to be reclassified from accumulated other comprehensive income to interest expense in next twelve months	$ 10,900,000
Interest rate swap terminated
Derivative Instruments, Gain (Loss) [Line Items]
Carrying amount of hedged assets (liabilities)	1,400,000
Cumulative amount of fair value hedging adjustment included in carrying amount of hedged assets (liabilities)	(1,600,000)
Interest rate derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive income on terminated derivative instruments	(7,313,000)	$ (19,000)
Fair value of interest rate derivatives in a net liability position	5,300,000
Forward commitments to sell mortgage loans
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	481,600,000	$ 551,900,000
Interest rate lock commitments
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	235,800,000
Foreign currency derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 40,300,000
Covered call options
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivative_instruments	0	0
Cash flow hedging | Interest rate swap terminated
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivative_instruments	5
Notional amount	$ 650,000,000
Cash flow hedging | Interest expense | Interest rate swap terminated
Derivative Instruments, Gain (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive income on terminated derivative instruments	$ 427,000
Fair value hedging | Interest rate swap terminated
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivative_instruments	1
Designated as hedging instrument | Cash flow hedging
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 869,643,000
Designated as hedging instrument | Cash flow hedging | Interest rate swaps | Cash flow hedge of variable rate deposits
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivative_instruments	3
Designated as hedging instrument | Cash flow hedging | Interest rate collar | Cash flow hedge of variable rate deposits
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivative_instruments	1
Designated as hedging instrument | Fair value hedging | Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivative_instruments	15
Notional amount	$ 173,000,000
Designated as hedging instrument | Fair value hedging | Interest rate swaps effective starting after December 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Number of derivative instruments held | derivative_instruments	3
Notional amount	$ 55,900,000
Not designed as hedging instrument | Interest rate derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 6,100,000,000

Fair Value of Assets and Liab_3

Fair Value of Assets and Liabilities (Summary of Balances of Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 2,126,081	$ 1,803,666
Trading account securities	1,692	995
Equity securities with readily determinable fair value	34,717	0
Mortgage loans held-for-sale	264,070	313,592
Mortgage servicing rights	75,183	33,676	$ 19,103	$ 9,092
U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	126,404	143,822
U.S. Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	140,307	156,915
Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	138,490	115,352
Equity securities with readily determinable fair value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	36,802
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities	1,692	995
Mortgage loans held-for-sale	264,070	313,592
Loans held-for-investment	93,857	33,717
Mortgage servicing rights	75,183	33,676
Nonqualified deferred compensations assets	11,282	11,065
Derivative assets	73,172	52,069
Total financial assets	2,680,054	2,248,780
Derivative Liabilities	68,088	35,671
Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total financial assets	126,404	143,822
Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities	1,692	995
Mortgage loans held-for-sale	264,070	313,592
Loans held-for-investment	82,510	0
Mortgage servicing rights	0	0
Nonqualified deferred compensations assets	11,282	11,065
Derivative assets	70,715	49,912
Total financial assets	2,352,587	1,954,448
Derivative Liabilities	68,088	35,671
Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities	0	0
Mortgage loans held-for-sale	0	0
Loans held-for-investment	11,347	33,717
Mortgage servicing rights	75,183	33,676
Nonqualified deferred compensations assets	0	0
Derivative assets	2,457	2,157
Total financial assets	201,063	150,510
Derivative Liabilities	0	0
Fair Value, Measurements, Recurring | U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	126,404	143,822
Fair Value, Measurements, Recurring | U.S. Treasury | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	126,404	143,822
Fair Value, Measurements, Recurring | U.S. Treasury | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring | U.S. Treasury | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring | U.S. Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	140,307	156,915
Fair Value, Measurements, Recurring | U.S. Government agencies | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	137,157	153,136
Fair Value, Measurements, Recurring | U.S. Government agencies | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	3,150	3,779
Fair Value, Measurements, Recurring | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	138,490	115,352
Fair Value, Measurements, Recurring | Municipal | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	29,564	38,171
Fair Value, Measurements, Recurring | Municipal | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	108,926	77,181
Fair Value, Measurements, Recurring | Corporate notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	91,045	31,050
Fair Value, Measurements, Recurring | Corporate notes | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	91,045	31,050
Fair Value, Measurements, Recurring | Corporate notes | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring | Mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	1,629,835	1,319,725
Fair Value, Measurements, Recurring | Mortgage-backed | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	1,629,835	1,319,725
Fair Value, Measurements, Recurring | Mortgage-backed | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring | Equity securities with readily determinable fair value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		36,802
Equity securities with readily determinable fair value	34,717
Fair Value, Measurements, Recurring | Equity securities with readily determinable fair value | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		36,802
Equity securities with readily determinable fair value	34,717
Fair Value, Measurements, Recurring | Equity securities with readily determinable fair value | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		$ 0
Equity securities with readily determinable fair value	$ 0

Fair Value of Assets and Liab_4

Fair Value of Assets and Liabilities (Summary of Changes in Level Three Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Loans Held For Investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 33,717	$ 22,137
Total net gains (losses) included in Net income	(1,077)	1,025
Total net gains (losses) included in Other comprehensive income	0	0
Issuances	0
Sales	0
Settlements	(28,367)	(13,219)
Net transfers into/(out of) Level 3	7,074	23,774
Ending Balance	11,347	33,717
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	33,676	19,103
Total net gains (losses) included in Net income	27,701	14,573
Purchases	13,806
Issuances	0
Sales	0
Ending Balance	75,183	33,676
Derivative Financial Instruments, Assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	2,157	2,291
Total net gains (losses) included in Net income	300	(134)
Total net gains (losses) included in Other comprehensive income	0
Issuances	0
Sales	0
Ending Balance	2,457	2,157
Municipal
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	77,181	79,626
Total net gains (losses) included in Other comprehensive income	(8,541)	(501)
Purchases	63,644	33,593
Issuances	0
Sales	0
Settlements	(23,358)	(35,537)
Ending Balance	108,926	77,181
U.S. Government agencies
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	3,779	0
Total net gains (losses) included in Other comprehensive income	(314)	(504)
Issuances	0
Sales	0
Settlements	(315)
Net transfers into/(out of) Level 3		4,283
Ending Balance	$ 3,150	$ 3,779

Fair Value of Assets and Liab_5

Fair Value of Assets and Liabilities (Summary of Assets Measured at Fair Value on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans-collateral based	$ 127,269	$ 105,088
Impaired loans, fair value losses (gains) recognized	18,721
Real estate acquired through foreclosure fair value losses recognized	5,965
Fair value losses (gains) recognized	24,686
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans-collateral based	127,300
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans-collateral based	99,803
Other real estate owned	24,820
Total financial assets	124,623
Fair Value, Measurements, Nonrecurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans-collateral based	0
Other real estate owned	0
Total financial assets	0
Fair Value, Measurements, Nonrecurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans-collateral based	0
Other real estate owned	0
Total financial assets	0
Fair Value, Measurements, Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans-collateral based	99,803
Other real estate owned	24,820
Total financial assets	$ 124,623

Fair Value of Assets and Liab_6

Fair Value of Assets and Liabilities (Schedule of Valuation Techniques and Significant Unobservable Inputs Used to Measure Both Recurring and Nonrecurring) (Details) $ in Thousands	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 2,126,081	$ 1,803,666
Mortgage servicing rights	75,183	33,676	$ 19,103	$ 9,092
Impaired loans-collateral based	127,269	105,088
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans-collateral based	127,300
Fair Value, Measurements, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment	93,857	33,717
Mortgage servicing rights	75,183	33,676
Derivatives	73,172	52,069
Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment	11,347	33,717
Mortgage servicing rights	75,183	33,676
Derivatives	2,457	2,157
Fair Value, Measurements, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans-collateral based	99,803
Other real estate owned, including covered other real-estate owned	24,820
Fair Value, Measurements, Nonrecurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans-collateral based	99,803
Other real estate owned, including covered other real-estate owned	24,820
Municipal
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	138,490	115,352
Municipal | Fair Value, Measurements, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	138,490	115,352
Municipal | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	108,926	77,181
U.S. Government agencies
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	140,307	156,915
U.S. Government agencies | Fair Value, Measurements, Recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	140,307	156,915
U.S. Government agencies | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available-for-sale securities	$ 3,150	$ 3,779
Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.06
Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.18
Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.0998
Discount rate | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.04
Discount rate | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.05
Discount rate | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0431
Discount rate | Discounted cash flows | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.04
Mortgage servicing rights, measurement input	0.06
Discount rate | Discounted cash flows | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.05
Mortgage servicing rights, measurement input	0.18
Discount rate | Discounted cash flows | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0431
Mortgage servicing rights, measurement input	0.0998
Credit spread | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0
Credit spread | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.07
Credit spread | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0130
Credit spread | Discounted cash flows | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0
Credit spread | Discounted cash flows | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.07
Credit spread | Discounted cash flows | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.0130
Constant prepayment rate (CPR) | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.1206
Constant prepayment rate (CPR) | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.06
Constant prepayment rate (CPR) | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.91
Constant prepayment rate (CPR) | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.1176
Constant prepayment rate (CPR) | Discounted cash flows | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.1206
Constant prepayment rate (CPR) | Discounted cash flows | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.06
Constant prepayment rate (CPR) | Discounted cash flows | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	0.91
Constant prepayment rate (CPR) | Discounted cash flows | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans held-for-investment, measurement input	0.1206
Mortgage servicing rights, measurement input	0.1176
Cost of servicing | Discounted cash flows | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	15
Cost of servicing | Discounted cash flows | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	200
Cost of servicing | Discounted cash flows | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	77
Cost of servicing - delinquent | Discounted cash flows | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	200
Cost of servicing - delinquent | Discounted cash flows | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	1,000
Cost of servicing - delinquent | Discounted cash flows | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights, measurement input	273
Pull-through rate | Discounted cash flows | Minimum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivatives, measurement input	0.17
Pull-through rate | Discounted cash flows | Maximum | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivatives, measurement input	1
Pull-through rate | Discounted cash flows | Weighted Average | Fair Value, Measurements, Recurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivatives, measurement input	0.8615
Appraisal adjustment - cost of sale | Appraisal value | Fair Value, Measurements, Nonrecurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans - collateral based, measurement input	0.10
Other real estate owned, including covered other real-estate owned, measurement input	0.10
Appraisal adjustment - cost of sale | Appraisal value | Weighted Average | Fair Value, Measurements, Nonrecurring | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans - collateral based, measurement input	0.1000
Other real estate owned, including covered other real-estate owned, measurement input	0.1000

Fair Value of Assets and Liab_7

Fair Value of Assets and Liabilities (Summary of Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest bearing deposits with banks	$ 1,099,594	$ 1,063,242
Available-for-sale securities	2,126,081	1,803,666
Held-to-maturity securities	1,067,439	826,449
Trading account securities	1,692	995
Equity securities with readily determinable fair value	34,717	0
FHLB and FRB stock, at cost	91,354	89,989
Brokerage customer receivables	12,609	26,431
Mortgage loans held-for-sale	264,070	313,592
Mortgage servicing rights	75,183	33,676	$ 19,103	$ 9,092
Accrued interest receivable and other	696,707	567,374
FHLB advances	426,326	559,663
Other borrowings	393,855	266,123
Subordinated notes	139,210	139,088
Junior subordinated debentures	253,566	253,566
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	392,200	277,591
Interest bearing deposits with banks	1,099,594	1,063,242
Available-for-sale securities	2,126,081	1,803,666
Held-to-maturity securities	1,067,439	826,449
Trading account securities	1,692	995
Equity securities with readily determinable fair value	34,717	0
FHLB and FRB stock, at cost	91,354	89,989
Brokerage customer receivables	12,609	26,431
Mortgage loans held-for-sale	264,070	313,592
Loans held-for-investment, at fair value	93,857	33,717
Loans held-for-investment, at amortized cost	23,726,834	21,607,080
Mortgage servicing rights	75,183	33,676
Nonqualified deferred compensations assets	11,282	11,065
Derivative assets	73,172	52,069
Accrued interest receivable and other	260,281	227,649
Total financial assets	29,330,365	26,367,211
Non-maturity deposits	20,833,837	18,775,977
Deposits with stated maturities	5,260,841	4,407,370
FHLB advances	426,326	559,663
Other borrowings	393,855	266,123
Subordinated notes	139,210	139,088
Junior subordinated debentures	253,566	253,566
Derivative Liabilities	68,088	35,671
Accrued interest payable	16,025	8,030
Total financial liabilities	27,391,748	24,445,488
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	392,200	277,591
Interest bearing deposits with banks	1,099,594	1,063,242
Available-for-sale securities	2,126,081	1,803,666
Held-to-maturity securities	1,036,096	812,516
Trading account securities	1,692	995
Equity securities with readily determinable fair value	34,717	0
FHLB and FRB stock, at cost	91,354	89,989
Brokerage customer receivables	12,609	26,431
Mortgage loans held-for-sale	264,070	313,592
Loans held-for-investment, at fair value	93,857	33,717
Loans held-for-investment, at amortized cost	23,780,739	21,768,978
Mortgage servicing rights	75,183	33,676
Nonqualified deferred compensations assets	11,282	11,065
Derivative assets	73,172	52,069
Accrued interest receivable and other	260,281	227,649
Total financial assets	29,352,927	26,515,176
Non-maturity deposits	20,833,837	18,775,977
Deposits with stated maturities	5,283,063	4,350,004
FHLB advances	429,830	544,750
Other borrowings	393,855	266,123
Subordinated notes	138,345	144,266
Junior subordinated debentures	263,846	264,696
Derivative Liabilities	68,088	35,671
Accrued interest payable	16,025	8,030
Total financial liabilities	$ 27,426,889	$ 24,389,517

Fair Value of Assets and Liab_8

Fair Value of Assets and Liabilities (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018USD ($)$ / Loan	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 2,126,081,000	$ 1,803,666,000
Mortgage servicing rights	75,183,000	33,676,000	$ 19,103,000	$ 9,092,000
Mortgage loans held-for-sale	264,070,000	313,592,000
Impaired loans	$ 127,269,000	105,088,000
Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pull through rate, derivatives (as a percent)	17.00%
Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pull through rate, derivatives (as a percent)	100.00%
Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pull through rate, derivatives (as a percent)	86.15%
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 2,126,081,000	1,803,666,000
Mortgage servicing rights	75,183,000	33,676,000
Principal amount outstanding on loans held-for-sale or securitization or asset-backed financing arrangement	253,700,000	299,500,000
Mortgage loans held-for-sale	264,070,000	313,592,000
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	127,300,000
Level 3 | Valued Using Discounted Cash Flow Model
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	27,500,000
Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	138,490,000	115,352,000
U.S. Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	140,307,000	156,915,000
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment	93,857,000	33,717,000
Mortgage servicing rights	75,183,000	33,676,000
Derivative Assets	73,172,000	52,069,000
Mortgage loans held-for-sale	264,070,000	313,592,000
Fair Value, Measurements, Recurring | Non-performing
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held-for-sale	1,900,000	0
Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment	11,347,000	33,717,000
Mortgage servicing rights	75,183,000	33,676,000
Derivative Assets	2,457,000	2,157,000
Mortgage loans held-for-sale	$ 0	0
Fair Value, Measurements, Recurring | Level 3 | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, measurement input	0.06
Fair Value, Measurements, Recurring | Level 3 | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, measurement input	0.18
Fair Value, Measurements, Recurring | Level 3 | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, measurement input	0.0998
Fair Value, Measurements, Recurring | Level 3 | Mortgage Servicing Rights | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost of servicing loan (in dollars per loan) | $ / Loan	77
Cost of servicing delinquent loan (in dollars per loan) | $ / Loan	273
Fair Value, Measurements, Recurring | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 138,490,000	115,352,000
Fair Value, Measurements, Recurring | Municipal | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	108,926,000	77,181,000
Fair Value, Measurements, Recurring | U.S. Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	140,307,000	156,915,000
Fair Value, Measurements, Recurring | U.S. Government agencies | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	3,150,000	$ 3,779,000
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	99,803,000
Other real estate owned	24,820,000
Fair Value, Measurements, Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	99,803,000
Other real estate owned	$ 24,820,000
Discount rate | Fair Value, Measurements, Recurring | Level 3 | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment, measurement input	0.04
Discount rate | Fair Value, Measurements, Recurring | Level 3 | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment, measurement input	0.05
Discount rate | Fair Value, Measurements, Recurring | Level 3 | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment, measurement input	0.0431
Constant prepayment rate (CPR) | Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment, measurement input	0.1206
Constant prepayment rate (CPR) | Fair Value, Measurements, Recurring | Level 3 | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, measurement input	0.06
Constant prepayment rate (CPR) | Fair Value, Measurements, Recurring | Level 3 | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, measurement input	0.91
Constant prepayment rate (CPR) | Fair Value, Measurements, Recurring | Level 3 | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, measurement input	0.1176
Credit spread | Fair Value, Measurements, Recurring | Level 3 | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment, measurement input	0
Credit spread | Fair Value, Measurements, Recurring | Level 3 | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment, measurement input	0.07
Credit spread | Fair Value, Measurements, Recurring | Level 3 | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-investment, measurement input	0.0130
Appraisal value | Appraisal adjustment - cost of sale | Fair Value, Measurements, Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned, including covered other real-estate owned, measurement input	0.10
Appraisal value | Appraisal adjustment - cost of sale | Fair Value, Measurements, Nonrecurring | Level 3 | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned, including covered other real-estate owned, measurement input	0.1000

Shareholders' Equity (Summary o

Shareholders' Equity (Summary of the Company's Common and Preferred Stock) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Common Stock:
Shares authorized (in shares)	100,000,000	100,000,000
Shares issued (in shares)	56,518,119	56,068,220
Preferred Stock:
Shares authorized (in shares)	20,000,000	20,000,000
Common stock
Common Stock:
Shares authorized (in shares)	100,000,000	100,000,000
Shares issued (in shares)	56,518,119	56,068,220
Shares outstanding (in shares)	56,407,558	55,965,207
Cash dividend per share (in usd per share)	$ 0.76	$ 0.56
Preferred stock
Preferred Stock:
Shares authorized (in shares)	20,000,000	20,000,000
Shares issued (in shares)	5,000,000	5,000,000
Shares outstanding (in shares)	5,000,000	5,000,000

Shareholders' Equity (Component

Shareholders' Equity (Components of Other Comprehensive Income (Loss), Including the Related Income Tax Effects) (Details) - USD ($) $ in Thousands	Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	$ 2,976,939	$ 2,976,939	$ 2,695,617	$ 2,352,274
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	(2,974)
Other comprehensive (loss) income during the period, net of tax, before reclassification		(24,746)	24,425	(10,433)
Amount reclassified from accumulated other comprehensive income into net income, net of tax		(5,372)	(38)	(2,747)
Amount reclassified from accumulated other comprehensive income related to amortization of unrealized (gains) losses on investment securities transferred to held-to-maturity from available-for-sale		(65)	(894)	10,560
Total other comprehensive (loss) income		(30,183)	23,493	(2,620)
Balance at end of period		3,267,570	2,976,939	2,695,617
Accumulated Unrealized Losses on Securities
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	(15,813)	(15,813)	(29,309)	(17,674)
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	(4,517)
Other comprehensive (loss) income during the period, net of tax, before reclassification		(20,054)	14,417	(17,554)
Amount reclassified from accumulated other comprehensive income into net income, net of tax		(24)	(27)	(4,641)
Amount reclassified from accumulated other comprehensive income related to amortization of unrealized (gains) losses on investment securities transferred to held-to-maturity from available-for-sale		(65)	(894)	10,560
Total other comprehensive (loss) income		(20,143)	13,496	(11,635)
Balance at end of period		(42,353)	(15,813)	(29,309)
Accumulated Unrealized Gains (Losses) on Derivative Instruments
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	7,164	7,164	4,165	(2,193)
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	1,543
Other comprehensive (loss) income during the period, net of tax, before reclassification		4,498	3,010	4,464
Amount reclassified from accumulated other comprehensive income into net income, net of tax		(5,348)	(11)	1,894
Amount reclassified from accumulated other comprehensive income related to amortization of unrealized (gains) losses on investment securities transferred to held-to-maturity from available-for-sale		0	0	0
Total other comprehensive (loss) income		(850)	2,999	6,358
Balance at end of period		7,857	7,164	4,165
Accumulated Foreign Currency Translation Adjustments
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	(33,186)	(33,186)	(40,184)	(42,841)
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	0
Other comprehensive (loss) income during the period, net of tax, before reclassification		(9,190)	6,998	2,657
Amount reclassified from accumulated other comprehensive income into net income, net of tax		0	0	0
Amount reclassified from accumulated other comprehensive income related to amortization of unrealized (gains) losses on investment securities transferred to held-to-maturity from available-for-sale		0	0	0
Total other comprehensive (loss) income		(9,190)	6,998	2,657
Balance at end of period		(42,376)	(33,186)	(40,184)
Total Accumulated Other Comprehensive Loss
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	(41,835)	(41,835)	(65,328)	(62,708)
Cumulative effect adjustment of stranded tax effects - ASU 2018-02	(2,974)
Balance at end of period		$ (76,872)	$ (41,835)	$ (65,328)
ASU 2016-01
Activity Accumulated Other Comprehensive Income [Roll Forward]
Cumulative effect adjustment from the adoption of ASUs	(1,880)
ASU 2016-01 | Accumulated Unrealized Losses on Securities
Activity Accumulated Other Comprehensive Income [Roll Forward]
Cumulative effect adjustment from the adoption of ASUs	(1,880)
ASU 2016-01 | Accumulated Unrealized Gains (Losses) on Derivative Instruments
Activity Accumulated Other Comprehensive Income [Roll Forward]
Cumulative effect adjustment from the adoption of ASUs	0
ASU 2016-01 | Accumulated Foreign Currency Translation Adjustments
Activity Accumulated Other Comprehensive Income [Roll Forward]
Cumulative effect adjustment from the adoption of ASUs	0
ASU 2016-01 | Total Accumulated Other Comprehensive Loss
Activity Accumulated Other Comprehensive Income [Roll Forward]
Cumulative effect adjustment from the adoption of ASUs	$ (1,880)

Shareholders' Equity (Reclassif

Shareholders' Equity (Reclassification from Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
(Losses) gains on investment securities, net	$ (2,649)	$ 90	$ 12	$ (351)	$ 14	$ 39	$ 47	$ (55)	$ (2,898)	$ 45	$ 7,645
Interest on deposits									166,553	83,326	58,409
Interest on other borrowings									8,599	5,370	4,355
Interest on junior subordinated debentures									11,222	9,782	9,503
Income before taxes	107,662	122,814	121,591	108,066	95,785	104,248	101,946	88,018	460,133	389,997	331,854
Income tax expense	28,005	30,866	32,011	26,085	27,004	38,622	37,049	29,640	116,967	132,315	124,979
Net income	$ 79,657	$ 91,948	$ 89,580	$ 81,981	$ 68,781	$ 65,626	$ 64,897	$ 58,378	343,166	257,682	$ 206,875
Reclassification out of Accumulated Other Comprehensive Income | Accumulated unrealized losses on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
(Losses) gains on investment securities, net									33	45
Income before taxes									33	45
Income tax expense									9	18
Net income									24	27
Reclassification out of Accumulated Other Comprehensive Income | Accumulated unrealized losses on derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest on deposits									(7,549)	(1,085)
Interest on other borrowings									236	0
Interest on junior subordinated debentures									0	1,066
Income before taxes									7,313	19
Income tax expense									1,965	8
Net income									$ 5,348	$ 11

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 27, 2017	Apr. 25, 2017	Dec. 19, 2008	Jan. 31, 2019	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2012	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Shareholders' Equity [Line Items]
Shares issued in public offering (in shares)					3,000,000
Proceeds from the issuance of common stock, net					$ 152,900											$ 0	$ 0	$ 152,911
Cash dividends declared per common share (in usd per share)								$ 0.19	$ 0.19	$ 0.19	$ 0.19	$ 0.14	$ 0.14	$ 0.14	$ 0.14	$ 0.76	$ 0.56	$ 0.48
Subsequent Event
Shareholders' Equity [Line Items]
Cash dividends declared per common share (in usd per share)				$ 0.25
Common stock dividends per share declared annualized (in usd per share)				$ 1
US Treasury
Shareholders' Equity [Line Items]
Warrants outstanding (in shares)			1,643,295
Warrant termination period			10 years
Warrants exercised (in shares)																22,952	318,491
Common stock, shares, issued from exercise of warrant shares (in shares)																16,571	219,372
Series C preferred stock
Shareholders' Equity [Line Items]
Shares issued (in shares)							126,500
Preferred stock, value, issued							$ 126,500
Preferred stock, dividend rate (as a percent)							5.00%
Preferred stock converted (in shares)	124,184	2,073																30
Convertible preferred stock, conversion rate	24.72
Series D preferred stock
Shareholders' Equity [Line Items]
Shares issued (in shares)						5,000,000		5,000,000				5,000,000				5,000,000	5,000,000
Preferred stock, value, issued						$ 125,000		$ 125,000				$ 125,000				$ 125,000	$ 125,000
Preferred stock, dividend rate (as a percent)						6.50%
London Interbank Offered Rate (LIBOR) | Series D preferred stock
Shareholders' Equity [Line Items]
Variable rate (as a percent)						4.06%
Common stock
Shareholders' Equity [Line Items]
Common stock issued in conversion (in shares)	3,069,828	51,244																729

Segment Information (Summary of

Segment Information (Summary of Certain Operating Information For Reportable Segments) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net interest income	$ 254,088	$ 247,563	$ 238,170	$ 225,082	$ 219,099	$ 215,988	$ 204,409	$ 192,580	$ 964,903	$ 832,076	$ 722,193
Provision for credit losses	10,401	11,042	5,043	8,346	7,772	7,896	8,891	5,209	34,832	29,768	34,084
Non-interest income									356,150	319,506	325,430
Non-interest expense	211,333	213,637	206,769	194,349	196,580	183,575	183,544	168,118	826,088	731,817	681,685
Income tax expense	28,005	30,866	32,011	26,085	27,004	38,622	37,049	29,640	116,967	132,315	124,979
Net income	79,657	$ 91,948	$ 89,580	$ 81,981	68,781	$ 65,626	$ 64,897	$ 58,378	343,166	257,682	206,875
Total assets at end of year	31,244,849				27,915,970				31,244,849	27,915,970	25,668,553
Operating Segments
Segment Reporting Information [Line Items]
Net interest income									946,274	814,720	705,706
Provision for credit losses									34,832	29,768	34,084
Non-interest income									396,462	356,071	358,598
Non-interest expense									847,771	751,026	698,366
Income tax expense									116,967	132,315	124,979
Net income									343,166	257,682	206,875
Total assets at end of year	31,244,849				27,915,970				31,244,849	27,915,970	25,668,553
Operating Segments | Community Banking
Segment Reporting Information [Line Items]
Net interest income									791,838	677,481	588,847
Provision for credit losses									28,586	27,059	30,862
Non-interest income									238,668	211,354	230,414
Non-interest expense									681,749	599,455	556,798
Income tax expense									79,361	87,486	86,933
Net income									240,810	174,835	144,668
Total assets at end of year	25,438,454				22,781,923				25,438,454	22,781,923	21,172,080
Operating Segments | Specialty Finance
Segment Reporting Information [Line Items]
Net interest income									136,981	118,320	98,248
Provision for credit losses									6,246	2,709	3,222
Non-interest income									65,898	60,405	49,706
Non-interest expense									84,248	74,559	66,460
Income tax expense									30,325	35,775	29,512
Net income									82,060	65,682	48,760
Total assets at end of year	5,073,011				4,515,766				5,073,011	4,515,766	3,884,373
Operating Segments | Wealth Management
Segment Reporting Information [Line Items]
Net interest income									17,455	18,919	18,611
Provision for credit losses									0	0	0
Non-interest income									91,896	84,312	78,478
Non-interest expense									81,774	77,012	75,108
Income tax expense									7,281	9,054	8,534
Net income									20,296	17,165	13,447
Total assets at end of year	733,384				618,281				733,384	618,281	612,100
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net interest income									18,629	17,356	16,487
Provision for credit losses									0	0	0
Non-interest income									(40,312)	(36,565)	(33,168)
Non-interest expense									(21,683)	(19,209)	(16,681)
Income tax expense									0	0	0
Net income									0	0	0
Total assets at end of year	$ 0				$ 0				$ 0	$ 0	$ 0

Segment Information (Narrative)

Segment Information (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018subsidiarysegment
Segment Reporting Information [Line Items]
Number of reportable segments	3
Number of bank subsidiaries that management monitors | subsidiary	15
Community Banking | Operating Segments
Segment Reporting Information [Line Items]
Number of reportable segments	1

Condensed Parent Company Fina_3

Condensed Parent Company Financial Statements (Statements of Financial Condition) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets
Cash	$ 392,142	$ 277,534
Loans, net of unearned income	23,820,691	21,640,797
Allowance for loan losses	152,770	137,905	$ 122,291
Net loans	23,667,921	21,502,892
Goodwill	573,141	501,884
Total assets	31,244,849	27,915,970	25,668,553
Liabilities and Shareholders’ Equity
Subordinated notes	139,210	139,088
Other borrowings	393,855	266,123
Junior subordinated debentures	253,566	253,566
Shareholders’ equity	3,267,570	2,976,939	$ 2,695,617	$ 2,352,274
Total liabilities and shareholders’ equity	31,244,849	27,915,970
Reportable Legal Entities | Parent Company
Assets
Cash	37,931	78,045
Available-for-sale debt securities and equity securities with readily determinable fair value	12,765	14,461
Investment in and receivable from subsidiaries	3,660,968	3,249,202
Loans, net of unearned income	1,200	1,845
Allowance for loan losses	0	0
Net loans	1,200	1,845
Goodwill	8,371	8,371
Other assets	206,902	174,781
Total assets	3,928,137	3,526,705
Liabilities and Shareholders’ Equity
Other liabilities	75,609	66,909
Subordinated notes	139,210	139,088
Other borrowings	192,182	90,203
Junior subordinated debentures	253,566	253,566
Shareholders’ equity	3,267,570	2,976,939
Total liabilities and shareholders’ equity	$ 3,928,137	$ 3,526,705

Condensed Parent Company Fina_4

Condensed Parent Company Financial Statements (Statements Of Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Expenses
Interest expense	$ 66,508	$ 57,399	$ 45,877	$ 36,123	$ 32,741	$ 31,700	$ 26,772	$ 23,179	$ 205,907	$ 114,392	$ 90,264
Salaries and employee benefits									480,077	430,078	405,158
(Loss) income before income taxes and equity in undistributed income of subsidiaries	107,662	122,814	121,591	108,066	95,785	104,248	101,946	88,018	460,133	389,997	331,854
Income tax benefit	(28,005)	(30,866)	(32,011)	(26,085)	(27,004)	(38,622)	(37,049)	(29,640)	(116,967)	(132,315)	(124,979)
Net income	$ 79,657	$ 91,948	$ 89,580	$ 81,981	$ 68,781	$ 65,626	$ 64,897	$ 58,378	343,166	257,682	206,875
Reportable Legal Entities | Parent Company
Income
Dividends and other revenue from subsidiaries									171,388	155,969	89,184
Other income									4	2,488	4,344
Total income									171,392	158,457	93,528
Expenses
Interest expense									22,375	19,207	18,498
Salaries and employee benefits									64,726	50,683	34,299
Other expenses									108,038	74,618	62,778
Total expenses									195,139	144,508	115,575
(Loss) income before income taxes and equity in undistributed income of subsidiaries									(23,747)	13,949	(22,047)
Income tax benefit									34,186	47,139	31,061
Income before equity in undistributed net income of subsidiaries									10,439	61,088	9,014
Equity in undistributed net income of subsidiaries									332,727	196,594	197,861
Net income									$ 343,166	$ 257,682	$ 206,875

Condensed Parent Company Fina_5

Condensed Parent Company Financial Statements (Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Jun. 30, 2016	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Activities:
Net income		$ 79,657	$ 91,948	$ 89,580	$ 81,981	$ 68,781	$ 65,626	$ 64,897	$ 58,378	$ 343,166	$ 257,682	$ 206,875
Adjustments to reconcile net income to net cash provided by (used for) operating activities
Provision for credit losses		10,401	$ 11,042	$ 5,043	8,346	7,772	$ 7,896	$ 8,891	5,209	34,832	29,768	34,084
Gain on early extinguishment of debt										0	0	(3,588)
Depreciation and amortization										67,665	63,107	53,148
Deferred income tax expense (benefit)										55,224	63,243	6,676
Stock-based compensation expense										13,496	12,858	9,303
Decrease (increase) in other assets										(133,519)	(126,583)	(43,953)
Increase in other liabilities										(27,001)	31,790	114,531
Net Cash Provided by Operating Activities										377,182	401,626	310,966
Investing Activities:
Net cash paid for acquisitions, net										(53,871)	(284)	(613,619)
Net Cash Used for Investing Activities										(2,763,498)	(2,303,232)	(2,492,326)
Financing Activities:
Increase (decrease) in subordinated notes, other borrowings and junior subordinated debentures, net										137,257	(4,888)	(3,405)
Proceeds from the issuance of common stock, net	$ 152,900									0	0	152,911
Issuance of common shares resulting from exercise of stock options, employee stock purchase plan and conversion of common stock warrants										15,903	28,229	15,828
Dividends paid										(50,987)	(40,543)	(38,568)
Common stock repurchases for tax withholdings related to stock-based compensation										(648)	(397)	(616)
Net Cash Provided by Financing Activities										2,500,925	1,909,152	2,175,610
Net Increase (Decrease) in Cash and Cash Equivalents										114,609	7,546	(5,750)
Cash and Cash Equivalents at Beginning of Period					277,591				270,045	277,591	270,045	275,795
Cash and Cash Equivalents at End of Period		392,200				277,591				392,200	277,591	270,045
Reportable Legal Entities | Parent Company
Operating Activities:
Net income										343,166	257,682	206,875
Adjustments to reconcile net income to net cash provided by (used for) operating activities
Provision for credit losses										56	0	0
Gain on early extinguishment of debt										0	0	(4,305)
Depreciation and amortization										11,943	10,783	10,400
Deferred income tax expense (benefit)										502	2,809	(601)
Stock-based compensation expense										6,025	5,185	3,762
Decrease (increase) in other assets										3,685	1,956	(319)
Increase in other liabilities										650	9,967	9,618
Equity in undistributed net income of subsidiaries										(332,727)	(196,594)	(197,861)
Net Cash Provided by Operating Activities										33,300	91,788	27,569
Investing Activities:
Capital distributions from (contributions to) subsidiaries, net										4,632	(42,736)	(118,575)
Net cash paid for acquisitions, net										(87,081)	0	(61,308)
Other investing activity, net										(57,143)	(28,132)	(18,051)
Net Cash Used for Investing Activities										(139,592)	(70,868)	(197,934)
Financing Activities:
Increase (decrease) in subordinated notes, other borrowings and junior subordinated debentures, net										101,910	20,008	(26,251)
Proceeds from the issuance of common stock, net										0	0	152,911
Issuance of common shares resulting from exercise of stock options, employee stock purchase plan and conversion of common stock warrants										15,903	28,229	15,828
Dividends paid										(50,987)	(40,543)	(38,568)
Common stock repurchases for tax withholdings related to stock-based compensation										(648)	(397)	(616)
Net Cash Provided by Financing Activities										66,178	7,297	103,304
Net Increase (Decrease) in Cash and Cash Equivalents										(40,114)	28,217	(67,061)
Cash and Cash Equivalents at Beginning of Period					$ 78,045				$ 49,828	78,045	49,828	116,889
Cash and Cash Equivalents at End of Period		$ 37,931				$ 78,045				$ 37,931	$ 78,045	$ 49,828

Earnings Per Share (Computation

Earnings Per Share (Computation Of Basic And Diluted Earnings Per Common Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income	$ 79,657	$ 91,948	$ 89,580	$ 81,981	$ 68,781	$ 65,626	$ 64,897	$ 58,378	$ 343,166	$ 257,682	$ 206,875
Less: Preferred stock dividends	2,050	2,050	2,050	2,050	2,050	2,050	2,050	3,628	8,200	9,778	14,513
Net income applicable to common shares	$ 77,607	$ 89,898	$ 87,530	$ 79,931	$ 66,731	$ 63,576	$ 62,847	$ 54,750	334,966	247,904	192,362
Add: Dividends on convertible preferred stock, if dilutive									0	1,578	6,313
Net income applicable to common shares—Diluted									$ 334,966	$ 249,482	$ 198,675
Weighted average common shares outstanding (in shares)									56,300	54,703	50,278
Common stock equivalents (in shares)									908	998	894
Convertible preferred stock, if dilutive (in shares)									0	985	3,100
Total dilutive potential common shares (in shares)									908	1,983	3,994
Weighted average common shares and effect of dilutive potential common shares (in shares)									57,208	56,686	54,272
Net income per common share:
Basic (usd per share)	$ 1.38	$ 1.59	$ 1.55	$ 1.42	$ 1.19	$ 1.14	$ 1.15	$ 1.05	$ 5.95	$ 4.53	$ 3.83
Diluted (usd per share)	$ 1.35	$ 1.57	$ 1.53	$ 1.40	$ 1.17	$ 1.12	$ 1.11	$ 1	$ 5.86	$ 4.40	$ 3.66

Quarterly Financial Summary (_3

Quarterly Financial Summary (Unaudited) (Summary Of Quarterly Financial Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Interest income	$ 320,596	$ 304,962	$ 284,047	$ 261,205	$ 251,840	$ 247,688	$ 231,181	$ 215,759	$ 1,170,810	$ 946,468	$ 812,457
Interest expense	66,508	57,399	45,877	36,123	32,741	31,700	26,772	23,179	205,907	114,392	90,264
Net interest income	254,088	247,563	238,170	225,082	219,099	215,988	204,409	192,580	964,903	832,076	722,193
Provision for credit losses	10,401	11,042	5,043	8,346	7,772	7,896	8,891	5,209	34,832	29,768	34,084
Net interest income after provision for credit losses	243,687	236,521	233,127	216,736	211,327	208,092	195,518	187,371	930,071	802,308	688,109
Non-interest income, excluding net securities gains (losses)	77,957	99,840	95,221	86,030	81,024	79,692	89,925	68,820
(Losses) gains on investment securities, net	(2,649)	90	12	(351)	14	39	47	(55)	(2,898)	45	7,645
Non-interest expense	211,333	213,637	206,769	194,349	196,580	183,575	183,544	168,118	826,088	731,817	681,685
Income before taxes	107,662	122,814	121,591	108,066	95,785	104,248	101,946	88,018	460,133	389,997	331,854
Income tax expense	28,005	30,866	32,011	26,085	27,004	38,622	37,049	29,640	116,967	132,315	124,979
Net income	79,657	91,948	89,580	81,981	68,781	65,626	64,897	58,378	343,166	257,682	206,875
Preferred stock dividends	2,050	2,050	2,050	2,050	2,050	2,050	2,050	3,628	8,200	9,778	14,513
Net income applicable to common shares	$ 77,607	$ 89,898	$ 87,530	$ 79,931	$ 66,731	$ 63,576	$ 62,847	$ 54,750	$ 334,966	$ 247,904	$ 192,362
Net income per common share:
Basic (usd per share)	$ 1.38	$ 1.59	$ 1.55	$ 1.42	$ 1.19	$ 1.14	$ 1.15	$ 1.05	$ 5.95	$ 4.53	$ 3.83
Diluted (usd per share)	1.35	1.57	1.53	1.40	1.17	1.12	1.11	1	5.86	4.40	3.66
Cash dividends declared per common share (in usd per share)	$ 0.19	$ 0.19	$ 0.19	$ 0.19	$ 0.14	$ 0.14	$ 0.14	$ 0.14	$ 0.76	$ 0.56	$ 0.48

Subsequent Events (Details)

Subsequent Events (Details) $ in Thousands, $ in Millions	Feb. 15, 2019CAD ($)	Jun. 30, 2018CAD ($)	Dec. 31, 2017CAD ($)	Dec. 31, 2015CAD ($)	Dec. 31, 2014CAD ($)	Dec. 31, 2015CAD ($)	Dec. 31, 2017CAD ($)	Jun. 30, 2018CAD ($)	Feb. 15, 2019CAD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Subsequent Event [Line Items]
Assets										$ 31,244,849	$ 27,915,970	$ 25,668,553
Loans										23,667,921	21,502,892
Deposits										26,094,678	$ 23,183,347
Receivables Purchase Agreement
Subsequent Event [Line Items]
Proceeds from issuance of debt		$ 20	$ 10	$ 10	$ 150	$ 160	$ 170	$ 190
Subsequent Event | Receivables Purchase Agreement
Subsequent Event [Line Items]
Proceeds from issuance of debt	$ 20								$ 210
Oak Bank
Subsequent Event [Line Items]
Assets										196,000
Loans										143,000
Deposits										$ 158,000