Wintrust Financial (WTFC) 10-Q 9 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 31, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Entity Current Reporting Status	Yes
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 Common Stock, Shares Outstanding		48,367,147

Consolidated Statements Of Cond

Consolidated Statements Of Condition - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Assets
Cash and due from banks	$ 247,341	$ 225,136	$ 260,694
Federal funds sold and securities purchased under resale agreements	3,314	5,571	26,722
Interest bearing deposits with banks	701,106	998,437	620,370
Available-for-sale securities, at fair value	2,214,281	1,792,078	1,782,648
Trading account securities	3,312	1,206	6,015
Federal Home Loan Bank and Federal Reserve Bank stock	90,308	91,582	80,951
Brokerage customer receivables	28,293	24,221	26,624
Mortgage loans held-for-sale, at fair value	347,005	351,290	363,303
Loans, net of unearned income, excluding covered loans	16,316,211	14,409,398	14,052,059
Covered loans	168,609	226,709	254,605
Total loans	16,484,820	14,636,107	14,306,664
Less: Allowance for loan losses	102,996	91,705	91,019
Less: Allowance for covered loan losses	2,918	2,131	2,655
Net loans	16,378,906	14,542,271	14,212,990
Premises and equipment, net	587,348	555,228	555,241
FDIC indemnification asset	0	11,846	27,359
Accrued interest receivable and other assets	667,036	501,882	494,213
Trade date securities receivable	277,981	485,534	285,627
Goodwill	472,166	405,634	406,604
Other intangible assets	25,533	18,811	19,984
Total assets	22,043,930	20,010,727	19,169,345
Deposits:
Non-interest bearing	4,705,994	3,518,685	3,253,477
Interest bearing	13,522,475	12,763,159	12,811,769
Total deposits	18,228,469	16,281,844	16,065,246
Federal Home Loan Bank advances	451,330	733,050	347,500
Other borrowings	259,978	196,465	51,483
Subordinated notes	140,000	140,000	140,000
Junior subordinated debentures	268,566	249,493	249,493
Trade date securities payable	617	3,828	0
Accrued interest payable and other liabilities	359,234	336,225	287,115
Total liabilities	19,708,194	17,940,905	17,140,837
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 September 30, 2015, December 31, 2014, and September 30, 2014; 48,422,294 shares issued at September 30, 2015, 46,881,108 shares issued at December 31, 2014, and 46,766,420 shares issued at September 30, 2014	48,422	46,881	46,766
Surplus	1,187,407	1,133,955	1,129,975
Treasury stock, at cost, 85,424 shares at September 30, 2015, 76,053 shares at December 31, 2014, and 75,373 shares at September 30, 2014	(3,964)	(3,549)	(3,519)
Retained earnings	901,652	803,400	771,519
Accumulated other comprehensive loss	(49,093)	(37,332)	(42,700)
Total shareholders' equity	2,335,736	2,069,822	2,028,508
Total liabilities and shareholders' equity	22,043,930	20,010,727	19,169,345
Series C - $1,000 liquidation value; 126,312 shares issued and outstanding at September 30, 2015 and 126,467 shares issued and outstanding at December 31, 2014 and September 30, 2014
Preferred stock, no par value; 20,000,000 shares authorized:
Preferred stock, Series C and Series D	126,312	126,467	126,467
Series D - $25 liquidation value; 5,000,000 shares issued and outstanding at September 30, 2015 and no shares issued and outstanding at December 31, 2014 and September 30, 2014
Preferred stock, no par value; 20,000,000 shares authorized:
Preferred stock, Series C and Series D	$ 125,000	$ 0	$ 0

Consolidated Statements Of Con3

Consolidated Statements Of Condition (Parenthetical) - $ / shares	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Preferred stock, no par value
Preferred stock, 20,000,000 shares authorized	20,000,000	20,000,000	20,000,000
Common stock, no par value
Common stock, $1.00 stated value	$ 1	$ 1	$ 1
Common stock, 100,000,000 shares authorized	100,000,000	100,000,000	100,000,000
Common stock, shares issued	48,422,294	46,881,108	46,766,420
Treasury stock, shares	85,424	76,053	75,373
Series C - $1,000 liquidation value; 126,312 shares issued and outstanding at September 30, 2015 and 126,467 shares issued and outstanding at December 31, 2014 and September 30, 2014
Preferred stock, liquidation value per share	$ 1,000	$ 1,000	$ 1,000
Preferred stock, shares outstanding	126,312	126,467	126,467
Series D - $25 liquidation value; 5,000,000 shares issued and outstanding at September 30, 2015 and no shares issued and outstanding at December 31, 2014 and September 30, 2014
Preferred stock, liquidation value per share	$ 25	$ 0	$ 0
Preferred stock, shares outstanding	5,000,000	0	0

Consolidated Statements Of Inco

Consolidated Statements Of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Interest income
Interest and fees on loans	$ 167,831	$ 156,534	$ 482,330	$ 455,548
Interest bearing deposits with banks	372	409	993	977
Federal funds sold and securities purchased under resale agreements	1	12	4	22
Available-for-sale securities	16,130	12,767	44,601	39,190
Trading account securities	19	20	83	34
Federal Home Loan Bank and Federal Reserve Bank stock	821	733	2,375	2,171
Brokerage customer receivables	205	201	591	610
Total interest income	185,379	170,676	530,977	498,552
Interest expense
Interest on deposits	12,436	12,298	36,246	35,980
Interest on Federal Home Loan Bank advances	2,458	2,641	6,426	7,989
Interest on other borrowings	1,045	200	2,620	1,460
Interest on subordinated notes	1,776	1,776	5,328	2,130
Interest on junior subordinated debentures	2,124	2,091	6,034	6,137
Total interest expense	19,839	19,006	56,654	53,696
Net interest income	165,540	151,670	474,323	444,856
Provision for credit losses	8,322	5,864	23,883	14,404
Net interest income after provision for credit losses	157,218	145,806	450,440	430,452
Non-interest income
Wealth management	18,243	17,659	54,819	52,694
Mortgage banking	27,887	26,691	91,694	66,923
Service charges on deposit accounts	7,403	6,084	20,174	17,118
(Losses) gains on available-for-sale securities, net	(98)	(153)	402	(522)
Fees from covered call options	2,810	2,107	11,735	4,893
Trading (losses) gains, net	(135)	293	(452)	(1,102)
Other	8,843	5,271	28,135	17,579
Total non-interest income	64,953	57,952	206,507	157,583
Non-interest expense
Salaries and employee benefits	97,749	85,976	282,300	247,873
Equipment	8,887	7,570	24,637	22,196
Occupancy, net	12,066	10,446	35,818	31,289
Data processing	8,127	4,765	19,656	14,023
Advertising and marketing	6,237	3,528	16,550	9,902
Professional fees	4,100	4,035	13,838	11,535
Amortization of other intangible assets	1,350	1,202	3,297	3,521
FDIC insurance	3,035	3,211	9,069	9,358
OREO expense, net	(367)	581	1,885	7,047
Other	18,790	17,186	54,539	46,662
Total non-interest expense	159,974	138,500	461,589	403,406
Income before taxes	62,197	65,258	195,358	184,629
Income tax expense	23,842	25,034	74,120	71,364
Net income	38,355	40,224	121,238	113,265
Preferred stock dividends and discount accretion	4,079	1,581	7,240	4,743
Net income applicable to common shares	$ 34,276	$ 38,643	$ 113,998	$ 108,522
Net income per common share-Basic	$ 0.71	$ 0.83	$ 2.39	$ 2.34
Net income per common share-Diluted	0.69	0.79	2.29	2.23
Cash dividends declared per common share	$ 0.11	$ 0.10	$ 0.33	$ 0.30
Weighted average common shares outstanding	48,158	46,639	47,658	46,453
Dilutive potential common shares	4,049	4,241	4,141	4,349
Average common shares and dilutive common shares	52,207	50,880	51,799	50,802

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 38,355	$ 40,224	$ 121,238	$ 113,265
Unrealized gains on securities
Before tax	31,268	1,345	4,144	49,920
Tax effect	(12,273)	(533)	(1,645)	(19,669)
Net of tax	18,995	812	2,499	30,251
Less: Reclassification of net (losses) gains included in net income
Before tax	(98)	(153)	402	(522)
Tax effect	38	62	(158)	208
Net of tax	(60)	(91)	244	(314)
Net unrealized gains on securities	19,055	903	2,255	30,565
Unrealized gains (losses) on derivative instruments
Before tax	99	971	(247)	247
Tax effect	(39)	(386)	97	(98)
Net unrealized gains (losses) on derivative instruments	60	585	(150)	149
Foreign currency translation adjustment
Before tax	(8,682)	(13,062)	(18,900)	(13,976)
Tax effect	2,345	3,377	5,034	3,598
Net foreign currency translation adjustment	(6,337)	(9,685)	(13,866)	(10,378)
Total other comprehensive income (loss)	12,778	(8,197)	(11,761)	20,336
Comprehensive income	$ 51,133	$ 32,027	$ 109,477	$ 133,601

Consolidated Statements Of Chan

Consolidated Statements Of Changes In Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Preferred stock	Common stock	Surplus	Treasury stock	Retained earnings	Accumulated other comprehensive loss
Balance at Dec. 31, 2013	$ 1,900,589	$ 126,477	$ 46,181	$ 1,117,032	$ (3,000)	$ 676,935	$ (63,036)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	113,265					113,265
Other comprehensive income (loss), net of tax	20,336						20,336
Cash dividends declared on common stock	(13,938)					(13,938)
Dividends on preferred stock	(4,743)					(4,743)
Stock-based compensation	5,754			5,754	0
Conversion of Series C preferred stock to common stock	0	(10)	1	9
Common stock issued for:
Exercise of stock options and warrants	3,934		450	3,797	(313)
Restricted stock awards	12		67	151	(206)
Employee stock purchase plan	2,133		47	2,086
Director compensation plan	1,166		20	1,146
Balance at Sep. 30, 2014	2,028,508	126,467	46,766	1,129,975	(3,519)	771,519	(42,700)
Balance at Dec. 31, 2014	2,069,822	126,467	46,881	1,133,955	(3,549)	803,400	(37,332)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	121,238					121,238	0
Other comprehensive income (loss), net of tax	(11,761)						(11,761)
Cash dividends declared on common stock	(15,746)					(15,746)
Dividends on preferred stock	(7,240)					(7,240)
Stock-based compensation	7,817			7,817
Issuance of Series D preferred stock	120,842	125,000	0	(4,158)	0	0	0
Conversion of Series C preferred stock to common stock	0	(155)	4	151
Common stock issued for:
Acquisitions	38,723		811	37,912	0
Exercise of stock options and warrants	8,575		564	8,141	(130)
Restricted stock awards	196		99	382	(285)
Employee stock purchase plan	2,040		43	1,997
Director compensation plan	1,230		20	1,210
Balance at Sep. 30, 2015	$ 2,335,736	$ 251,312	$ 48,422	$ 1,187,407	$ (3,964)	$ 901,652	$ (49,093)

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating Activities:
Net income	$ 121,238	$ 113,265
Adjustments to reconcile net income to net cash provided by operating activities
Provision for credit losses	23,883	14,404
Depreciation and amortization	24,975	23,952
Stock-based compensation expense	7,817	5,754
Excess tax benefits from stock-based compensation arrangements	(660)	(339)
Net amortization of premium on securities	2,576	4,733
Mortgage servicing rights fair value change, net	641	706
Originations and purchases of mortgage loans held-for-sale	(3,094,901)	(2,272,919)
Proceeds from sales of mortgage loans held-for-sale	3,182,623	2,299,103
Bank owned life insurance, net of claims	(1,683)	(2,039)
Increase in trading securities, net	(2,106)	(5,518)
Net (increase) decrease in brokerage customer receivables	(4,072)	4,329
Gains on mortgage loans sold	(83,437)	(55,160)
(Gains) losses on available-for-sale securities, net	(402)	522
Losses on sales of premises and equipment, net	512	664
Net (gains) losses on sales and fair value adjustments of other real estate owned	(585)	2,628
(Increase) decrease in accrued interest receivable and other assets, net	(110,632)	82,159
Decrease in accrued interest payable and other liabilities, net	(28,717)	(55,874)
Net Cash Provided by Operating Activities	37,070	160,370
Investing Activities:
Proceeds from maturities of available-for-sale securities	397,832	222,434
Proceeds from sales of available-for-sale securities	1,216,860	578,594
Purchases of available-for-sale securities	(1,584,282)	(944,281)
Redemption (purchase) of Federal Home Loan Bank and Federal Reserve Bank stock, net	1,274	(1,690)
Net cash (paid) received for acquisitions	(15,428)	228,946
Proceeds from sales of other real estate owned	34,936	73,940
Proceeds received from the FDIC related to reimbursements on covered assets	1,697	17,652
Net decrease (increase) in interest bearing deposits with banks	438,072	(124,796)
Net increase in loans	(1,311,797)	(1,011,889)
Redemption of bank owned life insurance	2,701	0
Purchases of premises and equipment, net	(29,375)	(30,982)
Net Cash Used for Investing Activities	(847,510)	(992,072)
Financing Activities:
Increase in deposit accounts	970,090	1,000,603
Increase (decrease) in other borrowings, net	38,644	(203,621)
Decrease in Federal Home Loan Bank advances, net	(293,360)	(70,000)
Proceeds from the issuance of preferred stock, net	120,842	0
Proceeds from the issuance of subordinated notes, net	0	139,090
Excess tax benefits from stock-based compensation arrangements	660	339
Issuance of common shares resulting from the exercise of stock options and the employee stock purchase plan	14,413	8,043
Common stock repurchases	(415)	(519)
Dividends paid	(20,486)	(18,681)
Net Cash Provided by Financing Activities	830,388	855,254
Net Increase in Cash and Cash Equivalents	19,948	23,552
Cash and Cash Equivalents at Beginning of Period	230,707	263,864
Cash and Cash Equivalents at End of Period	$ 250,655	$ 287,416

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements of Wintrust Financial Corporation and Subsidiaries (“Wintrust” or “the Company”) presented herein are unaudited, but in the opinion of management reflect all necessary adjustments of a normal or recurring nature for a fair presentation of results as of the dates and for the periods covered by the consolidated financial statements. The accompanying consolidated financial statements are unaudited and do not include information or footnotes necessary for a complete presentation of financial condition, results of operations or cash flows in accordance with U.S. generally accepted accounting principles ("GAAP"). The consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014 (“ 2014 Form 10-K”). Operating results reported for the three-month and nine-month periods are not necessarily indicative of the results which may be expected for the entire year. Reclassifications of certain prior period amounts have been made to conform to the current period presentation. The preparation of the financial statements requires management to make estimates, assumptions and judgments that affect the reported amounts of assets and liabilities. Management believes that the estimates made are reasonable, however, changes in estimates may be required if economic or other conditions develop differently from management’s expectations. Certain policies and accounting principles inherently have a greater reliance on the use of estimates, assumptions and judgments and as such have a greater possibility of producing results that could be materially different than originally reported. Management views critical accounting policies to be those which are highly dependent on subjective or complex judgments, estimates and assumptions, and where changes in those estimates and assumptions could have a significant impact on the financial statements. Management currently views the determination of the allowance for loan losses, allowance for covered loan losses and the allowance for losses on lending-related commitments, loans acquired with evidence of credit quality deterioration since origination, estimations of fair value, the valuations required for impairment testing of goodwill, the valuation and accounting for derivative instruments and income taxes as the accounting areas that require the most subjective and complex judgments, and as such could be the most subject to revision as new information becomes available. Descriptions of our significant accounting policies are included in Note 1 - “Summary of Significant Accounting Policies” of the Company’s 2014 Form 10-K.

Recent Accounting Developments

Recent Accounting Developments	9 Months Ended
	Sep. 30, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Developments	Recent Accounting Developments Accounting for Investments in Qualified Affordable Housing Projects In January 2014, the FASB issued ASU No. 2014-01, “Investments - Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects,” to provide guidance on accounting for investments by a reporting entity in flow-through limited liability entities that invest in affordable housing projects that qualify for the low-income housing tax credit. This ASU permits a new accounting treatment, if certain conditions are met, which allows the Company to amortize the initial cost of an investment in proportion to the amount of tax credits and other tax benefits received with recognition of the investment performance in income tax expense. The Company adopted this new guidance beginning January 1, 2015. The guidance did not have a material impact on the Company's consolidated financial statements. Repossession of Residential Real Estate Collateral In January 2014, the FASB issued ASU No. 2014-04, “Receivables - Troubled Debt Restructurings by Creditors (Topic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure,” to address diversity in practice and clarify guidance regarding the accounting for an in-substance repossession or foreclosure of residential real estate collateral. This ASU clarifies that an in-substance repossession or foreclosure occurs upon either the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or the borrower conveying all interest in the residential real estate property to the creditor. Additionally, this ASU requires disclosure of both the amount of foreclosed residential real estate property held by the Company and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure. The Company adopted this new guidance beginning January 1, 2015. The guidance did not have a material impact on the Company's consolidated financial statements. 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 would result in the guidance becoming effective for fiscal years beginning after December 15, 2017. The Company is currently evaluating the impact of adopting this new guidance on the consolidated financial statements. Extraordinary and Unusual Items In January 2015, the FASB issued ASU No. 2015-01, “Income Statement - Extraordinary and Unusual Items (Subtopic 225-20): Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items,” to eliminate the concept of extraordinary items related to separately classifying, presenting and disclosing certain events and transactions that meet the criteria for that concept. This guidance is effective for fiscal years beginning after December 15, 2015 and is to be applied either prospectively or retrospectively. The Company does not expect this guidance to have a material impact on the Company’s consolidated financial statements. Consolidation In February 2015, the FASB issued ASU No. 2015-02, “Consolidation (Topic 810): Amendments to the Consolidation Analysis,” which changes the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. This guidance is effective for fiscal years beginning after December 15, 2015 and is to be applied retrospectively. The Company is currently evaluating the impact of adopting this new guidance on the consolidated financial statements. Debt Issuance Costs In April 2015, the FASB issued ASU No. 2015-03, "Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs," to clarify the presentation of debt issuance costs within the balance sheet. This ASU requires that an entity present debt issuance costs related to a recognized debt liability on the balance sheet as a direct deduction from the carrying amount of that debt liability, not as a separate asset. The ASU does not affect the current guidance for the recognition and measurement for these debt issuance costs. Additionally, in August 2015, the FASB issued ASU No. 2015-15, "Interest - Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements (Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting," to further clarify the the presentation of debt issuance costs related to line-of-credit agreements. This ASU states the SEC would not object to an entity deferring and presenting debt issuance costs related to line-of-credit agreements as an asset on the balance sheet and subsequently amortizing these costs ratably over the term of the agreement, regardless of any outstanding borrowing under the line-of-credit agreement. This guidance is effective for fiscal years beginning after December 15, 2015 and is to be applied retrospectively. The Company does not expect this guidance to have a material impact on the Company’s consolidated financial statements. Business Combinations In September 2015, the FASB issued ASU No. 2015-16, "Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments," to simplify the accounting for subsequent adjustments made to provisional amounts recognized at the acquisition date of a business combination. This ASU eliminates the requirement to retrospectively account for these adjustment for all prior periods impacted. The acquirer is required to recognize these adjustments identified during the measurement period in the reporting period in which the adjustment amount is determined. Additionally, the ASU requires an entity to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings that would have been recorded in previous reporting periods if the adjustment had been recognized at the acquisition date. This guidance is effective for fiscal years beginning after December 15, 2015 and is to be applied prospectively. The Company does not expect this guidance to have a material impact on the Company’s consolidated financial statements.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
Business Combinations	Business Combinations Non-FDIC Assisted Bank Acquisitions On July 24, 2015 , the Company acquired Community Financial Shares, Inc ("CFIS"). CFIS was the parent company of Community Bank - Wheaton/Glen Ellyn ("CBWGE"), which had four banking locations. CBWGE was merged into the Company's wholly-owned subsidiary Wheaton Bank & Trust Company ("Wheaton Bank"). The Company acquired assets with a fair value of approximately $350.5 million , including approximately $159.5 million of loans, and assumed deposits with a fair value of approximately $290.0 million . Additionally, the Company recorded goodwill of $27.5 million on the acquisition. On July 17, 2015 , the Company acquired Suburban Illinois Bancorp, Inc. ("Suburban"). Suburban was the parent company of Suburban Bank & Trust Company ("SBT"), which operated ten banking locations. SBT was merged into the Company's wholly-owned subsidiary Hinsdale Bank & Trust Company ("Hinsdale Bank"). The Company acquired assets with a fair value of approximately $494.7 million , including approximately $257.8 million of loans, and assumed deposits with a fair value of approximately $416.7 million . Additionally, the Company recorded goodwill of $18.8 million on the acquisition. On July 1, 2015 , the Company, through its wholly-owned subsidiary Wintrust Bank, acquired North Bank, which had two banking locations. The Company acquired assets with a fair value of $101.0 million , including approximately $51.6 million of loans, and assumed deposits with a fair value of approximately $100.3 million . Additionally, the Company recorded goodwill of $6.7 million on the acquisition. On January 16, 2015 , the Company acquired Delavan Bancshares, Inc. ("Delavan"). Delavan was the parent company of Community Bank CBD, which had four banking locations. Community Bank CBD was merged into the Company's wholly-owned subsidiary Town Bank. The Company acquired assets with a fair value of approximately $224.1 million , including approximately $128.0 million of loans, and assumed liabilities with a fair value of approximately $186.4 million , including approximately $170.2 million of deposits. Additionally the Company recorded goodwill of $16.3 million on the acquisition. On August 8, 2014 , the Company, through its wholly-owned subsidiary Town Bank, acquired eleven branch offices and deposits of Talmer Bank & Trust. Subsequent to this date, the Company acquired loans from these branches as well. In total, the Company acquired assets with a fair value of approximately $361.3 million , including approximately $41.5 million of loans, and assumed liabilities with a fair value of approximately $361.3 million , including approximately $354.9 million of deposits. Additionally, the Company recorded goodwill of $9.7 million on the acquisition. On July 11, 2014 the Company, through its wholly-owned subsidiary Town Bank, acquired the Pewaukee, Wisconsin branch of THE National Bank. The Company acquired assets with a fair value of approximately $94.1 million , including approximately $75.0 million of loans, and assumed deposits with a fair value of approximately $36.2 million . Additionally, the Company recorded goodwill of $16.3 million on the acquisition. On May 16, 2014 , the Company, through its wholly-owned subsidiary Hinsdale Bank acquired the Stone Park branch office and certain related deposits of Urban Partnership Bank ("UPB"). The Company assumed liabilities with a fair value of approximately $5.5 million , including approximately $5.4 million of deposits. Additionally, the Company recorded goodwill of $678,000 on the acquisition. FDIC-Assisted Transactions Since 2010, 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 comprise the majority of the assets acquired in nearly all of these FDIC-assisted transactions, most of which are subject to loss sharing agreements with the FDIC whereby the FDIC has 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 require the Company to reimburse the FDIC in the event that actual losses on covered assets are 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. The agreements with the FDIC require that the Company follow certain servicing procedures or risk losing the FDIC reimbursement of covered asset losses. The loans covered by the loss sharing agreements are classified and presented as covered loans and the estimated reimbursable losses are recorded as an FDIC indemnification asset 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 will only recognize a provision for credit losses and charge-offs on the acquired loans for any further credit deterioration subsequent to the acquisition date. See Note 7 — 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 cover realized losses on loans, foreclosed real estate and certain other assets and require the Company to record loss share assets and liabilities that are measured separately from the loan portfolios because they are not contractually embedded in the loans and are 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 are recorded as FDIC indemnification assets and other liabilities, respectively, on the Consolidated Statements of Condition. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses will reduce the FDIC indemnification assets. Reductions to expected losses, to the extent such reductions to expected losses are the result of an improvement to the actual or expected cash flows from the covered assets, will also reduce the FDIC indemnification assets and, if necessary, increase any loss share liability when necessary reductions exceed the current value of the FDIC indemnification assets. In accordance with the clawback provision noted above, the Company may be required to reimburse the FDIC when actual losses are less than certain thresholds established for each lose share agreement. The balance of these estimated reimbursements in accordance with clawback provisions and any related amortization are adjusted periodically for changes in the expected losses on covered assets. On the Consolidated Statements of Condition, estimated reimbursements from clawback provisions are recorded as a reduction to the FDIC indemnification asset or, if necessary, an increase to the loss share liability, which is included within accrued interest payable and other liabilities. Although these assets are contractual receivables from the FDIC, there are no contractual interest rates. Additional expected losses, to the extent such expected losses result in recognition of an allowance for covered loan losses, will increase the FDIC indemnification asset. The corresponding amortization is recorded as a component of non-interest income on the Consolidated Statements of Income. The following table summarizes the activity in the Company’s FDIC indemnification (liability) asset during the periods indicated: Three Months Ended Nine Months Ended (Dollars in thousands) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Balance at beginning of period $ 3,429 $ 46,115 $ 11,846 $ 85,672 Additions from acquisitions — — — — Additions from reimbursable expenses 1,039 1,584 3,548 4,933 Amortization (718 ) (1,382 ) (3,184 ) (4,441 ) Changes in expected reimbursements from the FDIC for changes in expected credit losses (5,236 ) (12,124 ) (13,546 ) (41,153 ) Payments received from the FDIC (1,547 ) (6,834 ) (1,697 ) (17,652 ) Balance at end of period $ (3,033 ) $ 27,359 $ (3,033 ) $ 27,359 Specialty Finance Acquisition On April 28, 2014 , the Company, through its wholly-owned subsidiary, First Insurance Funding of Canada, Inc., acquired Policy Billing Services Inc. and Equity Premium Finance Inc., two affiliated Canadian insurance premium funding and payment services companies. Through this transaction, the Company acquired approximately $7.4 million of premium finance receivables. The Company recorded goodwill of approximately $6.5 million on the acquisition. Purchased Credit Impaired ("PCI") Loans Purchased loans acquired in a business combination are recorded at estimated fair value on their purchase date. 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 generally 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 with the accretable component being recognized into interest income using the effective yield method over the estimated remaining life of the loans. The non-accretable portion is evaluated each quarter and if the loans’ credit related conditions improve, a portion is transferred to the accretable component and accreted over future periods. In the event a specific loan prepays in whole, any remaining accretable and non-accretable discount is recognized in income immediately. If credit related conditions deteriorate, an allowance related to these loans will be established as part of the provision for credit losses. See Note 6—Loans, for more information on PCI loans.

Cash and Cash Equivalents

Cash and Cash Equivalents	9 Months Ended
	Sep. 30, 2015
Cash and Cash Equivalents [Abstract]
Cash and Cash Equivalents	Cash and Cash Equivalents For purposes of the Consolidated Statements of Cash Flows, the Company considers cash and cash equivalents to include 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.

Available-For-Sale Securities

Available-For-Sale Securities	9 Months Ended
	Sep. 30, 2015
Available-for-sale Securities [Abstract]
Investments in Debt and Marketable Equity Securities	Available-For-Sale Securities The following tables are a summary of the available-for-sale securities portfolio as of the dates shown: September 30, 2015 (Dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury $ 288,185 $ 101 $ (2,364 ) $ 285,922 U.S. Government agencies 657,297 2,726 (15,000 ) 645,023 Municipal 294,073 5,354 (2,085 ) 297,342 Corporate notes: Financial issuers 114,976 1,656 (1,216 ) 115,416 Other 1,525 6 (2 ) 1,529 Mortgage-backed: (1) Mortgage-backed securities 778,240 4,974 (10,913 ) 772,301 Collateralized mortgage obligations 42,724 343 (323 ) 42,744 Equity securities 49,356 4,993 (345 ) 54,004 Total available-for-sale securities $ 2,226,376 $ 20,153 $ (32,248 ) $ 2,214,281 December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (Dollars in thousands) U.S. Treasury $ 388,713 $ 84 $ (6,992 ) $ 381,805 U.S. Government agencies 686,106 4,113 (21,903 ) 668,316 Municipal 234,951 5,318 (1,740 ) 238,529 Corporate notes: Financial issuers 129,309 2,006 (1,557 ) 129,758 Other 3,766 55 — 3,821 Mortgage-backed: (1) Mortgage-backed securities 271,129 5,448 (4,928 ) 271,649 Collateralized mortgage obligations 47,347 249 (535 ) 47,061 Equity securities 46,592 4,872 (325 ) 51,139 Total available-for-sale securities $ 1,807,913 $ 22,145 $ (37,980 ) $ 1,792,078 September 30, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (Dollars in thousands) U.S. Treasury $ 388,873 $ 372 $ (10,984 ) $ 378,261 U.S. Government agencies 771,255 3,866 (35,369 ) 739,752 Municipal 184,015 4,969 (1,881 ) 187,103 Corporate notes: Financial issuers 129,259 2,252 (1,208 ) 130,303 Other 3,773 79 — 3,852 Mortgage-backed: (1) Mortgage-backed securities 246,354 4,303 (8,938 ) 241,719 Collateralized mortgage obligations 49,909 357 (763 ) 49,503 Equity securities 47,595 4,958 (398 ) 52,155 Total available-for-sale securities $ 1,821,033 $ 21,156 $ (59,541 ) $ 1,782,648 (1) Consisting entirely of residential mortgage-backed securities, none of which are subprime. The following table presents the portion of the Company’s available-for-sale securities portfolio which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at September 30, 2015 : 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 U.S. Treasury $ 202,795 $ (2,364 ) $ — $ — $ 202,795 $ (2,364 ) U.S. Government agencies 218,297 (4,932 ) 251,654 (10,068 ) 469,951 (15,000 ) Municipal 68,140 (964 ) 37,002 (1,121 ) 105,142 (2,085 ) Corporate notes: Financial issuers 23,052 (152 ) 44,894 (1,064 ) 67,946 (1,216 ) Other 999 (2 ) — — 999 (2 ) Mortgage-backed: Mortgage-backed securities 519,631 (7,011 ) 120,261 (3,902 ) 639,892 (10,913 ) Collateralized mortgage obligations 7,167 (63 ) 9,620 (260 ) 16,787 (323 ) Equity securities 2,957 (12 ) 8,557 (333 ) 11,514 (345 ) Total $ 1,043,038 $ (15,500 ) $ 471,988 $ (16,748 ) $ 1,515,026 $ (32,248 ) 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 September 30, 2015 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 agency bonds and mortgage-backed securities. Unrealized losses recognized on agency bonds and mortgage-backed securities are the result of increases in yields for similar types of securities which also have a longer duration and maturity. The following table provides information as to the amount of gross gains and gross losses realized and proceeds received through the sales of available-for-sale investment securities: Three months ended September 30, Nine months ended September 30, (Dollars in thousands) 2015 2014 2015 2014 Realized gains $ 87 $ 179 $ 654 $ 333 Realized losses (185 ) (332 ) (252 ) (855 ) Net realized (losses) gains $ (98 ) $ (153 ) $ 402 $ (522 ) Other than temporary impairment charges — — — — (Losses) gains on available-for-sale securities, net $ (98 ) $ (153 ) $ 402 $ (522 ) Proceeds from sales of available-for-sale securities $ 82,827 $ 382,552 $ 1,216,860 $ 578,594 The amortized cost and fair value of securities as of September 30, 2015 , December 31, 2014 and September 30, 2014 , 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: September 30, 2015 December 31, 2014 September 30, 2014 (Dollars in thousands) Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Due in one year or less $ 164,374 $ 164,429 $ 285,596 $ 285,889 $ 216,244 $ 216,582 Due in one to five years 186,199 186,592 172,647 172,885 309,914 310,917 Due in five to ten years 343,468 342,271 331,389 325,644 327,505 317,654 Due after ten years 662,015 651,940 653,213 637,811 623,512 594,118 Mortgage-backed 820,964 815,045 318,476 318,710 296,263 291,222 Equity securities 49,356 54,004 46,592 51,139 47,595 52,155 Total available-for-sale securities $ 2,226,376 $ 2,214,281 $ 1,807,913 $ 1,792,078 $ 1,821,033 $ 1,782,648 Securities having a carrying value of $1.3 billion at September 30, 2015 as well as securities having a carrying value of $1.1 billion at December 31, 2014 and September 30, 2014 , were pledged as collateral for public deposits, trust deposits, FHLB advances, securities sold under repurchase agreements and derivatives. At September 30, 2015 , there were no securities of a single issuer, other than U.S. Government-sponsored agency securities, which exceeded 10% of shareholders’ equity.

Loans

Loans	9 Months Ended
	Sep. 30, 2015
Loans and Leases Receivable Disclosure [Abstract]
Loans	Loans The following table shows the Company’s loan portfolio by category as of the dates shown: September 30, December 31, September 30, (Dollars in thousands) 2015 2014 2014 Balance: Commercial $ 4,400,185 $ 3,924,394 $ 3,689,671 Commercial real estate 5,307,566 4,505,753 4,510,375 Home equity 797,465 716,293 720,058 Residential real estate 571,743 483,542 470,319 Premium finance receivables—commercial 2,407,075 2,350,833 2,377,892 Premium finance receivables—life insurance 2,700,275 2,277,571 2,134,405 Consumer and other 131,902 151,012 149,339 Total loans, net of unearned income, excluding covered loans $ 16,316,211 $ 14,409,398 $ 14,052,059 Covered loans 168,609 226,709 254,605 Total loans $ 16,484,820 $ 14,636,107 $ 14,306,664 Mix: Commercial 27 % 26 % 26 % Commercial real estate 32 31 31 Home equity 5 5 5 Residential real estate 3 3 3 Premium finance receivables—commercial 15 16 17 Premium finance receivables—life insurance 16 16 15 Consumer and other 1 1 1 Total loans, net of unearned income, excluding covered loans 99 % 98 % 98 % Covered loans 1 2 2 Total loans 100 % 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 $53.4 million at September 30, 2015 , $46.9 million at December 31, 2014 and $44.8 million at September 30, 2014 , respectively. Certain life insurance premium finance receivables attributable to the life insurance premium finance loan acquisition in 2009 as well as PCI loans are recorded net of credit discounts. See “Acquired Loan Information at Acquisition” below. Total loans, excluding PCI loans, include net deferred loan fees and costs and fair value purchase accounting adjustments totaling $(18.8) million at September 30, 2015 , $330,000 at December 31, 2014 and $(6.3) million at September 30, 2014 . The net credit balance at September 30, 2015 and September 30, 2014, is primarily the result of purchase accounting adjustments related to acquisitions in 2015 and 2014, respectively. 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 ensure 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 our previous acquisitions, we 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: September 30, 2015 December 31, 2014 Unpaid Principal Carrying Unpaid Principal Carrying (Dollars in thousands) Balance Value Balance Value Bank acquisitions $ 356,615 $ 295,801 $ 285,809 $ 227,229 Life insurance premium finance loans acquisition 378,040 373,586 399,665 393,479 The following table provides estimated details as of the date of acquisition on loans acquired in 2015 with evidence of credit quality deterioration since origination: (Dollars in thousands) North Bank CBWGE Suburban Delavan Contractually required payments including interest $ 8,563 $ 38,656 $ 95,804 $ 15,791 Less: Nonaccretable difference 1,027 4,437 13,888 1,442 Cash flows expected to be collected (1) 7,536 34,219 81,916 14,349 Less: Accretable yield 866 2,895 5,334 898 Fair value of PCI loans acquired 6,670 31,324 76,582 13,451 (1) Represents undiscounted expected principal and interest cash at acquisition. See Note 7—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 September 30, 2015 . 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: Three Months Ended Nine Months Ended (Dollars in thousands) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Accretable yield, beginning balance $ 63,643 $ 97,281 $ 79,102 $ 115,909 Acquisitions 9,095 — 9,993 — Accretable yield amortized to interest income (5,939 ) (7,847 ) (18,359 ) (28,438 ) Accretable yield amortized to indemnification asset (1) (3,280 ) (8,784 ) (10,945 ) (25,593 ) Reclassification from non-accretable difference (2) 2,298 2,584 5,154 29,092 Increases (decreases) in interest cash flows due to payments and changes in interest rates (610 ) 4,675 262 (3,061 ) Accretable yield, ending balance (3) $ 65,207 $ 87,909 $ 65,207 $ 87,909 (1) Represents the portion of the current period accreted yield, resulting from lower expected losses, applied to reduce the loss share indemnification asset. (2) Reclassification is the result of subsequent increases in expected principal cash flows. (3) As of September 30, 2015, the Company estimates that the remaining accretable yield balance to be amortized to the indemnification asset for the bank acquisitions is $10.0 million . The remainder of the accretable yield related to bank acquisitions is expected to be amortized to interest income. Accretion to interest income from acquired loans totaled $5.9 million and $7.8 million in the third quarter of 2015 and 2014, respectively. For the nine months ended September 30, 2015 and 2014, the Company recorded accretion to interest income of $18.4 million and $28.4 million , 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	9 Months Ended
	Sep. 30, 2015
Loans and Leases Receivable, Allowance [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 September 30, 2015 , December 31, 2014 and September 30, 2014 : As of September 30, 2015 90+ days and still accruing 60-89 days past due 30-59 days past due (Dollars in thousands) Nonaccrual Current Total Loans Loan Balances: Commercial Commercial and industrial $ 12,006 $ — $ 2,731 $ 9,331 $ 2,622,207 $ 2,646,275 Franchise — — 80 376 221,545 222,001 Mortgage warehouse lines of credit — — — — 136,614 136,614 Community Advantage—homeowners association — — 44 — 123,165 123,209 Aircraft — — — 378 5,993 6,371 Asset-based lending 12 — 1,313 247 800,798 802,370 Tax exempt — — — — 232,667 232,667 Leases — — — 89 205,697 205,786 Other — — — — 1,953 1,953 PCI - commercial (1) — 217 — 39 22,683 22,939 Total commercial 12,018 217 4,168 10,460 4,373,322 4,400,185 Commercial real estate: Residential construction — — — 1,141 60,130 61,271 Commercial construction 31 — — 2,394 283,538 285,963 Land 1,756 — — 2,207 75,113 79,076 Office 4,045 — 10,861 2,362 773,043 790,311 Industrial 11,637 — 786 897 622,804 636,124 Retail 2,022 — 1,536 821 781,463 785,842 Multi-family 1,525 — 512 744 684,878 687,659 Mixed use and other 7,601 — 2,340 12,871 1,797,516 1,820,328 PCI - commercial real estate (1) — 13,547 299 583 146,563 160,992 Total commercial real estate 28,617 13,547 16,334 24,020 5,225,048 5,307,566 Home equity 8,365 — 811 4,124 784,165 797,465 Residential real estate 14,557 — 1,017 1,195 551,292 568,061 PCI - residential real estate (1) — 424 323 411 2,524 3,682 Premium finance receivables Commercial insurance loans 13,751 8,231 6,664 13,659 2,364,770 2,407,075 Life insurance loans — — 9,656 2,627 2,314,406 2,326,689 PCI - life insurance loans (1) — — — — 373,586 373,586 Consumer and other 297 140 56 935 130,474 131,902 Total loans, net of unearned income, excluding covered loans $ 77,605 $ 22,559 $ 39,029 $ 57,431 $ 16,119,587 $ 16,316,211 Covered loans 6,540 7,626 1,392 802 152,249 168,609 Total loans, net of unearned income $ 84,145 $ 30,185 $ 40,421 $ 58,233 $ 16,271,836 $ 16,484,820 (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. As of December 31, 2014 90+ days and still accruing 60-89 days past due 30-59 days past due (Dollars in thousands) Nonaccrual Current Total Loans Loan Balances: Commercial Commercial and industrial $ 9,132 $ 474 $ 3,161 $ 7,492 $ 2,213,105 $ 2,233,364 Franchise — — 308 1,219 231,789 233,316 Mortgage warehouse lines of credit — — — — 139,003 139,003 Community Advantage—homeowners association — — — — 106,364 106,364 Aircraft — — — — 8,065 8,065 Asset-based lending 25 — 1,375 2,394 802,608 806,402 Tax exempt — — — — 217,487 217,487 Leases — — 77 315 159,744 160,136 Other — — — — 11,034 11,034 PCI - commercial (1) — 365 202 138 8,518 9,223 Total commercial 9,157 839 5,123 11,558 3,897,717 3,924,394 Commercial real estate Residential construction — — 250 76 38,370 38,696 Commercial construction 230 — — 2,023 185,513 187,766 Land 2,656 — — 2,395 86,779 91,830 Office 7,288 — 2,621 1,374 694,149 705,432 Industrial 2,392 — — 3,758 617,820 623,970 Retail 4,152 — 116 3,301 723,919 731,488 Multi-family 249 — 249 1,921 603,323 605,742 Mixed use and other 9,638 — 2,603 9,023 1,443,853 1,465,117 PCI - commercial real estate (1) — 10,976 6,393 4,016 34,327 55,712 Total commercial real estate 26,605 10,976 12,232 27,887 4,428,053 4,505,753 Home equity 6,174 — 983 3,513 705,623 716,293 Residential real estate 15,502 — 267 6,315 459,224 481,308 PCI - residential real estate (1) — 549 — — 1,685 2,234 Premium finance receivables Commercial insurance loans 12,705 7,665 5,995 17,328 2,307,140 2,350,833 Life insurance loans — — 13,084 339 1,870,669 1,884,092 PCI - life insurance loans (1) — — — — 393,479 393,479 Consumer and other 277 119 293 838 149,485 151,012 Total loans, net of unearned income, excluding covered loans $ 70,420 $ 20,148 $ 37,977 $ 67,778 $ 14,213,075 $ 14,409,398 Covered loans 7,290 17,839 1,304 4,835 195,441 226,709 Total loans, net of unearned income $ 77,710 $ 37,987 $ 39,281 $ 72,613 $ 14,408,516 $ 14,636,107 (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. As of September 30, 2014 90+ days and still accruing 60-89 days past due 30-59 days past due (Dollars in thousands) Nonaccrual Current Total Loans Loan Balances: Commercial Commercial and industrial $ 10,430 $ — $ 7,333 $ 8,559 $ 2,044,505 $ 2,070,827 Franchise — — — 1,221 237,079 238,300 Mortgage warehouse lines of credit — — — — 121,585 121,585 Community Advantage—homeowners association — — — — 99,595 99,595 Aircraft — — — — 6,146 6,146 Asset-based lending 25 — 2,959 1,220 777,723 781,927 Tax exempt — — — — 205,150 205,150 Leases — — — — 145,439 145,439 Other — — — — 11,403 11,403 PCI - commercial (1) — 863 64 137 8,235 9,299 Total commercial 10,455 863 10,356 11,137 3,656,860 3,689,671 Commercial real estate: Residential construction — — — — 30,237 30,237 Commercial construction 425 — — — 159,383 159,808 Land 2,556 — 1,316 2,918 94,449 101,239 Office 7,366 — 1,696 1,888 688,390 699,340 Industrial 2,626 — 224 367 624,669 627,886 Retail 6,205 — — 4,117 715,568 725,890 Multi-family 249 — 793 2,319 674,610 677,971 Mixed use and other 7,936 — 1,468 10,323 1,407,659 1,427,386 PCI - commercial real estate (1) — 14,294 — 5,807 40,517 60,618 Total commercial real estate 27,363 14,294 5,497 27,739 4,435,482 4,510,375 Home equity 5,696 — 1,181 2,597 710,584 720,058 Residential real estate 15,730 — 670 2,696 448,528 467,624 PCI - residential real estate (1) — 930 30 — 1,735 2,695 Premium finance receivables Commercial insurance loans 14,110 7,115 6,279 14,157 2,336,231 2,377,892 Life insurance loans — — 7,533 6,942 1,712,328 1,726,803 PCI - life insurance loans (1) — — — — 407,602 407,602 Consumer and other 426 175 123 1,133 147,482 149,339 Total loans, net of unearned income, excluding covered loans $ 73,780 $ 23,377 $ 31,669 $ 66,401 $ 13,856,832 $ 14,052,059 Covered loans 6,042 26,170 4,289 5,655 212,449 254,605 Total loans, net of unearned income $ 79,822 $ 49,547 $ 35,958 $ 72,056 $ 14,069,281 $ 14,306,664 (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. Our 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 our 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 automatically 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 we determine 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 and covered 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, excluding covered loans, per the most recent analysis at September 30, 2015 , December 31, 2014 and September 30, 2014 : Performing Non-performing Total (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 September 30, December 31, 2014 September 30, September 30, December 31, 2014 September 30, Loan Balances: Commercial Commercial and industrial $ 2,634,269 $ 2,223,758 $ 2,060,397 $ 12,006 $ 9,606 $ 10,430 $ 2,646,275 $ 2,233,364 $ 2,070,827 Franchise 222,001 233,316 238,300 — — — 222,001 233,316 238,300 Mortgage warehouse lines of credit 136,614 139,003 121,585 — — — 136,614 139,003 121,585 Community Advantage—homeowners association 123,209 106,364 99,595 — — — 123,209 106,364 99,595 Aircraft 6,371 8,065 6,146 — — — 6,371 8,065 6,146 Asset-based lending 802,358 806,377 781,902 12 25 25 802,370 806,402 781,927 Tax exempt 232,667 217,487 205,150 — — — 232,667 217,487 205,150 Leases 205,786 160,136 145,439 — — — 205,786 160,136 145,439 Other 1,953 11,034 11,403 — — — 1,953 11,034 11,403 PCI - commercial (1) 22,939 9,223 9,299 — — — 22,939 9,223 9,299 Total commercial 4,388,167 3,914,763 3,679,216 12,018 9,631 10,455 4,400,185 3,924,394 3,689,671 Commercial real estate Residential construction 61,271 38,696 30,237 — — — 61,271 38,696 30,237 Commercial construction 285,932 187,536 159,383 31 230 425 285,963 187,766 159,808 Land 77,320 89,174 98,683 1,756 2,656 2,556 79,076 91,830 101,239 Office 786,266 698,144 691,974 4,045 7,288 7,366 790,311 705,432 699,340 Industrial 624,487 621,578 625,260 11,637 2,392 2,626 636,124 623,970 627,886 Retail 783,820 727,336 719,685 2,022 4,152 6,205 785,842 731,488 725,890 Multi-family 686,134 605,493 677,722 1,525 249 249 687,659 605,742 677,971 Mixed use and other 1,812,727 1,455,479 1,419,450 7,601 9,638 7,936 1,820,328 1,465,117 1,427,386 PCI - commercial real estate (1) 160,992 55,712 60,618 — — — 160,992 55,712 60,618 Total commercial real estate 5,278,949 4,479,148 4,483,012 28,617 26,605 27,363 5,307,566 4,505,753 4,510,375 Home equity 789,100 710,119 714,362 8,365 6,174 5,696 797,465 716,293 720,058 Residential real estate 553,504 465,806 451,894 14,557 15,502 15,730 568,061 481,308 467,624 PCI - residential real estate (1) 3,682 2,234 2,695 — — — 3,682 2,234 2,695 Premium finance receivables Commercial insurance loans 2,385,093 2,330,463 2,356,667 21,982 20,370 21,225 2,407,075 2,350,833 2,377,892 Life insurance loans 2,326,689 1,884,092 1,726,803 — — — 2,326,689 1,884,092 1,726,803 PCI - life insurance loans (1) 373,586 393,479 407,602 — — — 373,586 393,479 407,602 Consumer and other 131,465 150,617 148,738 437 395 601 131,902 151,012 149,339 Total loans, net of unearned income, excluding covered loans $ 16,230,235 $ 14,330,721 $ 13,970,989 $ 85,976 $ 78,677 $ 81,070 $ 16,316,211 $ 14,409,398 $ 14,052,059 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 6 - Loans for further discussion of these purchased loans. A summary of activity in the allowance for credit losses by loan portfolio (excluding covered loans) for the three months ended September 30, 2015 and 2014 is as follows: Three months ended September 30, 2015 Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Commercial Allowance for credit losses Allowance for loan losses at beginning of period $ 32,900 $ 42,198 $ 12,288 $ 5,019 $ 6,921 $ 878 $ 100,204 Other adjustments (12 ) (85 ) — (6 ) (50 ) — (153 ) Reclassification from allowance for unfunded lending-related commitments — (42 ) — — — — (42 ) Charge-offs (964 ) (1,948 ) (1,116 ) (1,138 ) (1,595 ) (116 ) (6,877 ) Recoveries 462 213 42 136 294 52 1,199 Provision for credit losses 1,604 3,725 1,009 575 1,511 241 8,665 Allowance for loan losses at period end $ 33,990 $ 44,061 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 102,996 Allowance for unfunded lending-related commitments at period end $ — $ 926 $ — $ — $ — $ — $ 926 Allowance for credit losses at period end $ 33,990 $ 44,987 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 103,922 Individually evaluated for impairment $ 1,881 $ 5,832 $ 239 $ 544 $ — $ 30 $ 8,526 Collectively evaluated for impairment 31,943 38,361 11,984 4,042 7,081 1,024 94,435 Loans acquired with deteriorated credit quality 166 794 — — — 1 961 Loans at period end Individually evaluated for impairment $ 18,211 $ 68,947 $ 8,365 $ 18,267 $ — $ 430 $ 114,220 Collectively evaluated for impairment 4,359,035 5,077,627 789,100 549,794 4,733,764 131,472 15,640,792 Loans acquired with deteriorated credit quality 22,939 160,992 — 3,682 373,586 — 561,199 Three months ended September 30, 2014 Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Allowance for credit losses Allowance for loan losses at beginning of period $ 26,038 $ 40,702 $ 13,918 $ 3,733 $ 6,309 $ 1,553 $ 92,253 Other adjustments (32 ) (265 ) (1 ) (2 ) (35 ) — (335 ) Reclassification from allowance for unfunded lending-related commitments — 62 — — — — 62 Charge-offs (832 ) (4,510 ) (748 ) (205 ) (1,557 ) (250 ) (8,102 ) Recoveries 296 275 99 111 290 42 1,113 Provision for credit losses 2,442 2,395 (308 ) 405 1,260 (166 ) 6,028 Allowance for loan losses at period end $ 27,912 $ 38,659 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,019 Allowance for unfunded lending-related commitments at period end $ — $ 822 $ — $ — $ — $ — $ 822 Allowance for credit losses at period end $ 27,912 $ 39,481 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,841 Individually evaluated for impairment $ 2,296 $ 3,507 $ 292 $ 512 $ — $ 53 $ 6,660 Collectively evaluated for impairment 25,427 35,967 12,668 3,530 6,267 1,103 84,962 Loans acquired with deteriorated credit quality 189 7 — — — 23 219 Loans at period end Individually evaluated for impairment $ 16,568 $ 89,201 $ 5,922 $ 18,383 $ — $ 870 $ 130,944 Collectively evaluated for impairment 3,663,804 4,360,556 714,136 449,241 4,104,695 148,469 13,440,901 Loans acquired with deteriorated credit quality 9,299 60,618 — 2,695 407,602 — 480,214 Nine months ended September 30, 2015 Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Commercial Allowance for credit losses Allowance for loan losses at beginning of period $ 31,699 $ 35,533 $ 12,500 $ 4,218 $ 6,513 $ 1,242 $ 91,705 Other adjustments (42 ) (346 ) — (14 ) (92 ) — (494 ) Reclassification from allowance for unfunded lending-related commitments — (151 ) — — — — (151 ) Charge-offs (2,884 ) (3,809 ) (3,547 ) (2,692 ) (4,384 ) (342 ) (17,658 ) Recoveries 1,117 2,349 129 228 1,081 139 5,043 Provision for credit losses 4,100 10,485 3,141 2,846 3,963 16 24,551 Allowance for loan losses at period end $ 33,990 $ 44,061 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 102,996 Allowance for unfunded lending-related commitments at period end $ — $ 926 $ — $ — $ — $ — $ 926 Allowance for credit losses at period end $ 33,990 $ 44,987 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 103,922 Nine months ended September 30, 2014 Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Allowance for credit losses Allowance for loan losses at beginning of period $ 23,092 $ 48,658 $ 12,611 $ 5,108 $ 5,583 $ 1,870 $ 96,922 Other adjustments (69 ) (482 ) (3 ) (6 ) (28 ) — (588 ) Reclassification from allowance for unfunded lending-related commitments — (102 ) — — — — (102 ) Charge-offs (3,864 ) (11,354 ) (3,745 ) (1,120 ) (4,259 ) (636 ) (24,978 ) Recoveries 883 762 478 316 925 256 3,620 Provision for credit losses 7,870 1,177 3,619 (256 ) 4,046 (311 ) 16,145 Allowance for loan losses at period end $ 27,912 $ 38,659 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,019 Allowance for unfunded lending-related commitments at period end $ — $ 822 $ — $ — $ — $ — $ 822 Allowance for credit losses at period end $ 27,912 $ 39,481 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,841 A summary of activity in the allowance for covered loan losses for the three months ended September 30, 2015 and 2014 is as follows: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, (Dollars in thousands) 2015 2014 2015 2014 Balance at beginning of period $ 2,215 $ 1,667 $ 2,131 $ 10,092 Provision for covered loan losses before benefit attributable to FDIC loss share agreements (1,716 ) (818 ) (3,339 ) (8,703 ) Benefit attributable to FDIC loss share agreements 1,373 654 2,671 6,962 Net provision for covered loan losses (343 ) (164 ) (668 ) (1,741 ) Decrease in FDIC indemnification asset (1,373 ) (654 ) (2,671 ) (6,962 ) Loans charged-off (287 ) (293 ) (664 ) (5,346 ) Recoveries of loans charged-off 2,706 2,099 4,790 6,612 Net recoveries (charge-offs) 2,419 1,806 4,126 1,266 Balance at end of period $ 2,918 $ 2,655 $ 2,918 $ 2,655 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 result in the recognition of an allowance for loan losses, will increase the FDIC indemnification asset. The allowance for loan losses for loans acquired in FDIC-assisted transactions is 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 is 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 are the result of an improvement to the actual or expected cash flows from the covered assets, will reduce the FDIC indemnification asset. Additions to expected losses will require an increase to the allowance for loan losses, and a corresponding increase to the FDIC indemnification asset. See “FDIC-Assisted Transactions” within Note 3 – Business Combinations for more detail. Impaired Loans A summary of impaired loans, including troubled debt restructurings ("TDRs"), is as follows: September 30, December 31, September 30, (Dollars in thousands) 2015 2014 2014 Impaired loans (included in non-performing and TDRs): Impaired loans with an allowance for loan loss required (1) $ 51,113 $ 69,487 $ 68,471 Impaired loans with no allowance for loan loss required 61,914 57,925 61,066 Total impaired loans (2) $ 113,027 $ 127,412 $ 129,537 Allowance for loan losses related to impaired loans $ 8,483 $ 6,270 $ 6,577 TDRs $ 59,320 $ 82,275 $ 83,385 (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 for the periods ended as follows: For the Nine Months Ended As of September 30, 2015 September 30, 2015 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (Dollars in thousands) Impaired loans with a related ASC 310 allowance recorded Commercial Commercial and industrial $ 8,580 $ 9,118 $ 1,865 $ 8,906 $ 381 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending — — — — — Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction — — — — — Land 3,559 7,309 31 3,713 362 Office 6,765 7,724 2,162 7,113 263 Industrial 10,049 10,542 1,550 10,662 421 Retail 8,899 9,596 381 8,906 306 Multi-family 1,199 1,622 203 1,210 60 Mixed use and other 7,162 7,345 1,501 7,250 224 Home equity 547 762 239 672 25 Residential real estate 4,225 4,326 521 4,280 130 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — PCI - life insurance — — — — — Consumer and other 128 128 30 139 6 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial and industrial $ 9,142 $ 11,997 $ — $ 9,716 $ 539 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending 12 1,573 — 4 66 Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction 2,023 2,023 — 2,023 73 Commercial construction 31 32 — 11 — Land 4,114 4,874 — 4,232 130 Office 4,171 5,120 — 4,243 194 Industrial 2,255 2,448 — 2,304 141 Retail 3,140 3,302 — 3,305 104 Multi-family 1,330 1,635 — 1,522 50 Mixed use and other 13,788 16,576 — 14,668 563 Home equity 7,818 8,406 — 7,065 229 Residential real estate 13,788 15,932 — 14,387 449 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — PCI - life insurance — — — — — Consumer and other 302 398 — 311 15 Total loans, net of unearned income, excluding covered loans $ 113,027 $ 132,788 $ 8,483 $ 116,642 $ 4,731 For the Twelve Months Ended As of December 31, 2014 December 31, 2014 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (Dollars in thousands) Impaired loans with a related ASC 310 allowance recorded Commercial Commercial and industrial $ 9,989 $ 10,785 $ 1,915 $ 10,784 $ 539 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending — — — — — Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction — — — — — Land 5,011 8,626 43 5,933 544 Office 11,038 12,863 305 11,567 576 Industrial 195 277 15 214 13 Retail 11,045 14,566 487 12,116 606 Multi-family 2,808 3,321 158 2,839 145 Mixed use and other 21,777 24,076 2,240 21,483 1,017 Home equity 1,946 2,055 475 1,995 80 Residential real estate 5,467 5,600 606 5,399 241 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 211 213 26 214 10 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial and industrial $ 5,797 $ 8,862 $ — $ 6,664 $ 595 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending 25 1,952 — 87 100 Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction 2,875 3,085 — 3,183 151 Land 10,210 10,941 — 10,268 430 Office 4,132 5,020 — 4,445 216 Industrial 4,160 4,498 — 3,807 286 Retail 5,487 7,470 — 6,915 330 Multi-family — — — — — Mixed use and other 7,985 8,804 — 9,533 449 Home equity 4,453 6,172 — 4,666 256 Residential real estate 12,640 14,334 — 12,682 595 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 161 222 — 173 11 Total loans, net of unearned income, excluding covered loans $ 127,412 $ 153,742 $ 6,270 $ 134,967 $ 7,190 For the Nine Months Ended As of September 30, 2014 September 30, 2014 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (Dollars in thousands) Impaired loans with a related ASC 310 allowance recorded Commercial Commercial and industrial $ 8,384 $ 11,333 $ 2,273 $ 9,367 $ 537 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending — — — — — Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction 425 440 195 432 15 Land 7,502 7,502 40 7,572 193 Office 8,198 9,671 322 8,493 300 Industrial 2,567 2,672 151 2,595 92 Retail 10,861 11,279 921 10,826 362 Multi-family 2,822 3,335 107 2,847 109 Mixed use and other 21,172 21,453 1,738 20,891 656 Home equity 1,438 1,533 292 1,491 42 Residential real estate 4,889 4,986 485 4,783 157 Premium finance receivables — Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 213 215 53 215 6 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial and industrial $ 7,563 $ 8,285 $ — $ 7,909 $ 306 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending 25 1,952 — 108 75 Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction 2,803 2,803 — 2,777 98 Land 8,101 12,432 — 8,969 538 Office 5,159 6,359 — 6,679 244 Industrial 1,903 2,110 — 1,962 76 Retail 8,095 10,177 — 8,647 342 Multi-family — — — — — Mixed use and other 9,042 11,772 — 9,467 445 Home equity 4,484 6,490 — 4,806 207 Residential real estate 13,234 14,953 — 13,291 496 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 657 721 — 665 29 Total loans, net of unearned income, excluding covered loans $ 129,537 $ 152,473 $ 6,577 $ 134,792 $ 5,325 TDRs At September 30, 2015 , the Company had $59.3 million in loans modified in TDRs. The $59.3 million in TDRs represents 114 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 six or worse or a modification of any other credit which will result in a restructured credit risk rating of six 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 five 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 five 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 at any subsequent re-modification 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 the 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

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2015
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, 2015 Goodwill Acquired Impairment Loss Goodwill Adjustments September 30, 2015 Community banking $ 331,752 $ 69,398 $ — $ — $ 401,150 Specialty finance 41,768 — — (2,866 ) 38,902 Wealth management 32,114 — — — 32,114 Total $ 405,634 $ 69,398 $ — $ (2,866 ) $ 472,166 The community banking segment's goodwill increased $69.4 million in the first nine months of 2015 as a result of the acquisitions of Delavan, Suburban, North Bank and CFIS. The specialty finance segment's goodwill decreased $2.9 million in the first nine months of 2015 as a result of foreign currency translation adjustments related to the Canadian acquisitions. At June 30, 2015, the Company utilized a qualitative approach for its annual goodwill impairment test of the community banking segment and determined that it is not more likely than not that an impairment existed at that time. The annual goodwill impairment tests of the specialty finance and wealth management segments will be conducted at December 31, 2015. A summary of finite-lived intangible assets as of the dates shown and the expected amortization as of September 30, 2015 is as follows: (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 Community banking segment: Core deposit intangibles: Gross carrying amount $ 34,840 $ 29,379 $ 40,438 Accumulated amortization (16,195 ) (17,879 ) (27,909 ) Net carrying amount $ 18,645 $ 11,500 $ 12,529 Specialty finance segment: Customer list intangibles: Gross carrying amount $ 1,800 $ 1,800 $ 1,800 Accumulated amortization (1,027 ) (941 ) (910 ) Net carrying amount $ 773 $ 859 $ 890 Wealth management segment: Customer list and other intangibles: Gross carrying amount $ 7,940 $ 7,940 $ 7,940 Accumulated amortization (1,825 ) (1,488 ) (1,375 ) Net carrying amount $ 6,115 $ 6,452 $ 6,565 Total other intangible assets, net $ 25,533 $ 18,811 $ 19,984 Estimated amortization Actual in nine months ended September 30, 2015 $ 3,297 Estimated remaining in 2015 1,325 Estimated—2016 4,663 Estimated—2017 3,876 Estimated—2018 3,371 Estimated—2019 2,854 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 ten -year period on a straight-line basis. Total amortization expense associated with finite-lived intangibles totaled approximately $3.3 million and $3.5 million for the nine months ended September 30, 2015 and 2014, respectively.

Deposits

Deposits	9 Months Ended
	Sep. 30, 2015
Deposits [Abstract]
Deposits	Deposits The following table is a summary of deposits as of the dates shown: (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 Balance: Non-interest bearing $ 4,705,994 $ 3,518,685 $ 3,253,477 NOW and interest bearing demand deposits 2,231,258 2,236,089 2,086,099 Wealth management deposits 1,469,920 1,226,916 1,212,317 Money market 4,001,518 3,651,467 3,744,682 Savings 1,684,007 1,508,877 1,465,250 Time certificates of deposit 4,135,772 4,139,810 4,303,421 Total deposits $ 18,228,469 $ 16,281,844 $ 16,065,246 Mix: Non-interest bearing 26 % 22 % 20 % NOW and interest bearing demand deposits 12 14 13 Wealth management deposits 8 8 8 Money market 22 22 23 Savings 9 9 9 Time certificates of deposit 23 25 27 Total deposits 100 % 100 % 100 % Wealth management deposits represent deposit balances (primarily money market accounts) at the Company’s subsidiary banks from brokerage customers of Wayne Hummer Investments, trust and asset management customers of CTC and brokerage customers from unaffiliated companies.

Federal Home Loan Bank Advances

Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes	Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes The following table is a summary of notes payable, Federal Home Loan Bank advances, other borrowings and subordinated notes as of the dates shown: (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 Federal Home Loan Bank advances $ 451,330 $ 733,050 $ 347,500 Other borrowings: Notes payable 71,250 — — Securities sold under repurchase agreements 57,590 48,566 32,530 Other 18,466 18,822 18,953 Secured borrowings 112,672 129,077 — Total other borrowings 259,978 196,465 51,483 Subordinated notes 140,000 140,000 140,000 Total Federal Home Loan Bank advances, other borrowings and subordinated notes $ 851,308 $ 1,069,515 $ 538,983 Federal Home Loan Bank Advances Federal Home Loan Bank advances consist of obligations of the banks and are collateralized by qualifying residential real estate and home equity loans and certain securities. FHLB advances are stated at par value of the debt adjusted for unamortized fair value adjustments recorded in connection with advances acquired through acquisitions. Notes Payable At September 30, 2015, notes payable represented a $71.3 million term facility ("Term Facility"), which is part of a $150.0 million loan agreement with unaffiliated banks dated December 15, 2014 . The agreement consists of the Term Facility and a $75.0 million revolving credit facility ("Revolving Credit Facility"). At September 30, 2015, the Company had an outstanding balance of $71.3 million compared to no outstanding balance at December 31, 2014 under the Term Facility. The Company was required to borrow the entire amount of the Term Facility on June 15, 2015 and all such borrowings must be repaid by June 15, 2020 . Beginning September 30, 2015 , the Company is required to make straight-line quarterly amortizing payments on the Term Facility. At September 30, 2015 and December 31, 2014, the Company had no outstanding balance under the Revolving Credit Facility. All borrowings under the Revolving Credit Facility must be repaid by December 14, 2015 . Borrowings under the 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) 150 basis points (in the case of a borrowing under the Revolving Credit Facility) or 175 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. In prior periods, the Company has had a $101.0 million loan agreement with unaffiliated banks dated as of October 30, 2009 , which had been amended at least annually between 2009 and 2014. The agreement consisted of a $100.0 million revolving credit facility, maturing on October 25, 2013 , and a $1.0 million term loan maturing on June 1, 2015 . In 2013, the Company repaid and terminated the $1.0 million term loan, and amended the agreement, effectively extending the maturity date on the revolving credit facility from October 25, 2013 to November 6, 2014 . The agreement was also amended in 2014 effectively extending the term to December 15, 2014 at which time the agreement matured. At September 30, 2014, no amount was outstanding on the $100.0 million revolving credit facility. Borrowings under the agreements 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 September 30, 2015 , 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. Securities Sold Under Repurchase Agreements At September 30, 2015 , December 31, 2014 and September 30, 2014 , securities sold under repurchase agreements represent $57.6 million , $48.6 million and $32.5 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 September 30, 2015 , the Company had pledged securities related to its customer balances in sweep accounts of $84.0 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, mortgage-backed and corporate securities. These securities are included in the available-for-sale securities portfolio as reflected on the Company’s Consolidated Statements of Condition. The following is a summary of these securities pledged disaggregated by investment category and maturity, and reconciled to the outstanding balance of securities sold under repurchase agreements: As of September 30, 2015 (Dollars in thousands) Overnight Sweep Collateral U.S. Treasury $ 10,003 U.S. Government agencies 2,867 Municipal 7,488 Corporate notes: Financial issuers 15,911 Mortgage-backed: Mortgage-backed securities 47,758 Total collateral pledged $ 84,027 Excess collateral 26,437 Securities sold under repurchase agreements $ 57,590 Other Borrowings Other borrowings at September 30, 2015 represent a fixed-rate promissory note issued by the Company in August 2012 ("Fixed-Rate Promissory Note") related to and secured by an office building owned by the Company. At September 30, 2015 , the Fixed-Rate Promissory Note had an outstanding balance of $18.5 million compared to an outstanding balance of $18.8 million and $19.0 million at December 31, 2014 and September 30, 2014, respectively. Under the Fixed-Rate Promissory Note, the Company will make monthly principal payments and pay interest at a fixed rate of 3.75% until maturity on September 1, 2017 . Secured Borrowings In December 2014, the Company, through its subsidiary, FIFC Canada, sold an undivided co-ownership interest in all receivables owed to FIFC Canada 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 proceeds received from the transaction are reflected on the Company’s Consolidated Statements of Condition as a secured borrowing owed to the unrelated third party and translated to the Company’s reporting currency as of the respective date. At September 30, 2015 the translated balance of the secured borrowing under the Receivable Purchase Agreement totaled $112.7 million compared to $129.1 million at December 31, 2014. Additionally, the interest rate under the Receivables Purchase Agreement at September 30, 2015 was 1.3865% . Subordinated Notes At September 30, 2015, December 31, 2014 and September 30, 2014, the Company had outstanding subordinated notes totaling $140.0 million . In the second quarter of 2014, the Company issued $140.0 million of subordinated notes receiving $139.1 million in net proceeds. The notes have a stated interest rate of 5.00% and mature in June 2024 .

Junior Subordinated Debentures

Junior Subordinated Debentures	9 Months Ended
	Sep. 30, 2015
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust [Abstract]
Junior Subordinated Debentures	Junior Subordinated Debentures As of September 30, 2015 , 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. 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 available-for-sale securities. The following table provides a summary of the Company’s junior subordinated debentures as of September 30, 2015 . The junior subordinated debentures represent the par value of the obligations owed to the Trusts. (Dollars in thousands) Common Securities Trust Preferred Securities Junior Subordinated Debentures Rate Structure Contractual rate at 9/30/2015 Issue Date Maturity Date Earliest Redemption Date Wintrust Capital Trust III $ 774 $ 25,000 $ 25,774 L+3.25 3.54 % 04/2003 04/2033 04/2008 Wintrust Statutory Trust IV 619 20,000 20,619 L+2.80 3.13 % 12/2003 12/2033 12/2008 Wintrust Statutory Trust V 1,238 40,000 41,238 L+2.60 2.93 % 05/2004 05/2034 06/2009 Wintrust Capital Trust VII 1,550 50,000 51,550 L+1.95 2.29 % 12/2004 03/2035 03/2010 Wintrust Capital Trust VIII 1,238 40,000 41,238 L+1.45 1.78 % 08/2005 09/2035 09/2010 Wintrust Capital Trust IX 1,547 50,000 51,547 L+1.63 1.97 % 09/2006 09/2036 09/2011 Northview Capital Trust I 186 6,000 6,186 L+3.00 3.30 % 08/2003 11/2033 08/2008 Town Bankshares Capital Trust I 186 6,000 6,186 L+3.00 3.30 % 08/2003 11/2033 08/2008 First Northwest Capital Trust I 155 5,000 5,155 L+3.00 3.33 % 05/2004 05/2034 05/2009 Suburban Illinois Capital Trust II 464 15,000 15,464 L+1.75 2.09 % 12/2006 12/2036 12/2011 Community Financial Shares Statutory Trust II 109 3,500 3,609 L+1.62 1.96 % 06/2007 09/2037 06/2012 Total $ 268,566 2.48 % The junior subordinated debentures totaled $268.6 million at September 30, 2015 compared to $249.5 million at December 31, 2014 and September 30, 2014 . 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 September 30, 2015 , the weighted average contractual interest rate on the junior subordinated debentures was 2.48% . The Company entered into interest rate swaps and caps with an aggregate notional value of $225 million to hedge the variable cash flows on certain junior subordinated debentures. The hedge-adjusted rate on the junior subordinated debentures as of September 30, 2015 , was 3.13% . 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 approval, if then required under applicable guidelines or regulations. Prior to January 1, 2015, the junior subordinated debentures, subject to certain limitations, qualified as Tier 1 regulatory capital of the Company and the amount in excess of those certain limitations could, subject to other restrictions, be included in Tier 2 capital. At December 31, 2014 and September 30, 2014, all of the junior subordinated debentures, net of the common securities, were included in the Company's Tier 1 regulatory capital. Starting in 2015, a portion of these junior subordinated debentures still qualified as Tier 1 regulatory capital of the Company and the amount in excess of those certain limitations, subject to certain restrictions, was included in Tier 2 capital. At September 30, 2015, $65.1 million and $195.4 million of the junior subordinated debentures, net of common securities, were included in the Company's Tier 1 and Tier 2 regulatory capital, respectively.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2015
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 originated by the specialty finance segment and sold 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 9 — 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 as those described in “Summary of Significant Accounting Policies” in Note 1 of the Company’s 2014 Form 10-K. 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: Three months ended $ Change in Contribution % Change in Contribution (Dollars in thousands) September 30, 2015 September 30, 2014 Net interest income: Community Banking $ 132,542 $ 121,998 $ 10,544 9 % Specialty Finance 24,657 21,903 2,754 13 Wealth Management 4,368 3,877 491 13 Total Operating Segments 161,567 147,778 13,789 9 Intersegment Eliminations 3,973 3,892 81 2 Consolidated net interest income $ 165,540 $ 151,670 $ 13,870 9 % Non-interest income: Community Banking $ 45,574 $ 38,274 $ 7,300 19 % Specialty Finance 8,264 8,320 (56 ) (1 ) Wealth Management 18,362 18,191 171 1 Total Operating Segments 72,200 64,785 7,415 11 Intersegment Eliminations (7,247 ) (6,833 ) (414 ) (6 ) Consolidated non-interest income $ 64,953 $ 57,952 $ 7,001 12 % Net revenue: Community Banking $ 178,116 $ 160,272 $ 17,844 11 % Specialty Finance 32,921 30,223 2,698 9 Wealth Management 22,730 22,068 662 3 Total Operating Segments 233,767 212,563 21,204 10 Intersegment Eliminations (3,274 ) (2,941 ) (333 ) (11 ) Consolidated net revenue $ 230,493 $ 209,622 $ 20,871 10 % Segment profit: Community Banking $ 22,723 $ 26,184 $ (3,461 ) (13 )% Specialty Finance 12,545 10,973 1,572 14 Wealth Management 3,087 3,067 20 1 Consolidated net income $ 38,355 $ 40,224 $ (1,869 ) (5 )% Segment assets: Community Banking $ 18,505,830 $ 15,945,744 $ 2,560,086 16 % Specialty Finance 2,987,236 2,704,591 282,645 10 Wealth Management 550,864 519,010 31,854 6 Consolidated total assets $ 22,043,930 $ 19,169,345 $ 2,874,585 15 % Nine months ended $ Change in Contribution % Change in Contribution (Dollars in thousands) September 30, 2015 September 30, 2014 Net interest income: Community Banking $ 382,187 $ 359,981 $ 22,206 6 % Specialty Finance 67,041 60,907 6,134 10 Wealth Management 12,837 11,982 855 7 Total Operating Segments 462,065 432,870 29,195 7 Intersegment Eliminations 12,258 11,986 272 2 Consolidated net interest income $ 474,323 $ 444,856 $ 29,467 7 % Non-interest income: Community Banking $ 146,739 $ 98,930 $ 47,809 48 % Specialty Finance 25,270 24,656 614 2 Wealth Management 56,103 54,367 1,736 3 Total Operating Segments 228,112 177,953 50,159 28 Intersegment Eliminations (21,605 ) (20,370 ) (1,235 ) (6 ) Consolidated non-interest income $ 206,507 $ 157,583 $ 48,924 31 % Net revenue: Community Banking $ 528,926 $ 458,911 $ 70,015 15 % Specialty Finance 92,311 85,563 6,748 8 Wealth Management 68,940 66,349 2,591 4 Total Operating Segments 690,177 610,823 79,354 13 Intersegment Eliminations (9,347 ) (8,384 ) (963 ) (11 ) Consolidated net revenue $ 680,830 $ 602,439 $ 78,391 13 % Segment profit: Community Banking $ 76,821 $ 73,393 $ 3,428 5 % Specialty Finance 34,875 30,257 4,618 15 Wealth Management 9,542 9,615 (73 ) (1 ) Consolidated net income $ 121,238 $ 113,265 $ 7,973 7 %

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2015
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) 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 and caps 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 has purchased interest rate cap derivatives to hedge or manage its own risk exposures. Certain interest rate cap derivatives have been designated as cash flow hedge derivatives of the variable cash outflows associated with interest expense on the Company’s junior subordinated debentures and certain deposits. Other cap derivatives are not designated for hedge accounting but are economic hedges of the Company's overall portfolio, therefore any mark to market changes in the value of these caps are recognized in earnings. Below is a summary of the interest rate cap derivatives held by the Company as of September 30, 2015 : (Dollars in thousands) Notional Accounting Fair Value as of Effective Date Maturity Date Amount Treatment September 30, 2015 May 3, 2012 May 3, 2016 215,000 Non-Hedge Designated — August 29, 2012 August 29, 2016 216,500 Cash Flow Hedging 5 February 22, 2013 August 22, 2016 43,500 Cash Flow Hedging 2 February 22, 2013 August 22, 2016 56,500 Non-Hedge Designated 2 March 21, 2013 March 21, 2017 100,000 Non-Hedge Designated 69 May 16, 2013 November 16, 2016 75,000 Non-Hedge Designated 13 September 15, 2013 September 15, 2017 50,000 Cash Flow Hedging 112 September 30, 2013 September 30, 2017 40,000 Cash Flow Hedging 97 $ 796,500 $ 300 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. 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, to the extent they are effective 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, including changes in fair value related to the ineffective portion of cash flow hedges, are reported in non-interest income during the period of the change. Derivative financial instruments are valued by a third party and are corroborated through 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 September 30, 2015 , December 31, 2014 and September 30, 2014 : Derivative Assets Derivative Liabilities Fair Value Fair Value (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 September 30, 2015 December 31, 2014 September 30, 2014 Derivatives designated as hedging instruments under ASC 815: Interest rate derivatives designated as Cash Flow Hedges $ 216 $ 1,390 $ 1,947 $ 1,329 $ 1,994 $ 2,202 Interest rate derivatives designated as Fair Value Hedges 5 52 79 291 — — Total derivatives designated as hedging instruments under ASC 815 $ 221 $ 1,442 $ 2,026 $ 1,620 $ 1,994 $ 2,202 Derivatives not designated as hedging instruments under ASC 815: Interest rate derivatives $ 56,717 $ 36,399 $ 31,249 $ 55,809 $ 34,927 $ 29,249 Interest rate lock commitments 11,836 10,028 10,010 — 20 31 Forward commitments to sell mortgage loans — 23 41 7,713 4,239 3,986 Foreign exchange contracts 260 72 17 56 — 37 Total derivatives not designated as hedging instruments under ASC 815 $ 68,813 $ 46,522 $ 41,317 $ 63,578 $ 39,186 $ 33,303 Total Derivatives $ 69,034 $ 47,964 $ 43,343 $ 65,198 $ 41,180 $ 35,505 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 and interest rate caps 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 caps designated as cash flow hedges involve the receipt of payments at the end of each period in which the interest rate specified in the contract exceeds the agreed upon strike price. During the first quarter of 2014, the Company designated two existing interest rate cap derivatives as cash flow hedges of variable rate deposits. The cap derivatives had notional amounts of $216.5 million and $43.5 million , respectively, both maturing in August 2016. Additionally, as of September 30, 2015 , the Company had two interest rate swaps and two interest rate caps designated as hedges of the variable cash outflows associated with interest expense on the Company’s junior subordinated debentures. The effective portion of changes in the fair value of these cash flow hedges is recorded in accumulated other comprehensive income and is subsequently reclassified to interest expense as interest payments are made on the Company’s variable rate junior subordinated debentures. The changes in fair value (net of tax) are separately disclosed in the Consolidated Statements of Comprehensive Income. The ineffective portion of the change in fair value of these derivatives is recognized directly in earnings; however, no hedge ineffectiveness was recognized during the nine months ended September 30, 2015 or September 30, 2014 . The Company uses the hypothetical derivative method to assess and measure hedge effectiveness. The table below provides details on each of these cash flow hedges as of September 30, 2015 : September 30, 2015 (Dollars in thousands) Notional Fair Value Maturity Date Amount Asset (Liability) Interest Rate Swaps: September 2016 50,000 (862 ) October 2016 25,000 (467 ) Total Interest Rate Swaps 75,000 (1,329 ) Interest Rate Caps: August 2016 43,500 2 August 2016 216,500 5 September 2017 50,000 112 September 2017 40,000 97 Total Interest Rate Caps 350,000 216 Total Cash Flow Hedges $ 425,000 $ (1,113 ) A rollforward of the amounts in accumulated other comprehensive loss related to interest rate derivatives designated as cash flow hedges follows: Three months ended Nine months ended (Dollars in thousands) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Unrealized loss at beginning of period $ (4,408 ) $ (4,695 ) $ (4,062 ) $ (3,971 ) Amount reclassified from accumulated other comprehensive loss to interest expense on deposits and junior subordinated debentures 571 553 1,460 1,567 Amount of loss recognized in other comprehensive income (503 ) 418 (1,738 ) (1,320 ) Unrealized loss at end of period $ (4,340 ) $ (3,724 ) $ (4,340 ) $ (3,724 ) As of September 30, 2015 , the Company estimates that during the next twelve months, $3.1 million will be reclassified from accumulated other comprehensive loss as an increase 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 September 30, 2015 , the Company has four interest rate swaps with an aggregate notional amount of $16.7 million that were designated as fair value hedges associated with fixed rate commercial and industrial and commercial franchise loans. For derivatives designated and that qualify as fair value hedges, the gain or loss on the derivative as well as the offsetting loss or gain on the hedged item attributable to the hedged risk are recognized in earnings. The Company includes the gain or loss on the hedged item in the same line item as the offsetting loss or gain on the related derivatives. The Company recognized a net loss of $21,000 in other income related to hedge ineffectiveness for the three months ended September 30, 2015 and no net gain or loss for the three months ended September 30, 2014 and a net loss of $23,000 and $3,000 for the respective year-to-date periods. On June 1, 2013, the Company de-designated a $96.5 million cap which was previously designated as a fair value hedge of interest rate risk associated with an embedded cap in one of the Company’s floating rate loans. The hedged loan was restructured which resulted in the interest rate cap no longer qualifying as an effective fair value hedge. As such, the interest rate cap derivative is no longer accounted for under hedge accounting and all changes in value subsequent to June 1, 2013 are recorded in earnings. Additionally, the Company has recorded amortization of the basis in the previously hedged item as a reduction to interest income of $43,000 and $129,000 in the three month and nine month periods ended September 30, 2015 and 2014, respectively. The following table presents the gain/(loss) and hedge ineffectiveness recognized on derivative instruments and the related hedged items that are designated as a fair value hedge accounting relationship as of September 30, 2015 and 2014: (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Recognized in Income on Derivative Three Months Ended Amount of (Loss)/Gain Recognized in Income on Hedged Item Three Months Ended Income Statement Gain/ (Loss) due to Hedge Ineffectiveness Three Months Ended September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Interest rate swaps Trading (losses) gains, net $ (323 ) $ 16 $ 302 $ (16 ) $ (21 ) $ — (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location of Gain/(Loss) Recognized in Income on Derivative Amount of Losses Recognized in Income on Derivative Nine Months Ended Amount of Gains Recognized in Income on Hedged Item Nine Months Ended Income Statement Losses due to Hedge Ineffectiveness Nine Months Ended September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Interest rate swaps Trading (losses) gains, net $ (338 ) $ (27 ) $ 315 $ 24 $ (23 ) $ (3 ) Non-Designated Hedges The Company does not use derivatives for speculative purposes. Derivatives not designated as hedges are used to manage the Company’s 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 non-interest income. At September 30, 2015 , the Company had interest rate derivative transactions with an aggregate notional amount of approximately $3.3 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 October 2015 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 September 30, 2015 , the Company had forward commitments to sell mortgage loans with an aggregate notional amount of approximately $731.1 million and interest rate lock commitments with an aggregate notional amount of approximately $455.7 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 September 30, 2015 the Company held foreign currency derivatives with an aggregate notional amount of approximately $16.3 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 hedges pursuant to ASC 815, and, accordingly, changes in fair value of these contracts are recognized in non-interest income. There were no covered call options outstanding as of September 30, 2015 , December 31, 2014 or September 30, 2014 . As discussed above, the Company has entered into interest rate cap derivatives to protect the Company in a rising rate environment against increased margin compression due to the repricing of variable rate liabilities and lack of repricing of fixed rate loans and/or securities. As of September 30, 2015 , the Company held four interest rate cap derivative contracts, which are not designated in hedge relationships, with an aggregate notional value of $446.5 million . Amounts included in the Consolidated Statements of Income related to derivative instruments not designated in hedge relationships were as follows: (Dollars in thousands) Three Months Ended Nine Months Ended Derivative Location in income statement September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Interest rate swaps and caps Trading (losses) gains, net $ (275 ) $ 270 $ (592 ) $ (1,144 ) Mortgage banking derivatives Mortgage banking revenue (4,062 ) (562 ) (1,669 ) (1,770 ) Covered call options Fees from covered call options 2,810 2,107 11,735 4,893 Foreign exchange contracts Trading (losses) gains, net 113 (12 ) 133 (23 ) 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 September 30, 2015 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 $58.5 million . If the Company had breached any of these provisions at September 30, 2015 it 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) September 30, 2015 December 31, 2014 September 30, 2014 September 30, 2015 December 31, 2014 September 30, 2014 Gross Amounts Recognized $ 56,938 $ 37,841 $ 33,275 $ 57,429 $ 36,921 $ 31,451 Less: Amounts offset in the Statements of Financial Condition — — — — — — Net amount presented in the Statements of Financial Condition $ 56,938 $ 37,841 $ 33,275 $ 57,429 $ 36,921 $ 31,451 Gross amounts not offset in the Statements of Financial Condition Offsetting Derivative Positions (614 ) (2,771 ) (5,417 ) (614 ) (2,771 ) (5,417 ) Collateral Posted (1) — — — (54,410 ) (34,150 ) (26,034 ) Net Credit Exposure $ 56,324 $ 35,070 $ 27,858 $ 2,405 $ — $ — (1) As of December 31, 2014 and September 30, 2014, the Company posted collateral of $43.8 million and $33.9 million , respectively, which resulted in excess collateral with its counterparties. For purposes of this disclosure, the amount of posted collateral is limited to the amount offsetting the derivative liability.

Fair Values of Assets and Liabi

Fair Values of Assets and Liabilities	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Values of Assets and Liabilities	Fair Values 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 assumptions 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 and trading account securities —Fair values for available-for-sale and trading securities 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 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 September 30, 2015 , the Company classified $68.4 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’s methodology for pricing the non-rated bonds 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 the third quarter of 2015, 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 September 30, 2015 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. At September 30, 2015 , the Company held $24.5 million of equity securities classified as Level 3. The securities in Level 3 are primarily comprised of auction rate preferred securities. The Company utilizes an independent pricing vendor to provide a fair market valuation of these securities. The vendor’s valuation methodology includes modeling the contractual cash flows of the underlying preferred securities and applying a discount to these cash flows by a credit spread derived from the market price of the securities underlying debt. At September 30, 2015 , the vendor considered five different securities whose implied credit spreads were believed to provide a proxy for the Company’s auction rate preferred securities. The credit spreads ranged from 2.01% - 2.43% with an average of 2.22% which was added to three-month LIBOR to be used as the discount rate input to the vendor’s model. Fair value of the securities is sensitive to the discount rate utilized as a higher discount rate results in a decreased fair value measurement. 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. Mortgage servicing rights —Fair value for mortgage servicing rights is determined utilizing a third party valuation model which stratifies the servicing rights into pools based on 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. At September 30, 2015 , the Company classified $7.9 million of mortgage servicing rights as Level 3. The weighted average discount rate used as an input to value the pool of mortgage servicing rights at September 30, 2015 was 9.15% with discount rates applied ranging from 9% - 13% . The higher the rate utilized to discount estimated future cash flows, the lower the fair value measurement. Additionally, fair value estimates include assumptions about prepayment speeds which ranged from 9% - 29% or a weighted average prepayment speed of 12.93% used as an input to value the pool of mortgage servicing rights at September 30, 2015 . Prepayment speeds are inversely related to the fair value of mortgage servicing rights as an increase in prepayment speeds results in a decreased valuation. Derivative instruments —The Company’s derivative instruments include interest rate swaps and caps, 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 and caps are valued by a third party, using models that primarily use market observable inputs, such as yield curves, and are corroborated 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. 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: September 30, 2015 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 285,922 $ — $ 285,922 $ — U.S. Government agencies 645,023 — 645,023 — Municipal 297,342 — 228,941 68,401 Corporate notes 116,945 — 116,945 — Mortgage-backed 815,045 — 815,045 — Equity securities 54,004 — 29,488 24,516 Trading account securities 3,312 — 3,312 — Mortgage loans held-for-sale 347,005 — 347,005 — Mortgage servicing rights 7,875 — — 7,875 Nonqualified deferred compensation assets 8,342 — 8,342 — Derivative assets 69,034 — 69,034 — Total $ 2,649,849 $ — $ 2,549,057 $ 100,792 Derivative liabilities $ 65,198 $ — $ 65,198 $ — December 31, 2014 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 381,805 $ — $ 381,805 $ — U.S. Government agencies 668,316 — 668,316 — Municipal 238,529 — 179,576 58,953 Corporate notes 133,579 — 133,579 — Mortgage-backed 318,710 — 318,710 — Equity securities 51,139 — 27,428 23,711 Trading account securities 1,206 — 1,206 — Mortgage loans held-for-sale 351,290 — 351,290 — Mortgage servicing rights 8,435 — — 8,435 Nonqualified deferred compensation assets 7,951 — 7,951 — Derivative assets 47,964 — 47,964 — Total $ 2,208,924 $ — $ 2,117,825 $ 91,099 Derivative liabilities $ 41,180 $ — $ 41,180 $ — September 30, 2014 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 378,261 $ — $ 378,261 $ — U.S. Government agencies 739,752 — 739,752 — Municipal 187,103 — 136,866 50,237 Corporate notes 134,155 — 134,155 — Mortgage-backed 291,222 — 291,222 — Equity securities 52,155 — 28,194 23,961 Trading account securities 6,015 — 6,015 — Mortgage loans held-for-sale 363,303 — 363,303 — Mortgage servicing rights 8,137 — — 8,137 Nonqualified deferred compensation assets 7,927 — 7,927 — Derivative assets 43,343 — 43,343 — Total $ 2,211,373 $ — $ 2,129,038 $ 82,335 Derivative liabilities $ 35,505 $ — $ 35,505 $ — The aggregate remaining contractual principal balance outstanding as of September 30, 2015 , December 31, 2014 and September 30, 2014 for mortgage loans held-for-sale measured at fair value under ASC 825 was $328.1 million , $327.1 million and $340.0 million , respectively, while the aggregate fair value of mortgage loans held-for-sale was $347.0 million , $351.3 million and $363.3 million , for the same respective periods, as shown in the above tables. There were no nonaccrual loans or loans past due greater than 90 days and still accruing in the mortgage loans held-for-sale portfolio measured at fair value as of September 30, 2015 , December 31, 2014 and September 30, 2014 . The changes in Level 3 assets measured at fair value on a recurring basis during the three and nine months ended September 30, 2015 and 2014 are summarized as follows: Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at July 1, 2015 $ 58,572 $ 24,996 $ 8,034 Total net gains (losses) included in: Net income (1) — — (159 ) Other comprehensive income 223 (480 ) — Purchases 10,405 — — Issuances — — — Sales — — — Settlements (799 ) — — Net transfers into/(out of) Level 3 — — — Balance at September 30, 2015 $ 68,401 $ 24,516 $ 7,875 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at January 1, 2015 $ 58,953 $ 23,711 $ 8,435 Total net gains (losses) included in: Net income (1) — — (560 ) Other comprehensive income (287 ) 805 — Purchases 21,254 — — Issuances — — — Sales — — — Settlements (11,519 ) — — Net transfers into/(out of) Level 3 — — — Balance at September 30, 2015 $ 68,401 $ 24,516 $ 7,875 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at July 1, 2014 $ 38,053 $ 24,152 $ 8,227 Total net gains (losses) included in: Net income (1) — — (90 ) Other comprehensive income (27 ) (191 ) — Purchases 4,129 — — Issuances — — — Sales — — — Settlements (800 ) — — Net transfers into/(out of) Level 3 (2) 8,882 — — Balance at September 30, 2014 $ 50,237 $ 23,961 $ 8,137 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. (2) Transfers into Level 3 relate to a reclassification of municipal bonds in the current quarter. Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at January 1, 2014 $ 36,386 $ 22,163 $ 8,946 Total net gains (losses) included in: Net income (1) — — (809 ) Other comprehensive income 193 1,798 — Purchases 9,095 — — Issuances — — — Sales — — — Settlements (4,319 ) — — Net transfers into/(out of) Level 3 (2) 8,882 — — Balance at September 30, 2014 $ 50,237 $ 23,961 $ 8,137 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. (2) Transfers into Level 3 relate to a reclassification of municipal bonds in the current quarter. 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 September 30, 2015 . September 30, 2015 Three Months Ended September 30, 2015 Fair Value Losses Recognized, net Nine Months Ended September 30, 2015 Fair Value Losses Recognized, net (Dollars in thousands) Total Level 1 Level 2 Level 3 Impaired loans—collateral based $ 73,819 $ — $ — $ 73,819 $ 5,262 $ 11,517 Other real estate owned, including covered other real estate owned (1) 80,524 — — 80,524 989 4,834 Total $ 154,343 $ — $ — $ 154,343 $ 6,251 $ 16,351 (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 restructured in a troubled debt restructuring 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 representing the estimated cost of sale, 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 7 – Allowance for Loan Losses, Allowance for Losses on Lending-Related Commitments and Impaired Loans. At September 30, 2015 , the Company had $113.0 million of impaired loans classified as Level 3. Of the $113.0 million of impaired loans, $73.8 million were measured at fair value based on the underlying collateral of the loan as shown in the table above. The remaining $39.2 million were valued based on discounted cash flows in accordance with ASC 310. Other real estate owned (including covered 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 non-covered other real estate owned and covered other real estate owned. At September 30, 2015 , the Company had $80.5 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 September 30, 2015 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 $ 68,401 Bond pricing Equivalent rating BBB-AA+ N/A Increase Equity Securities 24,516 Discounted cash flows Discount rate 2.01%-2.43% 2.22% Decrease Mortgage Servicing Rights 7,875 Discounted cash flows Discount rate 9%-13% 9.15% Decrease Constant prepayment rate (CPR) 9%-29% 12.93% Decrease Measured at fair value on a non-recurring basis: Impaired loans—collateral based $ 73,819 Appraisal value Appraisal adjustment - cost of sale 10% 10.00% Decrease Other real estate owned, including covered other real estate owned 80,524 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: At September 30, 2015 At December 31, 2014 At September 30, 2014 Carrying Fair Carrying Fair Carrying Fair (Dollars in thousands) Value Value Value Value Value Value Financial Assets: Cash and cash equivalents $ 250,655 $ 250,655 $ 230,707 $ 230,707 $ 287,416 $ 287,416 Interest bearing deposits with banks 701,106 701,106 998,437 998,437 620,370 620,370 Available-for-sale securities 2,214,281 2,214,281 1,792,078 1,792,078 1,782,648 1,782,648 Trading account securities 3,312 3,312 1,206 1,206 6,015 6,015 Federal Home Loan Bank and Federal Reserve Bank stock, at cost 90,308 90,308 91,582 91,582 80,951 80,951 Brokerage customer receivables 28,293 28,293 24,221 24,221 26,624 26,624 Mortgage loans held-for-sale, at fair value 347,005 347,005 351,290 351,290 363,303 363,303 Total loans 16,484,820 17,284,375 14,636,107 15,346,266 14,306,664 15,001,394 Mortgage servicing rights 7,875 7,875 8,435 8,435 8,137 8,137 Nonqualified deferred compensation assets 8,342 8,342 7,951 7,951 7,927 7,927 Derivative assets 69,034 69,034 47,964 47,964 43,343 43,343 FDIC indemnification asset — — 11,846 11,846 27,359 27,359 Accrued interest receivable and other 192,572 192,572 169,156 169,156 170,517 170,517 Total financial assets $ 20,397,603 $ 21,197,158 $ 18,370,980 $ 19,081,139 $ 17,731,274 $ 18,426,004 Financial Liabilities Non-maturity deposits $ 14,092,697 $ 14,092,697 $ 12,142,034 $ 12,142,034 $ 11,761,825 $ 11,761,825 Deposits with stated maturities 4,135,772 4,137,856 4,139,810 4,143,161 4,303,421 4,303,717 Federal Home Loan Bank advances 451,330 459,154 733,050 738,113 347,500 352,516 Other borrowings 259,978 259,978 196,465 197,883 51,483 51,483 Subordinated notes 140,000 142,953 140,000 143,639 140,000 142,720 Junior subordinated debentures 268,566 268,058 249,493 250,305 249,493 250,452 Derivative liabilities 65,198 65,198 41,180 41,180 35,505 35,505 Accrued interest payable 11,364 11,364 8,001 8,001 8,995 8,995 Total financial liabilities $ 19,424,905 $ 19,437,258 $ 17,650,033 $ 17,664,316 $ 16,898,222 $ 16,907,213 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 asset, 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. Loans. 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. The primary impact of credit risk on the present value of the loan portfolio, however, was assessed through the use of the allowance for loan losses, which is believed to represent the current fair value of probable incurred losses for purposes of the fair value calculation. 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. Federal Home Loan Bank advances. The fair value of Federal Home Loan Bank advances is obtained from the Federal Home Loan Bank 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 Federal Home Loan Bank 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.

Stock-Based Compensation Plans

Stock-Based Compensation Plans	9 Months Ended
	Sep. 30, 2015
Share-based Compensation [Abstract]
Stock-Based Compensation Plans	Stock-Based Compensation Plans 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. Outstanding awards 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 will be made pursuant to the 2015 Plan. 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 settled in shares of common stock and other incentive awards based in whole or in part by reference to the Company’s common stock. The Company historically awarded stock-based compensation in the form of time-vested non-qualified stock options and time-vested restricted share unit awards (“restricted shares”). The grants of options provide for the purchase of shares of the Company’s common stock at the fair market value of the stock on the date the options are granted. Stock 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. Stock options granted under the 1997 Plan provided for a maximum term of 10 years. 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 the interests of shareholders, foster retention, create a long-term focus based on sustainable results and provide participants with 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 non-qualified stock options and performance-based stock and cash awards. 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 starting at the beginning of each calendar year. 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 a maximum of 150% (for 2015 awards) or 200% (for prior awards) of the target award. The awards 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 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. Except in limited circumstances, these awards 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. Expected life of 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 The following table presents the weighted average assumptions used to determine the fair value of options granted in the nine month periods ending September 30, 2015 and 2014 . Nine Months Ended September 30, September 30, 2015 2014 Expected dividend yield 0.9 % 0.4 % Expected volatility 26.5 % 30.8 % Risk-free rate 1.3 % 0.7 % Expected option life (in years) 4.5 4.5 Stock based compensation is recognized based upon the number of awards that are ultimately expected to vest, taking into account expected forfeitures. In addition, for performance-based awards, an estimate is made of the number of shares expected to vest as a result of projected performance against the performance criteria in the award to determine the amount of compensation expense to recognize. The estimate is reevaluated periodically and total compensation expense is adjusted for any change in estimate in the current period. Stock-based compensation expense recognized in the Consolidated Statements of Income was $2.5 million in the third quarter of 2015 and $2.2 million in the third quarter of 2014, and $7.8 million and $8.1 million for the year-to-date periods, respectively. The first quarter of 2014 included a $2.1 million charge for a modification to the performance measurement criteria related to the 2011 LTIP performance-based stock grants that were vested and paid out in the first quarter of 2014. The cost of the modification was determined based on the stock price on the date of re-measurement and paid to the holders of the performance-based stock awards in cash. A summary of the Company's stock option activity for the nine months ended September 30, 2015 and September 30, 2014 is presented below: Stock Options Common Shares Weighted Average Strike Price Remaining Contractual Term (1) Intrinsic Value (2) ($000) Outstanding at January 1, 2015 1,618,426 $ 43.00 Conversion of options of acquired company 16,364 21.18 Granted 502,517 44.36 Exercised (258,836 ) 43.14 Forfeited or canceled (277,150 ) 53.64 Outstanding at September 30, 2015 1,601,321 $ 41.34 4.7 $ 19,378 Exercisable at September 30, 2015 715,101 $ 37.52 3.2 $ 11,376 Stock Options Common Shares Weighted Average Strike Price Remaining Contractual Term (1) Intrinsic Value (2) ($000) Outstanding at January 1, 2014 1,524,672 $ 42.00 Granted 366,478 46.85 Exercised (139,928 ) 33.90 Forfeited or canceled (99,147 ) 50.61 Outstanding at September 30, 2014 1,652,075 $ 43.24 3.4 $ 8,133 Exercisable at September 30, 2014 1,050,665 $ 43.86 2.1 $ 5,851 (1) Represents the remaining weighted average contractual life in years. (2) Aggregate intrinsic value represents the total pre-tax intrinsic value (i.e., the difference between the Company's stock price on the last trading day of the quarter 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 quarter. Options with exercise prices above the stock price on the last trading day of the quarter 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 grant date fair value per share of options granted during the nine months ended September 30, 2015 and September 30, 2014 was $9.72 and $11.96 , respectively. The aggregate intrinsic value of options exercised during the nine months ended September 30, 2015 and 2014, was $2.3 million and $1.8 million , respectively. A summary of the Plans' restricted share activity for the nine months ended September 30, 2015 and September 30, 2014 is presented below: Nine months ended September 30, 2015 Nine months ended September 30, 2014 Restricted Shares Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Outstanding at January 1 146,112 $ 47.45 181,522 $ 43.39 Granted 15,657 45.81 12,313 46.04 Vested and issued (20,409 ) 39.07 (51,978 ) 35.12 Forfeited (2,400 ) 36.81 (6,752 ) 37.95 Outstanding at September 30 138,960 $ 48.68 135,105 $ 47.09 Vested, but not issuable at September 30 85,000 $ 51.88 85,000 $ 51.88 A summary of the Plans' performance-based stock award activity, based on the target level of the awards, for the nine months ended September 30, 2015 and September 30, 2014 is presented below: Nine months ended September 30, 2015 Nine months ended September 30, 2014 Performance-based Stock Common Weighted Common Weighted Outstanding at January 1 295,679 $ 38.18 307,512 $ 34.01 Granted 106,017 44.35 93,535 46.85 Vested and issued (78,590 ) 31.10 (15,944 ) 33.25 Forfeited (33,854 ) 32.74 (89,424 ) 33.78 Outstanding at September 30 289,252 $ 43.00 295,679 $ 38.18 The Company issues new shares to satisfy its obligation to issue shares granted pursuant to the Plans.

Shareholders' Equity and Earnin

Shareholders' Equity and Earnings Per Share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]
Shareholders' Equity and Earnings Per Share	Shareholders’ Equity and Earnings Per Share Series D Preferred Stock In June 2015, the Company issued and sold 5,000,000 shares of fixed-to-floating non-cumulative perpetual preferred stock, Series D, liquidation preference $25 per share (the “Series D Preferred Stock”) for $125.0 million in an equity offering. 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. Series C Preferred Stock In March 2012, the Company issued and sold 126,500 shares of non-cumulative perpetual convertible preferred stock, Series C, liquidation preference $1,000 per share (the “Series C Preferred Stock”) for $126.5 million in an equity offering. If declared, dividends on the Series C Preferred Stock are payable quarterly in arrears at a rate of 5.00% per annum. The Series C Preferred Stock is convertible into common stock at the option of the holder at a conversion rate of 24.3132 shares of common stock per share of Series C Preferred Stock subject to customary anti-dilution adjustments. In the first nine months of 2015, pursuant to such terms, 155 shares of the Series C Preferred Stock were converted at the option of the respective holders into 3,767 shares of the Company's common stock. In 2014, 10 shares of the Series C Preferred Stock were converted at the option of the respective holders into 244 shares of the Company's common stock. On and after April 15, 2017, the Company will have the right under certain circumstances to cause the Series C Preferred Stock to be converted into common stock if the closing price of the Company’s common stock exceeds a certain amount. Common Stock Warrant 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 at a per share exercise price of $22.82 , subject to customary anti-dilution adjustments, and 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 the first nine months of 2015, certain holders of the interest in the warrant exercised 554,065 warrant shares at the exercise price, which resulted in 304,915 shares of common stock issued. At September 30, 2015, all remaining holders of the interest in the warrant are able to exercise 383,352 warrant shares. Other In July 2015, the Company issued 388,573 shares of its common stock in the acquisition of CFIS. In January 2015, the Company issued 422,122 shares of its common stock in the acquisition of Delavan. At the January 2015 Board of Directors meeting, a quarterly cash dividend of $0.11 per share ( $0.44 on an annualized basis) was declared. It was paid on February 19, 2015 to shareholders of record as of February 5, 2015 . At the April 2015 Board of Directors meeting, a quarterly cash dividend of $0.11 per share ( $0.44 on an annualized basis) was declared. It was paid on May 21, 2015 to shareholders of record as of May 7, 2015 . At the July 2015 Board of Directors meeting, a quarterly cash dividend of $0.11 per share ( $0.44 on an annualized basis) was declared. It was paid on August 20, 2015 to shareholders of record as of August 6, 2015 . Accumulated Other Comprehensive Income (Loss) The following tables summarize the components of other comprehensive income (loss), including the related income tax effects, and the related amount reclassified to net income for the periods presented (in thousands). Accumulated Unrealized Gains (Losses) on Securities Accumulated Unrealized Losses on Derivative Instruments Accumulated Foreign Currency Translation Adjustments Total Accumulated Other Comprehensive Loss Balance at July 1, 2015 $ (26,333 ) $ (2,727 ) $ (32,811 ) $ (61,871 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 18,995 (287 ) (6,337 ) 12,371 Amount reclassified from accumulated other comprehensive income (loss), net of tax 60 347 — 407 Net other comprehensive income (loss) during the period, net of tax $ 19,055 $ 60 $ (6,337 ) $ 12,778 Balance at September 30, 2015 $ (7,278 ) $ (2,667 ) $ (39,148 ) $ (49,093 ) Balance at January 1, 2015 $ (9,533 ) $ (2,517 ) $ (25,282 ) $ (37,332 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 2,499 (1,027 ) (13,866 ) (12,394 ) Amount reclassified from accumulated other comprehensive income (loss), net of tax (244 ) 877 — 633 Net other comprehensive income (loss) during the period, net of tax $ 2,255 $ (150 ) $ (13,866 ) $ (11,761 ) Balance at September 30, 2015 $ (7,278 ) $ (2,667 ) $ (39,148 ) $ (49,093 ) Balance at July 1, 2014 $ (24,003 ) $ (2,898 ) $ (7,602 ) $ (34,503 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 812 252 (9,685 ) (8,621 ) Amount reclassified from accumulated other comprehensive income (loss), net of tax 91 333 — 424 Net other comprehensive income (loss) during the period, net of tax $ 903 $ 585 $ (9,685 ) $ (8,197 ) Balance at September 30, 2014 $ (23,100 ) $ (2,313 ) $ (17,287 ) $ (42,700 ) Balance at January 1, 2014 $ (53,665 ) $ (2,462 ) $ (6,909 ) $ (63,036 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 30,251 (795 ) (10,378 ) 19,078 Amount reclassified from accumulated other comprehensive income (loss), net of tax 314 944 — 1,258 Net other comprehensive income (loss) during the period, net of tax $ 30,565 $ 149 $ (10,378 ) $ 20,336 Balance at September 30, 2014 $ (23,100 ) $ (2,313 ) $ (17,287 ) $ (42,700 ) Amount Reclassified from Accumulated Other Comprehensive Income for the Details Regarding the Component of Accumulated Other Comprehensive Income Three Months Ended Nine Months Ended Impacted Line on the Consolidated Statements of Income September 30, September 30, 2015 2014 2015 2014 Accumulated unrealized losses on securities (Losses) gains included in net income $ (98 ) $ (153 ) $ 402 $ (522 ) (Losses) gains on available-for-sale securities, net (98 ) (153 ) 402 (522 ) Income before taxes Tax effect $ 38 $ 62 $ (158 ) $ 208 Income tax expense Net of tax $ (60 ) $ (91 ) $ 244 $ (314 ) Net income Accumulated unrealized losses on derivative instruments Amount reclassified to interest expense on deposits $ 92 $ — $ 92 $ — Interest on deposits Amount reclassified to interest expense on junior subordinated debentures 479 553 $ 1,350 $ 1,567 Interest on junior subordinated debentures (571 ) (553 ) (1,442 ) (1,567 ) Income before taxes Tax effect $ 224 $ 220 $ 565 $ 623 Income tax expense Net of tax $ (347 ) $ (333 ) $ (877 ) $ (944 ) Net income Earnings per Share The following table shows the computation of basic and diluted earnings per share for the periods indicated: Three Months Ended Nine Months Ended (In thousands, except per share data) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Net income $ 38,355 $ 40,224 $ 121,238 $ 113,265 Less: Preferred stock dividends and discount accretion 4,079 1,581 7,240 4,743 Net income applicable to common shares—Basic (A) 34,276 38,643 113,998 108,522 Add: Dividends on convertible preferred stock, if dilutive 1,579 1,581 4,740 4,743 Net income applicable to common shares—Diluted (B) 35,855 40,224 118,738 113,265 Weighted average common shares outstanding (C) 48,158 46,639 47,658 46,453 Effect of dilutive potential common shares Common stock equivalents 978 1,166 1,070 1,274 Convertible preferred stock, if dilutive 3,071 3,075 3,071 3,075 Total dilutive potential common shares 4,049 4,241 4,141 4,349 Weighted average common shares and effect of dilutive potential common shares (D) 52,207 50,880 51,799 50,802 Net income per common share: Basic (A/C) $ 0.71 $ 0.83 $ 2.39 $ 2.34 Diluted (B/D) $ 0.69 $ 0.79 $ 2.29 $ 2.23 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 Employee Stock Purchase Plan and the Directors Deferred Fee and Stock 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.

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Basis of Accounting, Policy	The consolidated financial statements of Wintrust Financial Corporation and Subsidiaries (“Wintrust” or “the Company”) presented herein are unaudited, but in the opinion of management reflect all necessary adjustments of a normal or recurring nature for a fair presentation of results as of the dates and for the periods covered by the consolidated financial statements. The accompanying consolidated financial statements are unaudited and do not include information or footnotes necessary for a complete presentation of financial condition, results of operations or cash flows in accordance with U.S. generally accepted accounting principles ("GAAP"). The consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014 (“ 2014 Form 10-K”). Operating results reported for the three-month and nine-month periods are not necessarily indicative of the results which may be expected for the entire year. Reclassifications of certain prior period amounts have been made to conform to the current period presentation. The preparation of the financial statements requires management to make estimates, assumptions and judgments that affect the reported amounts of assets and liabilities. Management believes that the estimates made are reasonable, however, changes in estimates may be required if economic or other conditions develop differently from management’s expectations. Certain policies and accounting principles inherently have a greater reliance on the use of estimates, assumptions and judgments and as such have a greater possibility of producing results that could be materially different than originally reported. Management views critical accounting policies to be those which are highly dependent on subjective or complex judgments, estimates and assumptions, and where changes in those estimates and assumptions could have a significant impact on the financial statements. Management currently views the determination of the allowance for loan losses, allowance for covered loan losses and the allowance for losses on lending-related commitments, loans acquired with evidence of credit quality deterioration since origination, estimations of fair value, the valuations required for impairment testing of goodwill, the valuation and accounting for derivative instruments and income taxes as the accounting areas that require the most subjective and complex judgments, and as such could be the most subject to revision as new information becomes available. Descriptions of our significant accounting policies are included in Note 1 - “Summary of Significant Accounting Policies” of the Company’s 2014 Form 10-K.
Income Tax, Policy	Accounting for Investments in Qualified Affordable Housing Projects In January 2014, the FASB issued ASU No. 2014-01, “Investments - Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects,” to provide guidance on accounting for investments by a reporting entity in flow-through limited liability entities that invest in affordable housing projects that qualify for the low-income housing tax credit. This ASU permits a new accounting treatment, if certain conditions are met, which allows the Company to amortize the initial cost of an investment in proportion to the amount of tax credits and other tax benefits received with recognition of the investment performance in income tax expense. The Company adopted this new guidance beginning January 1, 2015. The guidance did not have a material impact on the Company's consolidated financial statements.
Loans and Leases Receivable, Troubled Debt Restructuring, Policy	Repossession of Residential Real Estate Collateral In January 2014, the FASB issued ASU No. 2014-04, “Receivables - Troubled Debt Restructurings by Creditors (Topic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure,” to address diversity in practice and clarify guidance regarding the accounting for an in-substance repossession or foreclosure of residential real estate collateral. This ASU clarifies that an in-substance repossession or foreclosure occurs upon either the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or the borrower conveying all interest in the residential real estate property to the creditor. Additionally, this ASU requires disclosure of both the amount of foreclosed residential real estate property held by the Company and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure. The Company adopted this new guidance beginning January 1, 2015. The guidance did not have a material impact on the Company's consolidated financial statements. 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 six or worse or a modification of any other credit which will result in a restructured credit risk rating of six 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 five 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 five 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 at any subsequent re-modification 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 the 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 September 30, 2015 and approximately $3.4 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. During the three months ended September 30, 2015 and 2014, the Company recorded $98,000 and $294,000 , respectively, in interest income representing this decrease in impairment. For the nine months ended September 30, 2015 and 2014, the Company recorded $385,000 and $529,000 , respectively, to interest income representing the reduction 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. Excluding covered OREO, at September 30, 2015 , the Company had $15.7 million of foreclosed residential real estate properties included within OREO.
FDIC-Assisted Transactions, Policy	Since 2010, 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 comprise the majority of the assets acquired in nearly all of these FDIC-assisted transactions, most of which are subject to loss sharing agreements with the FDIC whereby the FDIC has 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 require the Company to reimburse the FDIC in the event that actual losses on covered assets are 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. The agreements with the FDIC require that the Company follow certain servicing procedures or risk losing the FDIC reimbursement of covered asset losses. The loans covered by the loss sharing agreements are classified and presented as covered loans and the estimated reimbursable losses are recorded as an FDIC indemnification asset 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 will only recognize a provision for credit losses and charge-offs on the acquired loans for any further credit deterioration subsequent to the acquisition date. See Note 7 — 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 cover realized losses on loans, foreclosed real estate and certain other assets and require the Company to record loss share assets and liabilities that are measured separately from the loan portfolios because they are not contractually embedded in the loans and are 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 are recorded as FDIC indemnification assets and other liabilities, respectively, on the Consolidated Statements of Condition. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses will reduce the FDIC indemnification assets. Reductions to expected losses, to the extent such reductions to expected losses are the result of an improvement to the actual or expected cash flows from the covered assets, will also reduce the FDIC indemnification assets and, if necessary, increase any loss share liability when necessary reductions exceed the current value of the FDIC indemnification assets. In accordance with the clawback provision noted above, the Company may be required to reimburse the FDIC when actual losses are less than certain thresholds established for each lose share agreement. The balance of these estimated reimbursements in accordance with clawback provisions and any related amortization are adjusted periodically for changes in the expected losses on covered assets. On the Consolidated Statements of Condition, estimated reimbursements from clawback provisions are recorded as a reduction to the FDIC indemnification asset or, if necessary, an increase to the loss share liability, which is included within accrued interest payable and other liabilities. Although these assets are contractual receivables from the FDIC, there are no contractual interest rates. Additional expected losses, to the extent such expected losses result in recognition of an allowance for covered loan losses, will increase the FDIC indemnification asset. The corresponding amortization is recorded as a component of non-interest income on the Consolidated Statements of Income.
Purchased Credit Impaired (PCI) Loans, Policy	Purchased loans acquired in a business combination are recorded at estimated fair value on their purchase date. 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 generally 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 with the accretable component being recognized into interest income using the effective yield method over the estimated remaining life of the loans. The non-accretable portion is evaluated each quarter and if the loans’ credit related conditions improve, a portion is transferred to the accretable component and accreted over future periods. In the event a specific loan prepays in whole, any remaining accretable and non-accretable discount is recognized in income immediately. If credit related conditions deteriorate, an allowance related to these loans will be established as part of the provision for credit losses.
Cash and Cash Equivalents, Policy	For purposes of the Consolidated Statements of Cash Flows, the Company considers cash and cash equivalents to include 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.
Available-for-sale Securities, Policy	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 September 30, 2015 to be other-than-temporarily impaired.
Finance, Loans and Leases Receivable, Policy	Certain premium finance receivables are recorded net of unearned income. The unearned income portions of such premium finance receivables were $53.4 million at September 30, 2015 , $46.9 million at December 31, 2014 and $44.8 million at September 30, 2014 , respectively. Certain life insurance premium finance receivables attributable to the life insurance premium finance loan acquisition in 2009 as well as PCI loans are recorded net of credit discounts.
Receivables, Policy	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 and Nonperforming Loans, Allowance Policy	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 we determine 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, Policy	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 and covered loans. The remainder of the portfolio is considered performing under the contractual terms of the loan agreement.
Loans and Leases Receivable, Allowance for Loan Losses, Policy	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 result in the recognition of an allowance for loan losses, will increase the FDIC indemnification asset. The allowance for loan losses for loans acquired in FDIC-assisted transactions is 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 is 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 are the result of an improvement to the actual or expected cash flows from the covered assets, will reduce the FDIC indemnification asset. Additions to expected losses will require an increase to the allowance for loan losses, and a corresponding increase to the FDIC indemnification asset.
Impaired Financing Receivable, Policy	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. 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. 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 restructured in a troubled debt restructuring 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 representing the estimated cost of sale, are generally used on real estate collateral-dependent impaired loans.
Goodwill and Intangible Assets, Goodwill, Policy	At June 30, 2015, the Company utilized a qualitative approach for its annual goodwill impairment test of the community banking segment and determined that it is not more likely than not that an impairment existed at that time. The annual goodwill impairment tests of the specialty finance and wealth management segments will be conducted at December 31, 2015.
Goodwill and Intangible Assets, Intangible Assets, Policy	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 ten -year period on a straight-line basis.
Debt, Policy	FHLB advances are stated at par value of the debt adjusted for unamortized fair value adjustments recorded in connection with advances acquired through acquisitions. The proceeds received from the transaction are reflected on the Company’s Consolidated Statements of Condition as a secured borrowing owed to the unrelated third party and translated to the Company’s reporting currency as of the respective date.
Offsetting Assets and Liabilities, Policy	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, Policy	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, mortgage-backed and corporate securities. These securities are included in the available-for-sale securities portfolio as reflected on the Company’s Consolidated Statements of Condition.
Junior Subordinated Debentures, Policy	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 available-for-sale securities.
Segment Reporting, Policy	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 originated by the specialty finance segment and sold 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 9 — 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 as those described in “Summary of Significant Accounting Policies” in Note 1 of the Company’s 2014 Form 10-K. The Company evaluates segment performance based on after-tax profit or loss and other appropriate profitability measures common to each segment.
Derivatives, Policy	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. On June 1, 2013, the Company de-designated a $96.5 million cap which was previously designated as a fair value hedge of interest rate risk associated with an embedded cap in one of the Company’s floating rate loans. The hedged loan was restructured which resulted in the interest rate cap no longer qualifying as an effective fair value hedge. As such, the interest rate cap derivative is no longer accounted for under hedge accounting and all changes in value subsequent to June 1, 2013 are recorded in earnings. Additionally, the Company has recorded amortization of the basis in the previously hedged item as a reduction to interest income of $43,000 and $129,000 in the three month and nine month periods ended September 30, 2015 and 2014, respectively. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings. 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. 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, to the extent they are effective 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, including changes in fair value related to the ineffective portion of cash flow hedges, are reported in non-interest income during the period of the change. Derivative financial instruments are valued by a third party and are corroborated through 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 effective portion of changes in the fair value of these cash flow hedges is recorded in accumulated other comprehensive income and is subsequently reclassified to interest expense as interest payments are made on the Company’s variable rate junior subordinated debentures. The changes in fair value (net of tax) are separately disclosed in the Consolidated Statements of Comprehensive Income. The ineffective portion of the change in fair value of these derivatives is recognized directly in earnings; however, no hedge ineffectiveness was recognized during the nine months ended September 30, 2015 or September 30, 2014 . The Company uses the hypothetical derivative method to assess and measure hedge effectiveness. 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 hedges pursuant to ASC 815, and, accordingly, changes in fair value of these contracts are recognized in non-interest income. 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 non-interest income. For derivatives designated and that qualify as fair value hedges, the gain or loss on the derivative as well as the offsetting loss or gain on the hedged item attributable to the hedged risk are recognized in earnings. The Company includes the gain or loss on the hedged item in the same line item as the offsetting loss or gain on the related derivatives. The Company recognized a net loss of $21,000 in other income related to hedge ineffectiveness for the three months ended September 30, 2015 and no net gain or loss for the three months ended September 30, 2014 and a net loss of $23,000 and $3,000 for the respective year-to-date periods.
Derivatives, Offsetting Fair Value Amounts, Policy	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, Policy	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 assumptions 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 and trading account securities —Fair values for available-for-sale and trading securities 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 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 September 30, 2015 , the Company classified $68.4 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’s methodology for pricing the non-rated bonds 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 the third quarter of 2015, 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 September 30, 2015 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. At September 30, 2015 , the Company held $24.5 million of equity securities classified as Level 3. The securities in Level 3 are primarily comprised of auction rate preferred securities. The Company utilizes an independent pricing vendor to provide a fair market valuation of these securities. The vendor’s valuation methodology includes modeling the contractual cash flows of the underlying preferred securities and applying a discount to these cash flows by a credit spread derived from the market price of the securities underlying debt. At September 30, 2015 , the vendor considered five different securities whose implied credit spreads were believed to provide a proxy for the Company’s auction rate preferred securities. The credit spreads ranged from 2.01% - 2.43% with an average of 2.22% which was added to three-month LIBOR to be used as the discount rate input to the vendor’s model. Fair value of the securities is sensitive to the discount rate utilized as a higher discount rate results in a decreased fair value measurement. 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. Mortgage servicing rights —Fair value for mortgage servicing rights is determined utilizing a third party valuation model which stratifies the servicing rights into pools based on 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. At September 30, 2015 , the Company classified $7.9 million of mortgage servicing rights as Level 3. The weighted average discount rate used as an input to value the pool of mortgage servicing rights at September 30, 2015 was 9.15% with discount rates applied ranging from 9% - 13% . The higher the rate utilized to discount estimated future cash flows, the lower the fair value measurement. Additionally, fair value estimates include assumptions about prepayment speeds which ranged from 9% - 29% or a weighted average prepayment speed of 12.93% used as an input to value the pool of mortgage servicing rights at September 30, 2015 . Prepayment speeds are inversely related to the fair value of mortgage servicing rights as an increase in prepayment speeds results in a decreased valuation. Derivative instruments —The Company’s derivative instruments include interest rate swaps and caps, 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 and caps are valued by a third party, using models that primarily use market observable inputs, such as yield curves, and are corroborated 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. 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, Policy	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. The following methods and assumptions were used by the Company in estimating fair values of financial instruments that were not previously disclosed. Loans. 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. The primary impact of credit risk on the present value of the loan portfolio, however, was assessed through the use of the allowance for loan losses, which is believed to represent the current fair value of probable incurred losses for purposes of the fair value calculation. 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. Federal Home Loan Bank advances. The fair value of Federal Home Loan Bank advances is obtained from the Federal Home Loan Bank 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 Federal Home Loan Bank 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. 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.
Foreclosed Assets, Policy	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.
Stock-Based Compensation, Policy	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. Expected life of 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
Share-based Compensation, Option and Incentive Plans, Policy	Stock based compensation is recognized based upon the number of awards that are ultimately expected to vest, taking into account expected forfeitures. In addition, for performance-based awards, an estimate is made of the number of shares expected to vest as a result of projected performance against the performance criteria in the award to determine the amount of compensation expense to recognize. The estimate is reevaluated periodically and total compensation expense is adjusted for any change in estimate in the current period. Stock-based compensation expense recognized in the Consolidated Statements of Income was $2.5 million in the third quarter of 2015 and $2.2 million in the third quarter of 2014, and $7.8 million and $8.1 million for the year-to-date periods, respectively.
Earnings Per Share, Policy	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 Employee Stock Purchase Plan and the Directors Deferred Fee and Stock 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 (Tables)

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
Summary of FDIC Indemnification Asset	The following table summarizes the activity in the Company’s FDIC indemnification (liability) asset during the periods indicated: Three Months Ended Nine Months Ended (Dollars in thousands) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Balance at beginning of period $ 3,429 $ 46,115 $ 11,846 $ 85,672 Additions from acquisitions — — — — Additions from reimbursable expenses 1,039 1,584 3,548 4,933 Amortization (718 ) (1,382 ) (3,184 ) (4,441 ) Changes in expected reimbursements from the FDIC for changes in expected credit losses (5,236 ) (12,124 ) (13,546 ) (41,153 ) Payments received from the FDIC (1,547 ) (6,834 ) (1,697 ) (17,652 ) Balance at end of period $ (3,033 ) $ 27,359 $ (3,033 ) $ 27,359

Available-For-Sale Securities (

Available-For-Sale Securities (Tables)	9 Months Ended
	Sep. 30, 2015
Available-for-sale Securities [Abstract]
Schedule of the Available-for-Sale Securities Reconciliation	The following tables are a summary of the available-for-sale securities portfolio as of the dates shown: September 30, 2015 (Dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury $ 288,185 $ 101 $ (2,364 ) $ 285,922 U.S. Government agencies 657,297 2,726 (15,000 ) 645,023 Municipal 294,073 5,354 (2,085 ) 297,342 Corporate notes: Financial issuers 114,976 1,656 (1,216 ) 115,416 Other 1,525 6 (2 ) 1,529 Mortgage-backed: (1) Mortgage-backed securities 778,240 4,974 (10,913 ) 772,301 Collateralized mortgage obligations 42,724 343 (323 ) 42,744 Equity securities 49,356 4,993 (345 ) 54,004 Total available-for-sale securities $ 2,226,376 $ 20,153 $ (32,248 ) $ 2,214,281 December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (Dollars in thousands) U.S. Treasury $ 388,713 $ 84 $ (6,992 ) $ 381,805 U.S. Government agencies 686,106 4,113 (21,903 ) 668,316 Municipal 234,951 5,318 (1,740 ) 238,529 Corporate notes: Financial issuers 129,309 2,006 (1,557 ) 129,758 Other 3,766 55 — 3,821 Mortgage-backed: (1) Mortgage-backed securities 271,129 5,448 (4,928 ) 271,649 Collateralized mortgage obligations 47,347 249 (535 ) 47,061 Equity securities 46,592 4,872 (325 ) 51,139 Total available-for-sale securities $ 1,807,913 $ 22,145 $ (37,980 ) $ 1,792,078 September 30, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (Dollars in thousands) U.S. Treasury $ 388,873 $ 372 $ (10,984 ) $ 378,261 U.S. Government agencies 771,255 3,866 (35,369 ) 739,752 Municipal 184,015 4,969 (1,881 ) 187,103 Corporate notes: Financial issuers 129,259 2,252 (1,208 ) 130,303 Other 3,773 79 — 3,852 Mortgage-backed: (1) Mortgage-backed securities 246,354 4,303 (8,938 ) 241,719 Collateralized mortgage obligations 49,909 357 (763 ) 49,503 Equity securities 47,595 4,958 (398 ) 52,155 Total available-for-sale securities $ 1,821,033 $ 21,156 $ (59,541 ) $ 1,782,648 (1) Consisting entirely of residential mortgage-backed securities, none of which are subprime.
Available-for-Sale Securities, Continuous Unrealized Loss Position, Fair Value	The following table presents the portion of the Company’s available-for-sale securities portfolio which has gross unrealized losses, reflecting the length of time that individual securities have been in a continuous unrealized loss position at September 30, 2015 : 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 U.S. Treasury $ 202,795 $ (2,364 ) $ — $ — $ 202,795 $ (2,364 ) U.S. Government agencies 218,297 (4,932 ) 251,654 (10,068 ) 469,951 (15,000 ) Municipal 68,140 (964 ) 37,002 (1,121 ) 105,142 (2,085 ) Corporate notes: Financial issuers 23,052 (152 ) 44,894 (1,064 ) 67,946 (1,216 ) Other 999 (2 ) — — 999 (2 ) Mortgage-backed: Mortgage-backed securities 519,631 (7,011 ) 120,261 (3,902 ) 639,892 (10,913 ) Collateralized mortgage obligations 7,167 (63 ) 9,620 (260 ) 16,787 (323 ) Equity securities 2,957 (12 ) 8,557 (333 ) 11,514 (345 ) Total $ 1,043,038 $ (15,500 ) $ 471,988 $ (16,748 ) $ 1,515,026 $ (32,248 )
Schedule of Realized Gain (Loss)	The following table provides information as to the amount of gross gains and gross losses realized and proceeds received through the sales of available-for-sale investment securities: Three months ended September 30, Nine months ended September 30, (Dollars in thousands) 2015 2014 2015 2014 Realized gains $ 87 $ 179 $ 654 $ 333 Realized losses (185 ) (332 ) (252 ) (855 ) Net realized (losses) gains $ (98 ) $ (153 ) $ 402 $ (522 ) Other than temporary impairment charges — — — — (Losses) gains on available-for-sale securities, net $ (98 ) $ (153 ) $ 402 $ (522 ) Proceeds from sales of available-for-sale securities $ 82,827 $ 382,552 $ 1,216,860 $ 578,594
Investments Classified by Contractual Maturity Date	The amortized cost and fair value of securities as of September 30, 2015 , December 31, 2014 and September 30, 2014 , 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: September 30, 2015 December 31, 2014 September 30, 2014 (Dollars in thousands) Amortized Cost Fair Value Amortized Cost Fair Value Amortized Cost Fair Value Due in one year or less $ 164,374 $ 164,429 $ 285,596 $ 285,889 $ 216,244 $ 216,582 Due in one to five years 186,199 186,592 172,647 172,885 309,914 310,917 Due in five to ten years 343,468 342,271 331,389 325,644 327,505 317,654 Due after ten years 662,015 651,940 653,213 637,811 623,512 594,118 Mortgage-backed 820,964 815,045 318,476 318,710 296,263 291,222 Equity securities 49,356 54,004 46,592 51,139 47,595 52,155 Total available-for-sale securities $ 2,226,376 $ 2,214,281 $ 1,807,913 $ 1,792,078 $ 1,821,033 $ 1,782,648

Loans (Tables)

Loans (Tables)	9 Months Ended
	Sep. 30, 2015
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: September 30, December 31, September 30, (Dollars in thousands) 2015 2014 2014 Balance: Commercial $ 4,400,185 $ 3,924,394 $ 3,689,671 Commercial real estate 5,307,566 4,505,753 4,510,375 Home equity 797,465 716,293 720,058 Residential real estate 571,743 483,542 470,319 Premium finance receivables—commercial 2,407,075 2,350,833 2,377,892 Premium finance receivables—life insurance 2,700,275 2,277,571 2,134,405 Consumer and other 131,902 151,012 149,339 Total loans, net of unearned income, excluding covered loans $ 16,316,211 $ 14,409,398 $ 14,052,059 Covered loans 168,609 226,709 254,605 Total loans $ 16,484,820 $ 14,636,107 $ 14,306,664 Mix: Commercial 27 % 26 % 26 % Commercial real estate 32 31 31 Home equity 5 5 5 Residential real estate 3 3 3 Premium finance receivables—commercial 15 16 17 Premium finance receivables—life insurance 16 16 15 Consumer and other 1 1 1 Total loans, net of unearned income, excluding covered loans 99 % 98 % 98 % Covered loans 1 2 2 Total loans 100 % 100 % 100 %
Schedule of Unpaid Principal Balance and Carrying Value of Acquired Loans	The following table presents the unpaid principal balance and carrying value for these acquired loans: September 30, 2015 December 31, 2014 Unpaid Principal Carrying Unpaid Principal Carrying (Dollars in thousands) Balance Value Balance Value Bank acquisitions $ 356,615 $ 295,801 $ 285,809 $ 227,229 Life insurance premium finance loans acquisition 378,040 373,586 399,665 393,479
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period	The following table provides estimated details as of the date of acquisition on loans acquired in 2015 with evidence of credit quality deterioration since origination: (Dollars in thousands) North Bank CBWGE Suburban Delavan Contractually required payments including interest $ 8,563 $ 38,656 $ 95,804 $ 15,791 Less: Nonaccretable difference 1,027 4,437 13,888 1,442 Cash flows expected to be collected (1) 7,536 34,219 81,916 14,349 Less: Accretable yield 866 2,895 5,334 898 Fair value of PCI loans acquired 6,670 31,324 76,582 13,451 (1) Represents undiscounted expected principal and interest cash at acquisition.
Activity Related to Accretable Yield of Loans Acquired With Evidence of Credit Quality Deterioratio Since Origination	The following table provides activity for the accretable yield of PCI loans: Three Months Ended Nine Months Ended (Dollars in thousands) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Accretable yield, beginning balance $ 63,643 $ 97,281 $ 79,102 $ 115,909 Acquisitions 9,095 — 9,993 — Accretable yield amortized to interest income (5,939 ) (7,847 ) (18,359 ) (28,438 ) Accretable yield amortized to indemnification asset (1) (3,280 ) (8,784 ) (10,945 ) (25,593 ) Reclassification from non-accretable difference (2) 2,298 2,584 5,154 29,092 Increases (decreases) in interest cash flows due to payments and changes in interest rates (610 ) 4,675 262 (3,061 ) Accretable yield, ending balance (3) $ 65,207 $ 87,909 $ 65,207 $ 87,909 (1) Represents the portion of the current period accreted yield, resulting from lower expected losses, applied to reduce the loss share indemnification asset. (2) Reclassification is the result of subsequent increases in expected principal cash flows. (3) As of September 30, 2015, the Company estimates that the remaining accretable yield balance to be amortized to the indemnification asset for the bank acquisitions is $10.0 million . The remainder of the accretable yield related to bank acquisitions is expected to be amortized to interest income.

Allowance for Loan Losses, Al28

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 (Tables)	9 Months Ended
	Sep. 30, 2015
Loans and Leases Receivable, Allowance [Abstract]
Schedule of Aging of the Company's Loan Portfolio	The tables below show the aging of the Company’s loan portfolio at September 30, 2015 , December 31, 2014 and September 30, 2014 : As of September 30, 2015 90+ days and still accruing 60-89 days past due 30-59 days past due (Dollars in thousands) Nonaccrual Current Total Loans Loan Balances: Commercial Commercial and industrial $ 12,006 $ — $ 2,731 $ 9,331 $ 2,622,207 $ 2,646,275 Franchise — — 80 376 221,545 222,001 Mortgage warehouse lines of credit — — — — 136,614 136,614 Community Advantage—homeowners association — — 44 — 123,165 123,209 Aircraft — — — 378 5,993 6,371 Asset-based lending 12 — 1,313 247 800,798 802,370 Tax exempt — — — — 232,667 232,667 Leases — — — 89 205,697 205,786 Other — — — — 1,953 1,953 PCI - commercial (1) — 217 — 39 22,683 22,939 Total commercial 12,018 217 4,168 10,460 4,373,322 4,400,185 Commercial real estate: Residential construction — — — 1,141 60,130 61,271 Commercial construction 31 — — 2,394 283,538 285,963 Land 1,756 — — 2,207 75,113 79,076 Office 4,045 — 10,861 2,362 773,043 790,311 Industrial 11,637 — 786 897 622,804 636,124 Retail 2,022 — 1,536 821 781,463 785,842 Multi-family 1,525 — 512 744 684,878 687,659 Mixed use and other 7,601 — 2,340 12,871 1,797,516 1,820,328 PCI - commercial real estate (1) — 13,547 299 583 146,563 160,992 Total commercial real estate 28,617 13,547 16,334 24,020 5,225,048 5,307,566 Home equity 8,365 — 811 4,124 784,165 797,465 Residential real estate 14,557 — 1,017 1,195 551,292 568,061 PCI - residential real estate (1) — 424 323 411 2,524 3,682 Premium finance receivables Commercial insurance loans 13,751 8,231 6,664 13,659 2,364,770 2,407,075 Life insurance loans — — 9,656 2,627 2,314,406 2,326,689 PCI - life insurance loans (1) — — — — 373,586 373,586 Consumer and other 297 140 56 935 130,474 131,902 Total loans, net of unearned income, excluding covered loans $ 77,605 $ 22,559 $ 39,029 $ 57,431 $ 16,119,587 $ 16,316,211 Covered loans 6,540 7,626 1,392 802 152,249 168,609 Total loans, net of unearned income $ 84,145 $ 30,185 $ 40,421 $ 58,233 $ 16,271,836 $ 16,484,820 (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. As of December 31, 2014 90+ days and still accruing 60-89 days past due 30-59 days past due (Dollars in thousands) Nonaccrual Current Total Loans Loan Balances: Commercial Commercial and industrial $ 9,132 $ 474 $ 3,161 $ 7,492 $ 2,213,105 $ 2,233,364 Franchise — — 308 1,219 231,789 233,316 Mortgage warehouse lines of credit — — — — 139,003 139,003 Community Advantage—homeowners association — — — — 106,364 106,364 Aircraft — — — — 8,065 8,065 Asset-based lending 25 — 1,375 2,394 802,608 806,402 Tax exempt — — — — 217,487 217,487 Leases — — 77 315 159,744 160,136 Other — — — — 11,034 11,034 PCI - commercial (1) — 365 202 138 8,518 9,223 Total commercial 9,157 839 5,123 11,558 3,897,717 3,924,394 Commercial real estate Residential construction — — 250 76 38,370 38,696 Commercial construction 230 — — 2,023 185,513 187,766 Land 2,656 — — 2,395 86,779 91,830 Office 7,288 — 2,621 1,374 694,149 705,432 Industrial 2,392 — — 3,758 617,820 623,970 Retail 4,152 — 116 3,301 723,919 731,488 Multi-family 249 — 249 1,921 603,323 605,742 Mixed use and other 9,638 — 2,603 9,023 1,443,853 1,465,117 PCI - commercial real estate (1) — 10,976 6,393 4,016 34,327 55,712 Total commercial real estate 26,605 10,976 12,232 27,887 4,428,053 4,505,753 Home equity 6,174 — 983 3,513 705,623 716,293 Residential real estate 15,502 — 267 6,315 459,224 481,308 PCI - residential real estate (1) — 549 — — 1,685 2,234 Premium finance receivables Commercial insurance loans 12,705 7,665 5,995 17,328 2,307,140 2,350,833 Life insurance loans — — 13,084 339 1,870,669 1,884,092 PCI - life insurance loans (1) — — — — 393,479 393,479 Consumer and other 277 119 293 838 149,485 151,012 Total loans, net of unearned income, excluding covered loans $ 70,420 $ 20,148 $ 37,977 $ 67,778 $ 14,213,075 $ 14,409,398 Covered loans 7,290 17,839 1,304 4,835 195,441 226,709 Total loans, net of unearned income $ 77,710 $ 37,987 $ 39,281 $ 72,613 $ 14,408,516 $ 14,636,107 (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. As of September 30, 2014 90+ days and still accruing 60-89 days past due 30-59 days past due (Dollars in thousands) Nonaccrual Current Total Loans Loan Balances: Commercial Commercial and industrial $ 10,430 $ — $ 7,333 $ 8,559 $ 2,044,505 $ 2,070,827 Franchise — — — 1,221 237,079 238,300 Mortgage warehouse lines of credit — — — — 121,585 121,585 Community Advantage—homeowners association — — — — 99,595 99,595 Aircraft — — — — 6,146 6,146 Asset-based lending 25 — 2,959 1,220 777,723 781,927 Tax exempt — — — — 205,150 205,150 Leases — — — — 145,439 145,439 Other — — — — 11,403 11,403 PCI - commercial (1) — 863 64 137 8,235 9,299 Total commercial 10,455 863 10,356 11,137 3,656,860 3,689,671 Commercial real estate: Residential construction — — — — 30,237 30,237 Commercial construction 425 — — — 159,383 159,808 Land 2,556 — 1,316 2,918 94,449 101,239 Office 7,366 — 1,696 1,888 688,390 699,340 Industrial 2,626 — 224 367 624,669 627,886 Retail 6,205 — — 4,117 715,568 725,890 Multi-family 249 — 793 2,319 674,610 677,971 Mixed use and other 7,936 — 1,468 10,323 1,407,659 1,427,386 PCI - commercial real estate (1) — 14,294 — 5,807 40,517 60,618 Total commercial real estate 27,363 14,294 5,497 27,739 4,435,482 4,510,375 Home equity 5,696 — 1,181 2,597 710,584 720,058 Residential real estate 15,730 — 670 2,696 448,528 467,624 PCI - residential real estate (1) — 930 30 — 1,735 2,695 Premium finance receivables Commercial insurance loans 14,110 7,115 6,279 14,157 2,336,231 2,377,892 Life insurance loans — — 7,533 6,942 1,712,328 1,726,803 PCI - life insurance loans (1) — — — — 407,602 407,602 Consumer and other 426 175 123 1,133 147,482 149,339 Total loans, net of unearned income, excluding covered loans $ 73,780 $ 23,377 $ 31,669 $ 66,401 $ 13,856,832 $ 14,052,059 Covered loans 6,042 26,170 4,289 5,655 212,449 254,605 Total loans, net of unearned income $ 79,822 $ 49,547 $ 35,958 $ 72,056 $ 14,069,281 $ 14,306,664 (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.
Summary of Performance by Loan Class	The following table presents the recorded investment based on performance of loans by class, excluding covered loans, per the most recent analysis at September 30, 2015 , December 31, 2014 and September 30, 2014 : Performing Non-performing Total (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 September 30, December 31, 2014 September 30, September 30, December 31, 2014 September 30, Loan Balances: Commercial Commercial and industrial $ 2,634,269 $ 2,223,758 $ 2,060,397 $ 12,006 $ 9,606 $ 10,430 $ 2,646,275 $ 2,233,364 $ 2,070,827 Franchise 222,001 233,316 238,300 — — — 222,001 233,316 238,300 Mortgage warehouse lines of credit 136,614 139,003 121,585 — — — 136,614 139,003 121,585 Community Advantage—homeowners association 123,209 106,364 99,595 — — — 123,209 106,364 99,595 Aircraft 6,371 8,065 6,146 — — — 6,371 8,065 6,146 Asset-based lending 802,358 806,377 781,902 12 25 25 802,370 806,402 781,927 Tax exempt 232,667 217,487 205,150 — — — 232,667 217,487 205,150 Leases 205,786 160,136 145,439 — — — 205,786 160,136 145,439 Other 1,953 11,034 11,403 — — — 1,953 11,034 11,403 PCI - commercial (1) 22,939 9,223 9,299 — — — 22,939 9,223 9,299 Total commercial 4,388,167 3,914,763 3,679,216 12,018 9,631 10,455 4,400,185 3,924,394 3,689,671 Commercial real estate Residential construction 61,271 38,696 30,237 — — — 61,271 38,696 30,237 Commercial construction 285,932 187,536 159,383 31 230 425 285,963 187,766 159,808 Land 77,320 89,174 98,683 1,756 2,656 2,556 79,076 91,830 101,239 Office 786,266 698,144 691,974 4,045 7,288 7,366 790,311 705,432 699,340 Industrial 624,487 621,578 625,260 11,637 2,392 2,626 636,124 623,970 627,886 Retail 783,820 727,336 719,685 2,022 4,152 6,205 785,842 731,488 725,890 Multi-family 686,134 605,493 677,722 1,525 249 249 687,659 605,742 677,971 Mixed use and other 1,812,727 1,455,479 1,419,450 7,601 9,638 7,936 1,820,328 1,465,117 1,427,386 PCI - commercial real estate (1) 160,992 55,712 60,618 — — — 160,992 55,712 60,618 Total commercial real estate 5,278,949 4,479,148 4,483,012 28,617 26,605 27,363 5,307,566 4,505,753 4,510,375 Home equity 789,100 710,119 714,362 8,365 6,174 5,696 797,465 716,293 720,058 Residential real estate 553,504 465,806 451,894 14,557 15,502 15,730 568,061 481,308 467,624 PCI - residential real estate (1) 3,682 2,234 2,695 — — — 3,682 2,234 2,695 Premium finance receivables Commercial insurance loans 2,385,093 2,330,463 2,356,667 21,982 20,370 21,225 2,407,075 2,350,833 2,377,892 Life insurance loans 2,326,689 1,884,092 1,726,803 — — — 2,326,689 1,884,092 1,726,803 PCI - life insurance loans (1) 373,586 393,479 407,602 — — — 373,586 393,479 407,602 Consumer and other 131,465 150,617 148,738 437 395 601 131,902 151,012 149,339 Total loans, net of unearned income, excluding covered loans $ 16,230,235 $ 14,330,721 $ 13,970,989 $ 85,976 $ 78,677 $ 81,070 $ 16,316,211 $ 14,409,398 $ 14,052,059 (1) PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 6 - Loans for further discussion of these purchased loans.
Summary of Activity in the Allowance for Credit Losses	A summary of activity in the allowance for credit losses by loan portfolio (excluding covered loans) for the three months ended September 30, 2015 and 2014 is as follows: Three months ended September 30, 2015 Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Commercial Allowance for credit losses Allowance for loan losses at beginning of period $ 32,900 $ 42,198 $ 12,288 $ 5,019 $ 6,921 $ 878 $ 100,204 Other adjustments (12 ) (85 ) — (6 ) (50 ) — (153 ) Reclassification from allowance for unfunded lending-related commitments — (42 ) — — — — (42 ) Charge-offs (964 ) (1,948 ) (1,116 ) (1,138 ) (1,595 ) (116 ) (6,877 ) Recoveries 462 213 42 136 294 52 1,199 Provision for credit losses 1,604 3,725 1,009 575 1,511 241 8,665 Allowance for loan losses at period end $ 33,990 $ 44,061 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 102,996 Allowance for unfunded lending-related commitments at period end $ — $ 926 $ — $ — $ — $ — $ 926 Allowance for credit losses at period end $ 33,990 $ 44,987 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 103,922 Individually evaluated for impairment $ 1,881 $ 5,832 $ 239 $ 544 $ — $ 30 $ 8,526 Collectively evaluated for impairment 31,943 38,361 11,984 4,042 7,081 1,024 94,435 Loans acquired with deteriorated credit quality 166 794 — — — 1 961 Loans at period end Individually evaluated for impairment $ 18,211 $ 68,947 $ 8,365 $ 18,267 $ — $ 430 $ 114,220 Collectively evaluated for impairment 4,359,035 5,077,627 789,100 549,794 4,733,764 131,472 15,640,792 Loans acquired with deteriorated credit quality 22,939 160,992 — 3,682 373,586 — 561,199 Three months ended September 30, 2014 Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Allowance for credit losses Allowance for loan losses at beginning of period $ 26,038 $ 40,702 $ 13,918 $ 3,733 $ 6,309 $ 1,553 $ 92,253 Other adjustments (32 ) (265 ) (1 ) (2 ) (35 ) — (335 ) Reclassification from allowance for unfunded lending-related commitments — 62 — — — — 62 Charge-offs (832 ) (4,510 ) (748 ) (205 ) (1,557 ) (250 ) (8,102 ) Recoveries 296 275 99 111 290 42 1,113 Provision for credit losses 2,442 2,395 (308 ) 405 1,260 (166 ) 6,028 Allowance for loan losses at period end $ 27,912 $ 38,659 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,019 Allowance for unfunded lending-related commitments at period end $ — $ 822 $ — $ — $ — $ — $ 822 Allowance for credit losses at period end $ 27,912 $ 39,481 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,841 Individually evaluated for impairment $ 2,296 $ 3,507 $ 292 $ 512 $ — $ 53 $ 6,660 Collectively evaluated for impairment 25,427 35,967 12,668 3,530 6,267 1,103 84,962 Loans acquired with deteriorated credit quality 189 7 — — — 23 219 Loans at period end Individually evaluated for impairment $ 16,568 $ 89,201 $ 5,922 $ 18,383 $ — $ 870 $ 130,944 Collectively evaluated for impairment 3,663,804 4,360,556 714,136 449,241 4,104,695 148,469 13,440,901 Loans acquired with deteriorated credit quality 9,299 60,618 — 2,695 407,602 — 480,214 Nine months ended September 30, 2015 Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Commercial Allowance for credit losses Allowance for loan losses at beginning of period $ 31,699 $ 35,533 $ 12,500 $ 4,218 $ 6,513 $ 1,242 $ 91,705 Other adjustments (42 ) (346 ) — (14 ) (92 ) — (494 ) Reclassification from allowance for unfunded lending-related commitments — (151 ) — — — — (151 ) Charge-offs (2,884 ) (3,809 ) (3,547 ) (2,692 ) (4,384 ) (342 ) (17,658 ) Recoveries 1,117 2,349 129 228 1,081 139 5,043 Provision for credit losses 4,100 10,485 3,141 2,846 3,963 16 24,551 Allowance for loan losses at period end $ 33,990 $ 44,061 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 102,996 Allowance for unfunded lending-related commitments at period end $ — $ 926 $ — $ — $ — $ — $ 926 Allowance for credit losses at period end $ 33,990 $ 44,987 $ 12,223 $ 4,586 $ 7,081 $ 1,055 $ 103,922 Nine months ended September 30, 2014 Commercial Commercial Real Estate Home Equity Residential Real Estate Premium Finance Receivable Consumer and Other Total, Excluding Covered Loans (Dollars in thousands) Allowance for credit losses Allowance for loan losses at beginning of period $ 23,092 $ 48,658 $ 12,611 $ 5,108 $ 5,583 $ 1,870 $ 96,922 Other adjustments (69 ) (482 ) (3 ) (6 ) (28 ) — (588 ) Reclassification from allowance for unfunded lending-related commitments — (102 ) — — — — (102 ) Charge-offs (3,864 ) (11,354 ) (3,745 ) (1,120 ) (4,259 ) (636 ) (24,978 ) Recoveries 883 762 478 316 925 256 3,620 Provision for credit losses 7,870 1,177 3,619 (256 ) 4,046 (311 ) 16,145 Allowance for loan losses at period end $ 27,912 $ 38,659 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,019 Allowance for unfunded lending-related commitments at period end $ — $ 822 $ — $ — $ — $ — $ 822 Allowance for credit losses at period end $ 27,912 $ 39,481 $ 12,960 $ 4,042 $ 6,267 $ 1,179 $ 91,841
Summary of Activity in the Allowance for Covered Loan Losses	A summary of activity in the allowance for covered loan losses for the three months ended September 30, 2015 and 2014 is as follows: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, (Dollars in thousands) 2015 2014 2015 2014 Balance at beginning of period $ 2,215 $ 1,667 $ 2,131 $ 10,092 Provision for covered loan losses before benefit attributable to FDIC loss share agreements (1,716 ) (818 ) (3,339 ) (8,703 ) Benefit attributable to FDIC loss share agreements 1,373 654 2,671 6,962 Net provision for covered loan losses (343 ) (164 ) (668 ) (1,741 ) Decrease in FDIC indemnification asset (1,373 ) (654 ) (2,671 ) (6,962 ) Loans charged-off (287 ) (293 ) (664 ) (5,346 ) Recoveries of loans charged-off 2,706 2,099 4,790 6,612 Net recoveries (charge-offs) 2,419 1,806 4,126 1,266 Balance at end of period $ 2,918 $ 2,655 $ 2,918 $ 2,655
Summary of Impaired Loans, Including Restructured Loans	A summary of impaired loans, including troubled debt restructurings ("TDRs"), is as follows: September 30, December 31, September 30, (Dollars in thousands) 2015 2014 2014 Impaired loans (included in non-performing and TDRs): Impaired loans with an allowance for loan loss required (1) $ 51,113 $ 69,487 $ 68,471 Impaired loans with no allowance for loan loss required 61,914 57,925 61,066 Total impaired loans (2) $ 113,027 $ 127,412 $ 129,537 Allowance for loan losses related to impaired loans $ 8,483 $ 6,270 $ 6,577 TDRs $ 59,320 $ 82,275 $ 83,385 (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 by Loan Class	The following tables present impaired loans evaluated for impairment by loan class for the periods ended as follows: For the Nine Months Ended As of September 30, 2015 September 30, 2015 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (Dollars in thousands) Impaired loans with a related ASC 310 allowance recorded Commercial Commercial and industrial $ 8,580 $ 9,118 $ 1,865 $ 8,906 $ 381 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending — — — — — Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction — — — — — Land 3,559 7,309 31 3,713 362 Office 6,765 7,724 2,162 7,113 263 Industrial 10,049 10,542 1,550 10,662 421 Retail 8,899 9,596 381 8,906 306 Multi-family 1,199 1,622 203 1,210 60 Mixed use and other 7,162 7,345 1,501 7,250 224 Home equity 547 762 239 672 25 Residential real estate 4,225 4,326 521 4,280 130 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — PCI - life insurance — — — — — Consumer and other 128 128 30 139 6 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial and industrial $ 9,142 $ 11,997 $ — $ 9,716 $ 539 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending 12 1,573 — 4 66 Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction 2,023 2,023 — 2,023 73 Commercial construction 31 32 — 11 — Land 4,114 4,874 — 4,232 130 Office 4,171 5,120 — 4,243 194 Industrial 2,255 2,448 — 2,304 141 Retail 3,140 3,302 — 3,305 104 Multi-family 1,330 1,635 — 1,522 50 Mixed use and other 13,788 16,576 — 14,668 563 Home equity 7,818 8,406 — 7,065 229 Residential real estate 13,788 15,932 — 14,387 449 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — PCI - life insurance — — — — — Consumer and other 302 398 — 311 15 Total loans, net of unearned income, excluding covered loans $ 113,027 $ 132,788 $ 8,483 $ 116,642 $ 4,731 For the Twelve Months Ended As of December 31, 2014 December 31, 2014 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (Dollars in thousands) Impaired loans with a related ASC 310 allowance recorded Commercial Commercial and industrial $ 9,989 $ 10,785 $ 1,915 $ 10,784 $ 539 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending — — — — — Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction — — — — — Land 5,011 8,626 43 5,933 544 Office 11,038 12,863 305 11,567 576 Industrial 195 277 15 214 13 Retail 11,045 14,566 487 12,116 606 Multi-family 2,808 3,321 158 2,839 145 Mixed use and other 21,777 24,076 2,240 21,483 1,017 Home equity 1,946 2,055 475 1,995 80 Residential real estate 5,467 5,600 606 5,399 241 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 211 213 26 214 10 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial and industrial $ 5,797 $ 8,862 $ — $ 6,664 $ 595 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending 25 1,952 — 87 100 Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction 2,875 3,085 — 3,183 151 Land 10,210 10,941 — 10,268 430 Office 4,132 5,020 — 4,445 216 Industrial 4,160 4,498 — 3,807 286 Retail 5,487 7,470 — 6,915 330 Multi-family — — — — — Mixed use and other 7,985 8,804 — 9,533 449 Home equity 4,453 6,172 — 4,666 256 Residential real estate 12,640 14,334 — 12,682 595 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 161 222 — 173 11 Total loans, net of unearned income, excluding covered loans $ 127,412 $ 153,742 $ 6,270 $ 134,967 $ 7,190 For the Nine Months Ended As of September 30, 2014 September 30, 2014 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (Dollars in thousands) Impaired loans with a related ASC 310 allowance recorded Commercial Commercial and industrial $ 8,384 $ 11,333 $ 2,273 $ 9,367 $ 537 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending — — — — — Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction 425 440 195 432 15 Land 7,502 7,502 40 7,572 193 Office 8,198 9,671 322 8,493 300 Industrial 2,567 2,672 151 2,595 92 Retail 10,861 11,279 921 10,826 362 Multi-family 2,822 3,335 107 2,847 109 Mixed use and other 21,172 21,453 1,738 20,891 656 Home equity 1,438 1,533 292 1,491 42 Residential real estate 4,889 4,986 485 4,783 157 Premium finance receivables — Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 213 215 53 215 6 Impaired loans with no related ASC 310 allowance recorded Commercial Commercial and industrial $ 7,563 $ 8,285 $ — $ 7,909 $ 306 Franchise — — — — — Mortgage warehouse lines of credit — — — — — Community Advantage—homeowners association — — — — — Aircraft — — — — — Asset-based lending 25 1,952 — 108 75 Tax exempt — — — — — Leases — — — — — Other — — — — — Commercial real estate Residential construction — — — — — Commercial construction 2,803 2,803 — 2,777 98 Land 8,101 12,432 — 8,969 538 Office 5,159 6,359 — 6,679 244 Industrial 1,903 2,110 — 1,962 76 Retail 8,095 10,177 — 8,647 342 Multi-family — — — — — Mixed use and other 9,042 11,772 — 9,467 445 Home equity 4,484 6,490 — 4,806 207 Residential real estate 13,234 14,953 — 13,291 496 Premium finance receivables Commercial insurance — — — — — Life insurance — — — — — Purchased life insurance — — — — — Consumer and other 657 721 — 665 29 Total loans, net of unearned income, excluding covered loans $ 129,537 $ 152,473 $ 6,577 $ 134,792 $ 5,325
Summary of the Post-Modification Balance of TDRs	The tables below present a summary of the post-modification balance of loans restructured during the three and nine months ended September 30, 2015 and 2014, respectively, which represent TDRs: Three months ended September 30, 2015 (Dollars in thousands) Total (1)(2) Extension at Below Market (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial and industrial — $ — — $ — — $ — — $ — — $ — Commercial real estate Office — — — — — — — — — — Industrial — — — — — — — — — — Retail — — — — — — — — — — Multi-family — — — — — — — — — — Mixed use and other — — — — — — — — — — Residential real estate and other 1 222 1 222 1 222 — — — — Total loans 1 $ 222 1 $ 222 1 $ 222 — $ — — $ — Three months ended September 30, 2014 (Dollars in thousands) Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial and industrial — $ — — $ — — $ — — $ — — $ — Commercial real estate Office — — — — — — — — — — Industrial — — — — — — — — — — Retail — — — — — — — — — — Multi-family — — — — — — — — — — Mixed use and other — — — — — — — — — — Residential real estate and other 3 667 2 456 3 667 — — — — Total loans 3 $ 667 2 $ 456 3 $ 667 — $ — — $ — (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. Nine months ended September 30, 2015 (Dollars in thousands) Total (1)(2) Extension at Below Market (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial and industrial — $ — — $ — — $ — — $ — — $ — Commercial real estate Office — — — — — — — — — — Industrial 1 169 1 169 — — 1 169 — — Retail — — — — — — — — — — Multi-family — — — — — — — — — — Mixed use and other — — — — — — — — — — Residential real estate and other 9 1,664 9 1,664 5 674 1 50 — — Total loans 10 $ 1,833 10 $ 1,833 5 $ 674 2 $ 219 — $ — Nine months ended September 30, 2014 (Dollars in thousands) Total (1)(2) Extension at Below Market Terms (2) Reduction of Interest Rate (2) Modification to Interest-only Payments (2) Forgiveness of Debt (2) Count Balance Count Balance Count Balance Count Balance Count Balance Commercial Commercial and industrial 1 $ 88 1 $ 88 — $ — 1 $ 88 — $ — Commercial real estate Office 1 790 1 790 — — — — — — Industrial 1 1,078 1 1,078 — — 1 1,078 — — Retail 1 202 1 202 — — — — — — Multi-family 1 181 — — 1 181 — — — — Mixed use and other 7 4,926 3 2,837 7 4,926 1 1,273 — — Residential real estate and other 4 887 3 676 3 667 1 220 — — Total loans 16 $ 8,152 10 $ 5,671 11 $ 5,774 4 $ 2,659 — $ — (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.
Summary of TDRs Subsequent Default Under the Restructured Terms	The following table presents a summary of all loans restructured in TDRs during the twelve months ended September 30, 2015 and 2014, and such loans which were in payment default under the restructured terms during the respective periods below: (Dollars in thousands) As of September 30, 2015 Three Months Ended September 30, 2015 Nine Months Ended September 30, 2015 Total (1)(3) Payments in Default (2)(3) Payments in Default (2)(3) Count Balance Count Balance Count Balance Commercial Commercial and industrial 1 $ 1,461 — $ — — $ — Commercial real estate Land — — — — — — Office 1 720 — — — — Industrial 2 854 1 685 1 685 Retail — — — — — — Multi-family — — — — — — Mixed use and other — — — — — — Residential real estate and other 11 2,613 2 131 3 345 Total loans 15 $ 5,648 3 $ 816 4 $ 1,030 (1) Total TDRs represent all loans restructured in TDRs during the previous twelve months from the date 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. (Dollars in thousands) As of September 30, 2014 Three Months Ended September 30, 2014 Nine Months Ended September 30, 2014 Total (1)(3) Payments in Default (2)(3) Payments in Default (2)(3) Count Balance Count Balance Count Balance Commercial Commercial and industrial 1 $ 88 1 $ 88 1 $ 88 Commercial real estate Land — — — — — — Office 1 790 — — — — Industrial 1 1,078 1 1,078 1 1,078 Retail 1 202 — — — — Multi-family 1 181 — — — — Mixed use and other 10 6,341 2 482 2 482 Residential real estate and other 6 1,406 2 380 2 380 Total loans 21 $ 10,086 6 $ 2,028 6 $ 2,028 (1) Total TDRs represent all loans restructured in TDRs during the previous twelve months from the date 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.

Goodwill and Other Intangible29

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2015
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, 2015 Goodwill Acquired Impairment Loss Goodwill Adjustments September 30, 2015 Community banking $ 331,752 $ 69,398 $ — $ — $ 401,150 Specialty finance 41,768 — — (2,866 ) 38,902 Wealth management 32,114 — — — 32,114 Total $ 405,634 $ 69,398 $ — $ (2,866 ) $ 472,166
Summary of Finite-Lived Intangible Assets	A summary of finite-lived intangible assets as of the dates shown and the expected amortization as of September 30, 2015 is as follows: (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 Community banking segment: Core deposit intangibles: Gross carrying amount $ 34,840 $ 29,379 $ 40,438 Accumulated amortization (16,195 ) (17,879 ) (27,909 ) Net carrying amount $ 18,645 $ 11,500 $ 12,529 Specialty finance segment: Customer list intangibles: Gross carrying amount $ 1,800 $ 1,800 $ 1,800 Accumulated amortization (1,027 ) (941 ) (910 ) Net carrying amount $ 773 $ 859 $ 890 Wealth management segment: Customer list and other intangibles: Gross carrying amount $ 7,940 $ 7,940 $ 7,940 Accumulated amortization (1,825 ) (1,488 ) (1,375 ) Net carrying amount $ 6,115 $ 6,452 $ 6,565 Total other intangible assets, net $ 25,533 $ 18,811 $ 19,984
Estimated Amortization	Estimated amortization Actual in nine months ended September 30, 2015 $ 3,297 Estimated remaining in 2015 1,325 Estimated—2016 4,663 Estimated—2017 3,876 Estimated—2018 3,371 Estimated—2019 2,854

Deposits Deposits (Tables)

Deposits Deposits (Tables)	9 Months Ended
	Sep. 30, 2015
Deposits [Abstract]
Summary of Deposits	The following table is a summary of deposits as of the dates shown: (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 Balance: Non-interest bearing $ 4,705,994 $ 3,518,685 $ 3,253,477 NOW and interest bearing demand deposits 2,231,258 2,236,089 2,086,099 Wealth management deposits 1,469,920 1,226,916 1,212,317 Money market 4,001,518 3,651,467 3,744,682 Savings 1,684,007 1,508,877 1,465,250 Time certificates of deposit 4,135,772 4,139,810 4,303,421 Total deposits $ 18,228,469 $ 16,281,844 $ 16,065,246 Mix: Non-interest bearing 26 % 22 % 20 % NOW and interest bearing demand deposits 12 14 13 Wealth management deposits 8 8 8 Money market 22 22 23 Savings 9 9 9 Time certificates of deposit 23 25 27 Total deposits 100 % 100 % 100 %

Federal Home Loan Bank Advanc31

Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes (Tables)	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Summary of Debt	The following table is a summary of notes payable, Federal Home Loan Bank advances, other borrowings and subordinated notes as of the dates shown: (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 Federal Home Loan Bank advances $ 451,330 $ 733,050 $ 347,500 Other borrowings: Notes payable 71,250 — — Securities sold under repurchase agreements 57,590 48,566 32,530 Other 18,466 18,822 18,953 Secured borrowings 112,672 129,077 — Total other borrowings 259,978 196,465 51,483 Subordinated notes 140,000 140,000 140,000 Total Federal Home Loan Bank advances, other borrowings and subordinated notes $ 851,308 $ 1,069,515 $ 538,983
Summary of Pledged Securities Related to Securities Sold Under Repurchase Agreements	The following is a summary of these securities pledged disaggregated by investment category and maturity, and reconciled to the outstanding balance of securities sold under repurchase agreements: As of September 30, 2015 (Dollars in thousands) Overnight Sweep Collateral U.S. Treasury $ 10,003 U.S. Government agencies 2,867 Municipal 7,488 Corporate notes: Financial issuers 15,911 Mortgage-backed: Mortgage-backed securities 47,758 Total collateral pledged $ 84,027 Excess collateral 26,437 Securities sold under repurchase agreements $ 57,590

Junior Subordinated Debentures

Junior Subordinated Debentures Junior Subordinated Debentures (Tables)	9 Months Ended
	Sep. 30, 2015
Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust [Abstract]
Summary of Junior Subordinated Debentures	The following table provides a summary of the Company’s junior subordinated debentures as of September 30, 2015 . The junior subordinated debentures represent the par value of the obligations owed to the Trusts. (Dollars in thousands) Common Securities Trust Preferred Securities Junior Subordinated Debentures Rate Structure Contractual rate at 9/30/2015 Issue Date Maturity Date Earliest Redemption Date Wintrust Capital Trust III $ 774 $ 25,000 $ 25,774 L+3.25 3.54 % 04/2003 04/2033 04/2008 Wintrust Statutory Trust IV 619 20,000 20,619 L+2.80 3.13 % 12/2003 12/2033 12/2008 Wintrust Statutory Trust V 1,238 40,000 41,238 L+2.60 2.93 % 05/2004 05/2034 06/2009 Wintrust Capital Trust VII 1,550 50,000 51,550 L+1.95 2.29 % 12/2004 03/2035 03/2010 Wintrust Capital Trust VIII 1,238 40,000 41,238 L+1.45 1.78 % 08/2005 09/2035 09/2010 Wintrust Capital Trust IX 1,547 50,000 51,547 L+1.63 1.97 % 09/2006 09/2036 09/2011 Northview Capital Trust I 186 6,000 6,186 L+3.00 3.30 % 08/2003 11/2033 08/2008 Town Bankshares Capital Trust I 186 6,000 6,186 L+3.00 3.30 % 08/2003 11/2033 08/2008 First Northwest Capital Trust I 155 5,000 5,155 L+3.00 3.33 % 05/2004 05/2034 05/2009 Suburban Illinois Capital Trust II 464 15,000 15,464 L+1.75 2.09 % 12/2006 12/2036 12/2011 Community Financial Shares Statutory Trust II 109 3,500 3,609 L+1.62 1.96 % 06/2007 09/2037 06/2012 Total $ 268,566 2.48 %

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Summary of Segment Information	The following is a summary of certain operating information for reportable segments: Three months ended $ Change in Contribution % Change in Contribution (Dollars in thousands) September 30, 2015 September 30, 2014 Net interest income: Community Banking $ 132,542 $ 121,998 $ 10,544 9 % Specialty Finance 24,657 21,903 2,754 13 Wealth Management 4,368 3,877 491 13 Total Operating Segments 161,567 147,778 13,789 9 Intersegment Eliminations 3,973 3,892 81 2 Consolidated net interest income $ 165,540 $ 151,670 $ 13,870 9 % Non-interest income: Community Banking $ 45,574 $ 38,274 $ 7,300 19 % Specialty Finance 8,264 8,320 (56 ) (1 ) Wealth Management 18,362 18,191 171 1 Total Operating Segments 72,200 64,785 7,415 11 Intersegment Eliminations (7,247 ) (6,833 ) (414 ) (6 ) Consolidated non-interest income $ 64,953 $ 57,952 $ 7,001 12 % Net revenue: Community Banking $ 178,116 $ 160,272 $ 17,844 11 % Specialty Finance 32,921 30,223 2,698 9 Wealth Management 22,730 22,068 662 3 Total Operating Segments 233,767 212,563 21,204 10 Intersegment Eliminations (3,274 ) (2,941 ) (333 ) (11 ) Consolidated net revenue $ 230,493 $ 209,622 $ 20,871 10 % Segment profit: Community Banking $ 22,723 $ 26,184 $ (3,461 ) (13 )% Specialty Finance 12,545 10,973 1,572 14 Wealth Management 3,087 3,067 20 1 Consolidated net income $ 38,355 $ 40,224 $ (1,869 ) (5 )% Segment assets: Community Banking $ 18,505,830 $ 15,945,744 $ 2,560,086 16 % Specialty Finance 2,987,236 2,704,591 282,645 10 Wealth Management 550,864 519,010 31,854 6 Consolidated total assets $ 22,043,930 $ 19,169,345 $ 2,874,585 15 % Nine months ended $ Change in Contribution % Change in Contribution (Dollars in thousands) September 30, 2015 September 30, 2014 Net interest income: Community Banking $ 382,187 $ 359,981 $ 22,206 6 % Specialty Finance 67,041 60,907 6,134 10 Wealth Management 12,837 11,982 855 7 Total Operating Segments 462,065 432,870 29,195 7 Intersegment Eliminations 12,258 11,986 272 2 Consolidated net interest income $ 474,323 $ 444,856 $ 29,467 7 % Non-interest income: Community Banking $ 146,739 $ 98,930 $ 47,809 48 % Specialty Finance 25,270 24,656 614 2 Wealth Management 56,103 54,367 1,736 3 Total Operating Segments 228,112 177,953 50,159 28 Intersegment Eliminations (21,605 ) (20,370 ) (1,235 ) (6 ) Consolidated non-interest income $ 206,507 $ 157,583 $ 48,924 31 % Net revenue: Community Banking $ 528,926 $ 458,911 $ 70,015 15 % Specialty Finance 92,311 85,563 6,748 8 Wealth Management 68,940 66,349 2,591 4 Total Operating Segments 690,177 610,823 79,354 13 Intersegment Eliminations (9,347 ) (8,384 ) (963 ) (11 ) Consolidated net revenue $ 680,830 $ 602,439 $ 78,391 13 % Segment profit: Community Banking $ 76,821 $ 73,393 $ 3,428 5 % Specialty Finance 34,875 30,257 4,618 15 Wealth Management 9,542 9,615 (73 ) (1 ) Consolidated net income $ 121,238 $ 113,265 $ 7,973 7 %

Derivative Financial Instrume34

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Interest Rate Cap Derivative Summary	Below is a summary of the interest rate cap derivatives held by the Company as of September 30, 2015 : (Dollars in thousands) Notional Accounting Fair Value as of Effective Date Maturity Date Amount Treatment September 30, 2015 May 3, 2012 May 3, 2016 215,000 Non-Hedge Designated — August 29, 2012 August 29, 2016 216,500 Cash Flow Hedging 5 February 22, 2013 August 22, 2016 43,500 Cash Flow Hedging 2 February 22, 2013 August 22, 2016 56,500 Non-Hedge Designated 2 March 21, 2013 March 21, 2017 100,000 Non-Hedge Designated 69 May 16, 2013 November 16, 2016 75,000 Non-Hedge Designated 13 September 15, 2013 September 15, 2017 50,000 Cash Flow Hedging 112 September 30, 2013 September 30, 2017 40,000 Cash Flow Hedging 97 $ 796,500 $ 300
Schedule Of Fair Value Of Derivative Financial Instruments	The table below presents the fair value of the Company’s derivative financial instruments as of September 30, 2015 , December 31, 2014 and September 30, 2014 : Derivative Assets Derivative Liabilities Fair Value Fair Value (Dollars in thousands) September 30, 2015 December 31, 2014 September 30, 2014 September 30, 2015 December 31, 2014 September 30, 2014 Derivatives designated as hedging instruments under ASC 815: Interest rate derivatives designated as Cash Flow Hedges $ 216 $ 1,390 $ 1,947 $ 1,329 $ 1,994 $ 2,202 Interest rate derivatives designated as Fair Value Hedges 5 52 79 291 — — Total derivatives designated as hedging instruments under ASC 815 $ 221 $ 1,442 $ 2,026 $ 1,620 $ 1,994 $ 2,202 Derivatives not designated as hedging instruments under ASC 815: Interest rate derivatives $ 56,717 $ 36,399 $ 31,249 $ 55,809 $ 34,927 $ 29,249 Interest rate lock commitments 11,836 10,028 10,010 — 20 31 Forward commitments to sell mortgage loans — 23 41 7,713 4,239 3,986 Foreign exchange contracts 260 72 17 56 — 37 Total derivatives not designated as hedging instruments under ASC 815 $ 68,813 $ 46,522 $ 41,317 $ 63,578 $ 39,186 $ 33,303 Total Derivatives $ 69,034 $ 47,964 $ 43,343 $ 65,198 $ 41,180 $ 35,505
Schedule Of Cash Flow Hedging Instruments	The table below provides details on each of these cash flow hedges as of September 30, 2015 : September 30, 2015 (Dollars in thousands) Notional Fair Value Maturity Date Amount Asset (Liability) Interest Rate Swaps: September 2016 50,000 (862 ) October 2016 25,000 (467 ) Total Interest Rate Swaps 75,000 (1,329 ) Interest Rate Caps: August 2016 43,500 2 August 2016 216,500 5 September 2017 50,000 112 September 2017 40,000 97 Total Interest Rate Caps 350,000 216 Total Cash Flow Hedges $ 425,000 $ (1,113 )
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 loss related to interest rate derivatives designated as cash flow hedges follows: Three months ended Nine months ended (Dollars in thousands) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Unrealized loss at beginning of period $ (4,408 ) $ (4,695 ) $ (4,062 ) $ (3,971 ) Amount reclassified from accumulated other comprehensive loss to interest expense on deposits and junior subordinated debentures 571 553 1,460 1,567 Amount of loss recognized in other comprehensive income (503 ) 418 (1,738 ) (1,320 ) Unrealized loss at end of period $ (4,340 ) $ (3,724 ) $ (4,340 ) $ (3,724 )
Derivatives Used To Hedge Changes In Fair Value Attributable To Interest Rate Risk	The following table presents the gain/(loss) and hedge ineffectiveness recognized on derivative instruments and the related hedged items that are designated as a fair value hedge accounting relationship as of September 30, 2015 and 2014: (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location of Gain/(Loss) Recognized in Income on Derivative Amount of Gain/(Loss) Recognized in Income on Derivative Three Months Ended Amount of (Loss)/Gain Recognized in Income on Hedged Item Three Months Ended Income Statement Gain/ (Loss) due to Hedge Ineffectiveness Three Months Ended September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Interest rate swaps Trading (losses) gains, net $ (323 ) $ 16 $ 302 $ (16 ) $ (21 ) $ — (Dollars in thousands) Derivatives in Fair Value Hedging Relationships Location of Gain/(Loss) Recognized in Income on Derivative Amount of Losses Recognized in Income on Derivative Nine Months Ended Amount of Gains Recognized in Income on Hedged Item Nine Months Ended Income Statement Losses due to Hedge Ineffectiveness Nine Months Ended September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Interest rate swaps Trading (losses) gains, net $ (338 ) $ (27 ) $ 315 $ 24 $ (23 ) $ (3 )
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) Three Months Ended Nine Months Ended Derivative Location in income statement September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Interest rate swaps and caps Trading (losses) gains, net $ (275 ) $ 270 $ (592 ) $ (1,144 ) Mortgage banking derivatives Mortgage banking revenue (4,062 ) (562 ) (1,669 ) (1,770 ) Covered call options Fees from covered call options 2,810 2,107 11,735 4,893 Foreign exchange contracts Trading (losses) gains, net 113 (12 ) 133 (23 )
Derivative Asset and Liability Balance Sheet Offsetting	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) September 30, 2015 December 31, 2014 September 30, 2014 September 30, 2015 December 31, 2014 September 30, 2014 Gross Amounts Recognized $ 56,938 $ 37,841 $ 33,275 $ 57,429 $ 36,921 $ 31,451 Less: Amounts offset in the Statements of Financial Condition — — — — — — Net amount presented in the Statements of Financial Condition $ 56,938 $ 37,841 $ 33,275 $ 57,429 $ 36,921 $ 31,451 Gross amounts not offset in the Statements of Financial Condition Offsetting Derivative Positions (614 ) (2,771 ) (5,417 ) (614 ) (2,771 ) (5,417 ) Collateral Posted (1) — — — (54,410 ) (34,150 ) (26,034 ) Net Credit Exposure $ 56,324 $ 35,070 $ 27,858 $ 2,405 $ — $ — (1) As of December 31, 2014 and September 30, 2014, the Company posted collateral of $43.8 million and $33.9 million , respectively, which resulted in excess collateral with its counterparties. For purposes of this disclosure, the amount of posted collateral is limited to the amount offsetting the derivative liability.

Fair Values of Assets and Lia35

Fair Values of Assets and Liabilities (Tables)	9 Months Ended
	Sep. 30, 2015
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: September 30, 2015 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 285,922 $ — $ 285,922 $ — U.S. Government agencies 645,023 — 645,023 — Municipal 297,342 — 228,941 68,401 Corporate notes 116,945 — 116,945 — Mortgage-backed 815,045 — 815,045 — Equity securities 54,004 — 29,488 24,516 Trading account securities 3,312 — 3,312 — Mortgage loans held-for-sale 347,005 — 347,005 — Mortgage servicing rights 7,875 — — 7,875 Nonqualified deferred compensation assets 8,342 — 8,342 — Derivative assets 69,034 — 69,034 — Total $ 2,649,849 $ — $ 2,549,057 $ 100,792 Derivative liabilities $ 65,198 $ — $ 65,198 $ — December 31, 2014 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 381,805 $ — $ 381,805 $ — U.S. Government agencies 668,316 — 668,316 — Municipal 238,529 — 179,576 58,953 Corporate notes 133,579 — 133,579 — Mortgage-backed 318,710 — 318,710 — Equity securities 51,139 — 27,428 23,711 Trading account securities 1,206 — 1,206 — Mortgage loans held-for-sale 351,290 — 351,290 — Mortgage servicing rights 8,435 — — 8,435 Nonqualified deferred compensation assets 7,951 — 7,951 — Derivative assets 47,964 — 47,964 — Total $ 2,208,924 $ — $ 2,117,825 $ 91,099 Derivative liabilities $ 41,180 $ — $ 41,180 $ — September 30, 2014 (Dollars in thousands) Total Level 1 Level 2 Level 3 Available-for-sale securities U.S. Treasury $ 378,261 $ — $ 378,261 $ — U.S. Government agencies 739,752 — 739,752 — Municipal 187,103 — 136,866 50,237 Corporate notes 134,155 — 134,155 — Mortgage-backed 291,222 — 291,222 — Equity securities 52,155 — 28,194 23,961 Trading account securities 6,015 — 6,015 — Mortgage loans held-for-sale 363,303 — 363,303 — Mortgage servicing rights 8,137 — — 8,137 Nonqualified deferred compensation assets 7,927 — 7,927 — Derivative assets 43,343 — 43,343 — Total $ 2,211,373 $ — $ 2,129,038 $ 82,335 Derivative liabilities $ 35,505 $ — $ 35,505 $ —
Summary Of Changes In Level 3 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 three and nine months ended September 30, 2015 and 2014 are summarized as follows: Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at July 1, 2015 $ 58,572 $ 24,996 $ 8,034 Total net gains (losses) included in: Net income (1) — — (159 ) Other comprehensive income 223 (480 ) — Purchases 10,405 — — Issuances — — — Sales — — — Settlements (799 ) — — Net transfers into/(out of) Level 3 — — — Balance at September 30, 2015 $ 68,401 $ 24,516 $ 7,875 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at January 1, 2015 $ 58,953 $ 23,711 $ 8,435 Total net gains (losses) included in: Net income (1) — — (560 ) Other comprehensive income (287 ) 805 — Purchases 21,254 — — Issuances — — — Sales — — — Settlements (11,519 ) — — Net transfers into/(out of) Level 3 — — — Balance at September 30, 2015 $ 68,401 $ 24,516 $ 7,875 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at July 1, 2014 $ 38,053 $ 24,152 $ 8,227 Total net gains (losses) included in: Net income (1) — — (90 ) Other comprehensive income (27 ) (191 ) — Purchases 4,129 — — Issuances — — — Sales — — — Settlements (800 ) — — Net transfers into/(out of) Level 3 (2) 8,882 — — Balance at September 30, 2014 $ 50,237 $ 23,961 $ 8,137 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. (2) Transfers into Level 3 relate to a reclassification of municipal bonds in the current quarter. Equity securities Mortgage servicing rights (Dollars in thousands) Municipal Balance at January 1, 2014 $ 36,386 $ 22,163 $ 8,946 Total net gains (losses) included in: Net income (1) — — (809 ) Other comprehensive income 193 1,798 — Purchases 9,095 — — Issuances — — — Sales — — — Settlements (4,319 ) — — Net transfers into/(out of) Level 3 (2) 8,882 — — Balance at September 30, 2014 $ 50,237 $ 23,961 $ 8,137 (1) Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income. (2) Transfers into Level 3 relate to a reclassification of municipal bonds in the current quarter.
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 September 30, 2015 . September 30, 2015 Three Months Ended September 30, 2015 Fair Value Losses Recognized, net Nine Months Ended September 30, 2015 Fair Value Losses Recognized, net (Dollars in thousands) Total Level 1 Level 2 Level 3 Impaired loans—collateral based $ 73,819 $ — $ — $ 73,819 $ 5,262 $ 11,517 Other real estate owned, including covered other real estate owned (1) 80,524 — — 80,524 989 4,834 Total $ 154,343 $ — $ — $ 154,343 $ 6,251 $ 16,351 (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 Non-Recurring	The valuation techniques and significant unobservable inputs used to measure both recurring and non-recurring Level 3 fair value measurements at September 30, 2015 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 $ 68,401 Bond pricing Equivalent rating BBB-AA+ N/A Increase Equity Securities 24,516 Discounted cash flows Discount rate 2.01%-2.43% 2.22% Decrease Mortgage Servicing Rights 7,875 Discounted cash flows Discount rate 9%-13% 9.15% Decrease Constant prepayment rate (CPR) 9%-29% 12.93% Decrease Measured at fair value on a non-recurring basis: Impaired loans—collateral based $ 73,819 Appraisal value Appraisal adjustment - cost of sale 10% 10.00% Decrease Other real estate owned, including covered other real estate owned 80,524 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: At September 30, 2015 At December 31, 2014 At September 30, 2014 Carrying Fair Carrying Fair Carrying Fair (Dollars in thousands) Value Value Value Value Value Value Financial Assets: Cash and cash equivalents $ 250,655 $ 250,655 $ 230,707 $ 230,707 $ 287,416 $ 287,416 Interest bearing deposits with banks 701,106 701,106 998,437 998,437 620,370 620,370 Available-for-sale securities 2,214,281 2,214,281 1,792,078 1,792,078 1,782,648 1,782,648 Trading account securities 3,312 3,312 1,206 1,206 6,015 6,015 Federal Home Loan Bank and Federal Reserve Bank stock, at cost 90,308 90,308 91,582 91,582 80,951 80,951 Brokerage customer receivables 28,293 28,293 24,221 24,221 26,624 26,624 Mortgage loans held-for-sale, at fair value 347,005 347,005 351,290 351,290 363,303 363,303 Total loans 16,484,820 17,284,375 14,636,107 15,346,266 14,306,664 15,001,394 Mortgage servicing rights 7,875 7,875 8,435 8,435 8,137 8,137 Nonqualified deferred compensation assets 8,342 8,342 7,951 7,951 7,927 7,927 Derivative assets 69,034 69,034 47,964 47,964 43,343 43,343 FDIC indemnification asset — — 11,846 11,846 27,359 27,359 Accrued interest receivable and other 192,572 192,572 169,156 169,156 170,517 170,517 Total financial assets $ 20,397,603 $ 21,197,158 $ 18,370,980 $ 19,081,139 $ 17,731,274 $ 18,426,004 Financial Liabilities Non-maturity deposits $ 14,092,697 $ 14,092,697 $ 12,142,034 $ 12,142,034 $ 11,761,825 $ 11,761,825 Deposits with stated maturities 4,135,772 4,137,856 4,139,810 4,143,161 4,303,421 4,303,717 Federal Home Loan Bank advances 451,330 459,154 733,050 738,113 347,500 352,516 Other borrowings 259,978 259,978 196,465 197,883 51,483 51,483 Subordinated notes 140,000 142,953 140,000 143,639 140,000 142,720 Junior subordinated debentures 268,566 268,058 249,493 250,305 249,493 250,452 Derivative liabilities 65,198 65,198 41,180 41,180 35,505 35,505 Accrued interest payable 11,364 11,364 8,001 8,001 8,995 8,995 Total financial liabilities $ 19,424,905 $ 19,437,258 $ 17,650,033 $ 17,664,316 $ 16,898,222 $ 16,907,213

Stock-Based Compensation Plans

Stock-Based Compensation Plans (Tables)	9 Months Ended
	Sep. 30, 2015
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 nine month periods ending September 30, 2015 and 2014 . Nine Months Ended September 30, September 30, 2015 2014 Expected dividend yield 0.9 % 0.4 % Expected volatility 26.5 % 30.8 % Risk-free rate 1.3 % 0.7 % Expected option life (in years) 4.5 4.5
Summary Of Stock Option Activity	A summary of the Company's stock option activity for the nine months ended September 30, 2015 and September 30, 2014 is presented below: Stock Options Common Shares Weighted Average Strike Price Remaining Contractual Term (1) Intrinsic Value (2) ($000) Outstanding at January 1, 2015 1,618,426 $ 43.00 Conversion of options of acquired company 16,364 21.18 Granted 502,517 44.36 Exercised (258,836 ) 43.14 Forfeited or canceled (277,150 ) 53.64 Outstanding at September 30, 2015 1,601,321 $ 41.34 4.7 $ 19,378 Exercisable at September 30, 2015 715,101 $ 37.52 3.2 $ 11,376 Stock Options Common Shares Weighted Average Strike Price Remaining Contractual Term (1) Intrinsic Value (2) ($000) Outstanding at January 1, 2014 1,524,672 $ 42.00 Granted 366,478 46.85 Exercised (139,928 ) 33.90 Forfeited or canceled (99,147 ) 50.61 Outstanding at September 30, 2014 1,652,075 $ 43.24 3.4 $ 8,133 Exercisable at September 30, 2014 1,050,665 $ 43.86 2.1 $ 5,851 (1) Represents the remaining weighted average contractual life in years. (2) Aggregate intrinsic value represents the total pre-tax intrinsic value (i.e., the difference between the Company's stock price on the last trading day of the quarter 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 quarter. Options with exercise prices above the stock price on the last trading day of the quarter 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 And Performance-Vested Stock Award Activity	A summary of the Plans' restricted share activity for the nine months ended September 30, 2015 and September 30, 2014 is presented below: Nine months ended September 30, 2015 Nine months ended September 30, 2014 Restricted Shares Common Shares Weighted Average Grant-Date Fair Value Common Shares Weighted Average Grant-Date Fair Value Outstanding at January 1 146,112 $ 47.45 181,522 $ 43.39 Granted 15,657 45.81 12,313 46.04 Vested and issued (20,409 ) 39.07 (51,978 ) 35.12 Forfeited (2,400 ) 36.81 (6,752 ) 37.95 Outstanding at September 30 138,960 $ 48.68 135,105 $ 47.09 Vested, but not issuable at September 30 85,000 $ 51.88 85,000 $ 51.88 A summary of the Plans' performance-based stock award activity, based on the target level of the awards, for the nine months ended September 30, 2015 and September 30, 2014 is presented below: Nine months ended September 30, 2015 Nine months ended September 30, 2014 Performance-based Stock Common Weighted Common Weighted Outstanding at January 1 295,679 $ 38.18 307,512 $ 34.01 Granted 106,017 44.35 93,535 46.85 Vested and issued (78,590 ) 31.10 (15,944 ) 33.25 Forfeited (33,854 ) 32.74 (89,424 ) 33.78 Outstanding at September 30 289,252 $ 43.00 295,679 $ 38.18

Shareholders' Equity and Earn37

Shareholders' Equity and Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]
Components Of Other Comprehensive Income (Loss)	The following tables summarize the components of other comprehensive income (loss), including the related income tax effects, and the related amount reclassified to net income for the periods presented (in thousands). Accumulated Unrealized Gains (Losses) on Securities Accumulated Unrealized Losses on Derivative Instruments Accumulated Foreign Currency Translation Adjustments Total Accumulated Other Comprehensive Loss Balance at July 1, 2015 $ (26,333 ) $ (2,727 ) $ (32,811 ) $ (61,871 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 18,995 (287 ) (6,337 ) 12,371 Amount reclassified from accumulated other comprehensive income (loss), net of tax 60 347 — 407 Net other comprehensive income (loss) during the period, net of tax $ 19,055 $ 60 $ (6,337 ) $ 12,778 Balance at September 30, 2015 $ (7,278 ) $ (2,667 ) $ (39,148 ) $ (49,093 ) Balance at January 1, 2015 $ (9,533 ) $ (2,517 ) $ (25,282 ) $ (37,332 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 2,499 (1,027 ) (13,866 ) (12,394 ) Amount reclassified from accumulated other comprehensive income (loss), net of tax (244 ) 877 — 633 Net other comprehensive income (loss) during the period, net of tax $ 2,255 $ (150 ) $ (13,866 ) $ (11,761 ) Balance at September 30, 2015 $ (7,278 ) $ (2,667 ) $ (39,148 ) $ (49,093 ) Balance at July 1, 2014 $ (24,003 ) $ (2,898 ) $ (7,602 ) $ (34,503 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 812 252 (9,685 ) (8,621 ) Amount reclassified from accumulated other comprehensive income (loss), net of tax 91 333 — 424 Net other comprehensive income (loss) during the period, net of tax $ 903 $ 585 $ (9,685 ) $ (8,197 ) Balance at September 30, 2014 $ (23,100 ) $ (2,313 ) $ (17,287 ) $ (42,700 ) Balance at January 1, 2014 $ (53,665 ) $ (2,462 ) $ (6,909 ) $ (63,036 ) Other comprehensive income (loss) during the period, net of tax, before reclassifications 30,251 (795 ) (10,378 ) 19,078 Amount reclassified from accumulated other comprehensive income (loss), net of tax 314 944 — 1,258 Net other comprehensive income (loss) during the period, net of tax $ 30,565 $ 149 $ (10,378 ) $ 20,336 Balance at September 30, 2014 $ (23,100 ) $ (2,313 ) $ (17,287 ) $ (42,700 )
Other Comprehensive Income Reclassified from AOCI	Amount Reclassified from Accumulated Other Comprehensive Income for the Details Regarding the Component of Accumulated Other Comprehensive Income Three Months Ended Nine Months Ended Impacted Line on the Consolidated Statements of Income September 30, September 30, 2015 2014 2015 2014 Accumulated unrealized losses on securities (Losses) gains included in net income $ (98 ) $ (153 ) $ 402 $ (522 ) (Losses) gains on available-for-sale securities, net (98 ) (153 ) 402 (522 ) Income before taxes Tax effect $ 38 $ 62 $ (158 ) $ 208 Income tax expense Net of tax $ (60 ) $ (91 ) $ 244 $ (314 ) Net income Accumulated unrealized losses on derivative instruments Amount reclassified to interest expense on deposits $ 92 $ — $ 92 $ — Interest on deposits Amount reclassified to interest expense on junior subordinated debentures 479 553 $ 1,350 $ 1,567 Interest on junior subordinated debentures (571 ) (553 ) (1,442 ) (1,567 ) Income before taxes Tax effect $ 224 $ 220 $ 565 $ 623 Income tax expense Net of tax $ (347 ) $ (333 ) $ (877 ) $ (944 ) Net income
Computation Of Basic And Diluted Earnings Per Common Share	The following table shows the computation of basic and diluted earnings per share for the periods indicated: Three Months Ended Nine Months Ended (In thousands, except per share data) September 30, 2015 September 30, 2014 September 30, 2015 September 30, 2014 Net income $ 38,355 $ 40,224 $ 121,238 $ 113,265 Less: Preferred stock dividends and discount accretion 4,079 1,581 7,240 4,743 Net income applicable to common shares—Basic (A) 34,276 38,643 113,998 108,522 Add: Dividends on convertible preferred stock, if dilutive 1,579 1,581 4,740 4,743 Net income applicable to common shares—Diluted (B) 35,855 40,224 118,738 113,265 Weighted average common shares outstanding (C) 48,158 46,639 47,658 46,453 Effect of dilutive potential common shares Common stock equivalents 978 1,166 1,070 1,274 Convertible preferred stock, if dilutive 3,071 3,075 3,071 3,075 Total dilutive potential common shares 4,049 4,241 4,141 4,349 Weighted average common shares and effect of dilutive potential common shares (D) 52,207 50,880 51,799 50,802 Net income per common share: Basic (A/C) $ 0.71 $ 0.83 $ 2.39 $ 2.34 Diluted (B/D) $ 0.69 $ 0.79 $ 2.29 $ 2.23

Business Combinations (Summary

Business Combinations (Summary of FDIC Indemnification Asset) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
FDIC Indemnification Asset [Roll Forward]
Balance at beginning of period	$ 3,429	$ 46,115	$ 11,846	$ 85,672
Additions from acquisitions	0	0	0	0
Additions from reimbursable expenses	1,039	1,584	3,548	4,933
Amortization	(718)	(1,382)	(3,184)	(4,441)
Changes in expected reimbursements from the FDIC for changes in expected credit losses	(5,236)	(12,124)	(13,546)	(41,153)
Payments received from the FDIC	(1,547)	(6,834)	(1,697)	(17,652)
Balance at end of period	0	$ 27,359	0	$ 27,359
Other Liabilities
FDIC Indemnification Asset [Roll Forward]
Balance at end of period	$ (3,033)		$ (3,033)

Business Combinations (Narrativ

Business Combinations (Narrative) (Detail)	Jul. 24, 2015USD ($)locations	Jul. 17, 2015USD ($)locations	Jul. 02, 2015USD ($)	Jan. 16, 2015USD ($)locations	Aug. 08, 2014USD ($)locations	Jul. 11, 2014USD ($)	May. 16, 2014USD ($)	Apr. 28, 2014USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2015financial_institution	Jul. 01, 2015USD ($)locations
Business Acquisition [Line Items]
Goodwill, Acquired During Period									$ 69,398,000
FDIC loss sharing percentage on purchased loans, OREO, and certain other assets									80.00%
Community Financial Shares, Inc.
Business Acquisition [Line Items]
Effective date of acquisition	Jul. 24, 2015
Number of locations | locations	4
Assets acquired	$ 350,500,000
Loans acquired	159,500,000
Assumed deposits	290,000,000
Goodwill, Acquired During Period	$ 27,500,000
Suburban Illinois Bancorp
Business Acquisition [Line Items]
Effective date of acquisition		Jul. 17, 2015
Number of locations | locations		10
Assets acquired		$ 494,700,000
Loans acquired		257,800,000
Assumed deposits		416,700,000
Goodwill, Acquired During Period		$ 18,800,000
North Bank
Business Acquisition [Line Items]
Effective date of acquisition			Jul. 1, 2015
Number of locations | locations											2
Assets acquired											$ 101,000,000
Loans acquired											51,600,000
Assumed deposits											$ 100,300,000
Goodwill, Acquired During Period			$ 6,700,000
Delavan Bancshares
Business Acquisition [Line Items]
Effective date of acquisition				Jan. 16, 2015
Number of locations | locations				4
Assets acquired				$ 224,100,000
Loans acquired				128,000,000
Assumed deposits				170,200,000
Liabilities assumed				186,400,000
Goodwill, Acquired During Period				$ 16,300,000
Talmer Bank & Trust
Business Acquisition [Line Items]
Effective date of acquisition					Aug. 8, 2014
Number of locations | locations					11
Assets acquired					$ 361,300,000
Loans acquired					41,500,000
Assumed deposits					354,900,000
Liabilities assumed					361,300,000
Goodwill, Acquired During Period					$ 9,700,000
THE National Bank
Business Acquisition [Line Items]
Effective date of acquisition						Jul. 11, 2014
Assets acquired						$ 94,100,000
Loans acquired						75,000,000
Assumed deposits						36,200,000
Goodwill, Acquired During Period						$ 16,300,000
Urban Partnership Bank, Stone Park branch
Business Acquisition [Line Items]
Effective date of acquisition							May 16, 2014
Assumed deposits							$ 5,400,000
Liabilities assumed							5,500,000
Goodwill, Acquired During Period							$ 678,000
FDIC Assisted
Business Acquisition [Line Items]
Number of FDIC assisted banks acquired | financial_institution										9
Policy Billing Services Inc. And Equity Premium Finance Inc.
Business Acquisition [Line Items]
Effective date of acquisition								Apr. 28, 2014
Loans acquired								$ 7,400,000
Goodwill, Acquired During Period								$ 6,500,000
Number of affiliated companies acquired								2

Available-For-Sale Securities40

Available-For-Sale Securities (Schedule of Available-for-Sale Securities Reconciliation) (Detail) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		$ 2,226,376	$ 1,807,913	$ 1,821,033
Gross Unrealized Gains		20,153	22,145	21,156
Gross Unrealized Losses		(32,248)	(37,980)	(59,541)
Available-for-sale Securities		2,214,281	1,792,078	1,782,648
U.S. Treasury
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		288,185	388,713	388,873
Gross Unrealized Gains		101	84	372
Gross Unrealized Losses		(2,364)	(6,992)	(10,984)
Available-for-sale Securities		285,922	381,805	378,261
U.S. Government agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		657,297	686,106	771,255
Gross Unrealized Gains		2,726	4,113	3,866
Gross Unrealized Losses		(15,000)	(21,903)	(35,369)
Available-for-sale Securities		645,023	668,316	739,752
Municipal
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		294,073	234,951	184,015
Gross Unrealized Gains		5,354	5,318	4,969
Gross Unrealized Losses		(2,085)	(1,740)	(1,881)
Available-for-sale Securities		297,342	238,529	187,103
Corporate notes, Financial issuers
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		114,976	129,309	129,259
Gross Unrealized Gains		1,656	2,006	2,252
Gross Unrealized Losses		(1,216)	(1,557)	(1,208)
Available-for-sale Securities		115,416	129,758	130,303
Corporate notes, Other
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,525	3,766	3,773
Gross Unrealized Gains		6	55	79
Gross Unrealized Losses		(2)	0	0
Available-for-sale Securities		1,529	3,821	3,852
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	[1]	778,240	271,129	246,354
Gross Unrealized Gains	[1]	4,974	5,448	4,303
Gross Unrealized Losses	[1]	(10,913)	(4,928)	(8,938)
Available-for-sale Securities	[1]	772,301	271,649	241,719
Mortgage-backed, Collateralized mortgage obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	[1]	42,724	47,347	49,909
Gross Unrealized Gains	[1]	343	249	357
Gross Unrealized Losses	[1]	(323)	(535)	(763)
Available-for-sale Securities	[1]	42,744	47,061	49,503
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		49,356	46,592	47,595
Gross Unrealized Gains		4,993	4,872	4,958
Gross Unrealized Losses		(345)	(325)	(398)
Available-for-sale Securities		54,004	51,139	52,155
Mortgage-backed securities, subprime
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities		$ 0	$ 0	$ 0
[1]	Consisting entirely of residential mortgage-backed securities, none of which are subprime.

Available-For-Sale Securities41

Available-For-Sale Securities (Available-For-Sale Securities, Continuous Unrealized Loss Position, Fair Value) (Detail) $ in Thousands	Sep. 30, 2015USD ($)
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	$ 1,043,038
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(15,500)
Continuous unrealized losses existing for greater than 12 months, Fair value	471,988
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	(16,748)
Total, Fair value	1,515,026
Total, Unrealized losses	(32,248)
U.S. Treasury
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	202,795
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(2,364)
Continuous unrealized losses existing for greater than 12 months, Fair value	0
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	0
Total, Fair value	202,795
Total, Unrealized losses	(2,364)
U.S. Government agencies
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	218,297
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(4,932)
Continuous unrealized losses existing for greater than 12 months, Fair value	251,654
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	(10,068)
Total, Fair value	469,951
Total, Unrealized losses	(15,000)
Municipal
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	68,140
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(964)
Continuous unrealized losses existing for greater than 12 months, Fair value	37,002
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	(1,121)
Total, Fair value	105,142
Total, Unrealized losses	(2,085)
Corporate notes, Financial issuers
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	23,052
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(152)
Continuous unrealized losses existing for greater than 12 months, Fair value	44,894
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	(1,064)
Total, Fair value	67,946
Total, Unrealized losses	(1,216)
Corporate notes, Other
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	999
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(2)
Continuous unrealized losses existing for greater than 12 months, Fair value	0
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	0
Total, Fair value	999
Total, Unrealized losses	(2)
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	519,631
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(7,011)
Continuous unrealized losses existing for greater than 12 months, Fair value	120,261
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	(3,902)
Total, Fair value	639,892
Total, Unrealized losses	(10,913)
Mortgage-backed, Collateralized mortgage obligations
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	7,167
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(63)
Continuous unrealized losses existing for greater than 12 months, Fair value	9,620
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	(260)
Total, Fair value	16,787
Total, Unrealized losses	(323)
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Continuous unrealized losses existing for less than 12 months, Fair value	2,957
Continuous unrealized losses existing for less than 12 months, Unrealized losses	(12)
Continuous unrealized losses existing for greater than 12 months, Fair value	8,557
Continuous unrealized losses existing for greater than 12 months, Unrealized losses	(333)
Total, Fair value	11,514
Total, Unrealized losses	$ (345)

Available-For-Sale Securities42

Available-For-Sale Securities (Schedule of Realized Gain (Loss)) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Available-for-sale Securities [Abstract]
Realized gains	$ 87	$ 179	$ 654	$ 333
Realized losses	(185)	(332)	(252)	(855)
Net realized (losses) gains	(98)	(153)	402	(522)
Other than temporary impairment charges	0	0	0	0
(Losses) gains on available-for-sale securities, net	(98)	(153)	402	(522)
Proceeds from sales of available-for-sale securities	$ 82,827	$ 382,552	$ 1,216,860	$ 578,594

Available-For-Sale Securities43

Available-For-Sale Securities (Investments Classified by Contractual Maturity Date) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Due in one year or less, Amortized Cost	$ 164,374	$ 285,596	$ 216,244
Due in one to five years, Amortized Cost	186,199	172,647	309,914
Due in five to ten years, Amortized Cost	343,468	331,389	327,505
Due after ten years, Amortized Cost	662,015	653,213	623,512
Amortized Cost	2,226,376	1,807,913	1,821,033
Due in one year or less, Fair Value	164,429	285,889	216,582
Due in one to five years, Fair Value	186,592	172,885	310,917
Due in five to ten years, Fair Value	342,271	325,644	317,654
Due after ten years, Fair Value	651,940	637,811	594,118
Available-for-sale securities, at fair value	2,214,281	1,792,078	1,782,648
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	820,964	318,476	296,263
Available-for-sale securities, at fair value	815,045	318,710	291,222
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	49,356	46,592	47,595
Available-for-sale securities, at fair value	$ 54,004	$ 51,139	$ 52,155

Available-For-Sale Securities44

Available-For-Sale Securities (Narrative) (Detail) $ in Billions	Sep. 30, 2015USD ($)securities	Dec. 31, 2014USD ($)	Sep. 30, 2014USD ($)
Available-for-sale Securities [Abstract]
Pledged Securities, carrying value	$ 1.3	$ 1.1	$ 1.1
Number of securities by a single non-goverment sponsored issuer exceeding 10% of shareholders' equity | securities	0

Loans (Summary of Loan Portfoli

Loans (Summary of Loan Portfolio) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 16,316,211	$ 14,409,398	$ 14,052,059
Covered loans	168,609	226,709	254,605
Total loans	$ 16,484,820	$ 14,636,107	$ 14,306,664
Total loans, net of unearned income, excluding covered loans, percentage	99.00%	98.00%	98.00%
Covered loans, percentage	1.00%	2.00%	2.00%
Total loans, percentage	100.00%	100.00%	100.00%
Commercial
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 4,400,185	$ 3,924,394	$ 3,689,671
Total loans, net of unearned income, excluding covered loans, percentage	27.00%	26.00%	26.00%
Commercial real estate
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 5,307,566	$ 4,505,753	$ 4,510,375
Total loans, net of unearned income, excluding covered loans, percentage	32.00%	31.00%	31.00%
Home equity
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 797,465	$ 716,293	$ 720,058
Total loans, net of unearned income, excluding covered loans, percentage	5.00%	5.00%	5.00%
Residential real estate
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 571,743	$ 483,542	$ 470,319
Total loans, net of unearned income, excluding covered loans, percentage	3.00%	3.00%	3.00%
Consumer and other
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 131,902	$ 151,012	$ 149,339
Total loans, net of unearned income, excluding covered loans, percentage	1.00%	1.00%	1.00%
Commercial insurance loans | Premium finance receivables
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 2,407,075	$ 2,350,833	$ 2,377,892
Total loans, net of unearned income, excluding covered loans, percentage	15.00%	16.00%	17.00%
Life insurance | Premium finance receivables
Loans [Line Items]
Loans, net of unearned income, excluding covered loans	$ 2,700,275	$ 2,277,571	$ 2,134,405
Total loans, net of unearned income, excluding covered loans, percentage	16.00%	16.00%	15.00%

Loans (Schedule of Unpaid Princ

Loans (Schedule of Unpaid Principal Balance And Carrying Value Of Acquired Loans) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Bank acquisitions
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Unpaid Principal Balance	$ 356,615	$ 285,809
Carrying Value	295,801	227,229
Life insurance premium finance loans acquisition
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Unpaid Principal Balance	378,040	399,665
Carrying Value	$ 373,586	$ 393,479

Loans Loans (Certain Loans Acqu

Loans Loans (Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period) (Details) - USD ($) $ in Thousands		Jul. 24, 2015	Jul. 17, 2015	Jul. 01, 2015	Jan. 16, 2015
North Bank
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Contractually required payments including interest				$ 8,563
Less: Nonaccretable difference				1,027
Cash flows expected to be collected	[1]			7,536
Less: Accretable yield				866
Fair value of PCI loans acquired				$ 6,670
Community Financial Shares, Inc.
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Contractually required payments including interest		$ 38,656
Less: Nonaccretable difference		4,437
Cash flows expected to be collected	[1]	34,219
Less: Accretable yield		2,895
Fair value of PCI loans acquired		$ 31,324
Suburban Illinois Bancorp
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Contractually required payments including interest			$ 95,804
Less: Nonaccretable difference			13,888
Cash flows expected to be collected	[1]		81,916
Less: Accretable yield			5,334
Fair value of PCI loans acquired			$ 76,582
Delavan Bancshares
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Contractually required payments including interest					$ 15,791
Less: Nonaccretable difference					1,442
Cash flows expected to be collected	[1]				14,349
Less: Accretable yield					898
Fair value of PCI loans acquired					$ 13,451
[1]	Represents undiscounted expected principal and interest cash at acquisition.

Loans (Activity Related to Accr

Loans (Activity Related to Accretable Yield of Loans Acquired With Evidence of Credit Quality Deterioration Since Origination) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Accretable yield, beginning balance		$ 63,643	$ 97,281	$ 79,102	$ 115,909
Acquisitions		9,095	0	9,993	0
Accretable yield amortized to interest income		5,939	7,847	18,359	28,438
Accretable yield amortized to indemnification asset	[1]	3,280	8,784	10,945	25,593
Reclassification from non-accretable difference	[2]	2,298	2,584	5,154	29,092
Increases (decreases) in interest cash flows due to payments and changes in interest rates		(610)	4,675	262	(3,061)
Accretable yield, ending balance	[3]	65,207	$ 87,909	65,207	$ 87,909
Accretable yield, to be amortized to indemnification asset		$ 10,000		$ 10,000
[1]	Represents the portion of the current period accreted yield, resulting from lower expected losses, applied to reduce the loss share indemnification asset.
[2]	Reclassification is the result of subsequent increases in expected principal cash flows.
[3]	As of September 30, 2015, the Company estimates that the remaining accretable yield balance to be amortized to the indemnification asset for the bank acquisitions is $10.0 million. The remainder of the accretable yield related to bank acquisitions is expected to be amortized to interest income.

Loans (Narrative) (Detail)

Loans (Narrative) (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Schedule Of Accretable Yield Activity Related to Loans Acquired With Evidence Of Credit Quality Deterioration Since Origination Table [Line Items]
Deferred Discounts, Finance Charges and Interest Included in Receivables	$ (18,800,000)	$ (6,300,000)	$ (18,800,000)	$ (6,300,000)	$ 330,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion	(5,939,000)	(7,847,000)	(18,359,000)	(28,438,000)
Premium finance receivables
Schedule Of Accretable Yield Activity Related to Loans Acquired With Evidence Of Credit Quality Deterioration Since Origination Table [Line Items]
Loans and Leases Receivable, Deferred Income	$ 53,400,000	$ 44,800,000	$ 53,400,000	$ 44,800,000	$ 46,900,000

Allowance for Loan Losses, Al50

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 (Schedule of Aging of the Company's Loan Portfolio) (Detail) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		$ 84,145	$ 77,710	$ 79,822
90+ days and still accruing		30,185	37,987	49,547
Current		16,271,836	14,408,516	14,069,281
Loans, net of unearned income, excluding covered loans		16,316,211	14,409,398	14,052,059
Nonaccrual		77,605	70,420	73,780
90+ days and still accruing		22,559	20,148	23,377
Current		16,119,587	14,213,075	13,856,832
Covered loans, Nonaccrual		6,540	7,290	6,042
Covered loans, 90 plus days and still accruing		7,626	17,839	26,170
Covered loans, Current		152,249	195,441	212,449
Covered loans		168,609	226,709	254,605
Total loans		16,484,820	14,636,107	14,306,664
60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		40,421	39,281	35,958
60-89 days past due		39,029	37,977	31,669
Covered loans, 60-89 days past due		1,392	1,304	4,289
30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		58,233	72,613	72,056
30-59 days past due		57,431	67,778	66,401
Covered loans, 30-59 days past due		802	4,835	5,655
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		12,018	9,157	10,455
90+ days and still accruing		217	839	863
Current		4,373,322	3,897,717	3,656,860
Loans, net of unearned income, excluding covered loans		4,400,185	3,924,394	3,689,671
Commercial | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		4,168	5,123	10,356
Commercial | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		10,460	11,558	11,137
Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		12,006	9,132	10,430
90+ days and still accruing		0	474	0
Current		2,622,207	2,213,105	2,044,505
Loans, net of unearned income, excluding covered loans		2,646,275	2,233,364	2,070,827
Commercial | Commercial and industrial | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,731	3,161	7,333
Commercial | Commercial and industrial | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		9,331	7,492	8,559
Commercial | Franchise
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		221,545	231,789	237,079
Loans, net of unearned income, excluding covered loans		222,001	233,316	238,300
Commercial | Franchise | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		80	308	0
Commercial | Franchise | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		376	1,219	1,221
Commercial | Mortgage warehouse lines of credit
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		136,614	139,003	121,585
Loans, net of unearned income, excluding covered loans		136,614	139,003	121,585
Commercial | Mortgage warehouse lines of credit | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | Mortgage warehouse lines of credit | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | Community Advanatage - homeowners association
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		123,165	106,364	99,595
Loans, net of unearned income, excluding covered loans		123,209	106,364	99,595
Commercial | Community Advanatage - homeowners association | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		44	0	0
Commercial | Community Advanatage - homeowners association | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | Aircraft
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		5,993	8,065	6,146
Loans, net of unearned income, excluding covered loans		6,371	8,065	6,146
Commercial | Aircraft | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | Aircraft | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		378	0	0
Commercial | Asset-based lending
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		12	25	25
90+ days and still accruing		0	0	0
Current		800,798	802,608	777,723
Loans, net of unearned income, excluding covered loans		802,370	806,402	781,927
Commercial | Asset-based lending | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		1,313	1,375	2,959
Commercial | Asset-based lending | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		247	2,394	1,220
Commercial | Tax exempt
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		232,667	217,487	205,150
Loans, net of unearned income, excluding covered loans		232,667	217,487	205,150
Commercial | Tax exempt | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | Tax exempt | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		205,697	159,744	145,439
Loans, net of unearned income, excluding covered loans		205,786	160,136	145,439
Commercial | Leases | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	77	0
Commercial | Leases | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		89	315	0
Commercial | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		1,953	11,034	11,403
Loans, net of unearned income, excluding covered loans		1,953	11,034	11,403
Commercial | Other | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | Other | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial | PCI - commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	[1]	0	0	0
90+ days and still accruing	[1]	217	365	863
Current	[1]	22,683	8,518	8,235
Loans, net of unearned income, excluding covered loans	[1],[2]	22,939	9,223	9,299
Commercial | PCI - commercial | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	0	202	64
Commercial | PCI - commercial | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	39	138	137
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		28,617	26,605	27,363
90+ days and still accruing		13,547	10,976	14,294
Current		5,225,048	4,428,053	4,435,482
Loans, net of unearned income, excluding covered loans		5,307,566	4,505,753	4,510,375
Commercial real estate | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		16,334	12,232	5,497
Commercial real estate | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		24,020	27,887	27,739
Commercial real estate | Residential construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		60,130	38,370	30,237
Loans, net of unearned income, excluding covered loans		61,271	38,696	30,237
Commercial real estate | Residential construction | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	250	0
Commercial real estate | Residential construction | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		1,141	76	0
Commercial real estate | Commercial construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		31	230	425
90+ days and still accruing		0	0	0
Current		283,538	185,513	159,383
Loans, net of unearned income, excluding covered loans		285,963	187,766	159,808
Commercial real estate | Commercial construction | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	0
Commercial real estate | Commercial construction | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,394	2,023	0
Commercial real estate | Land
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		1,756	2,656	2,556
90+ days and still accruing		0	0	0
Current		75,113	86,779	94,449
Loans, net of unearned income, excluding covered loans		79,076	91,830	101,239
Commercial real estate | Land | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		0	0	1,316
Commercial real estate | Land | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,207	2,395	2,918
Commercial real estate | Office
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		4,045	7,288	7,366
90+ days and still accruing		0	0	0
Current		773,043	694,149	688,390
Loans, net of unearned income, excluding covered loans		790,311	705,432	699,340
Commercial real estate | Office | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		10,861	2,621	1,696
Commercial real estate | Office | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,362	1,374	1,888
Commercial real estate | Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		11,637	2,392	2,626
90+ days and still accruing		0	0	0
Current		622,804	617,820	624,669
Loans, net of unearned income, excluding covered loans		636,124	623,970	627,886
Commercial real estate | Industrial | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		786	0	224
Commercial real estate | Industrial | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		897	3,758	367
Commercial real estate | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		2,022	4,152	6,205
90+ days and still accruing		0	0	0
Current		781,463	723,919	715,568
Loans, net of unearned income, excluding covered loans		785,842	731,488	725,890
Commercial real estate | Retail | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		1,536	116	0
Commercial real estate | Retail | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		821	3,301	4,117
Commercial real estate | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		1,525	249	249
90+ days and still accruing		0	0	0
Current		684,878	603,323	674,610
Loans, net of unearned income, excluding covered loans		687,659	605,742	677,971
Commercial real estate | Multi-family | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		512	249	793
Commercial real estate | Multi-family | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		744	1,921	2,319
Commercial real estate | Mixed use and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		7,601	9,638	7,936
90+ days and still accruing		0	0	0
Current		1,797,516	1,443,853	1,407,659
Loans, net of unearned income, excluding covered loans		1,820,328	1,465,117	1,427,386
Commercial real estate | Mixed use and other | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,340	2,603	1,468
Commercial real estate | Mixed use and other | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		12,871	9,023	10,323
Commercial real estate | PCI - commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	[1]	0	0	0
90+ days and still accruing	[1]	13,547	10,976	14,294
Current	[1]	146,563	34,327	40,517
Loans, net of unearned income, excluding covered loans	[1],[2]	160,992	55,712	60,618
Commercial real estate | PCI - commercial real estate | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	299	6,393	0
Commercial real estate | PCI - commercial real estate | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	583	4,016	5,807
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		8,365	6,174	5,696
90+ days and still accruing		0	0	0
Current		784,165	705,623	710,584
Loans, net of unearned income, excluding covered loans		797,465	716,293	720,058
Home equity | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		811	983	1,181
Home equity | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		4,124	3,513	2,597
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, net of unearned income, excluding covered loans		571,743	483,542	470,319
Residential real estate | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		14,557	15,502	15,730
90+ days and still accruing		0	0	0
Current		551,292	459,224	448,528
Loans, net of unearned income, excluding covered loans		568,061	481,308	467,624
Residential real estate | Residential real estate | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		1,017	267	670
Residential real estate | Residential real estate | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		1,195	6,315	2,696
Residential real estate | PCI - residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	[1]	0	0	0
90+ days and still accruing	[1]	424	549	930
Current	[1]	2,524	1,685	1,735
Loans, net of unearned income, excluding covered loans	[1],[2]	3,682	2,234	2,695
Residential real estate | PCI - residential real estate | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	323	0	30
Residential real estate | PCI - residential real estate | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	411	0	0
Premium finance receivables | Commercial insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		13,751	12,705	14,110
90+ days and still accruing		8,231	7,665	7,115
Current		2,364,770	2,307,140	2,336,231
Loans, net of unearned income, excluding covered loans		2,407,075	2,350,833	2,377,892
Premium finance receivables | Commercial insurance loans | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		6,664	5,995	6,279
Premium finance receivables | Commercial insurance loans | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		13,659	17,328	14,157
Premium finance receivables | Life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		0	0	0
90+ days and still accruing		0	0	0
Current		2,314,406	1,870,669	1,712,328
Loans, net of unearned income, excluding covered loans		2,326,689	1,884,092	1,726,803
Premium finance receivables | Life insurance loans | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		9,656	13,084	7,533
Premium finance receivables | Life insurance loans | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		2,627	339	6,942
Premium finance receivables | PCI - life insurance loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	[1]	0	0	0
90+ days and still accruing	[1]	0	0	0
Current	[1]	373,586	393,479	407,602
Loans, net of unearned income, excluding covered loans	[1],[2]	373,586	393,479	407,602
Premium finance receivables | PCI - life insurance loans | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	0	0	0
Premium finance receivables | PCI - life insurance loans | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	[1]	0	0	0
Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual		297	277	426
90+ days and still accruing		140	119	175
Current		130,474	149,485	147,482
Loans, net of unearned income, excluding covered loans		131,902	151,012	149,339
Consumer and other | 60-89 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		56	293	123
Consumer and other | 30-59 days past due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		$ 935	$ 838	$ 1,133
[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.
[2]	PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 6 - Loans for further discussion of these purchased loans.

Allowance for Loan Losses, Al51

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 (Summary of Performance by Loan Class) (Detail) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		$ 16,316,211	$ 14,409,398	$ 14,052,059
Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		16,230,235	14,330,721	13,970,989
Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		85,976	78,677	81,070
Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		4,400,185	3,924,394	3,689,671
Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		4,388,167	3,914,763	3,679,216
Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		12,018	9,631	10,455
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		5,307,566	4,505,753	4,510,375
Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		5,278,949	4,479,148	4,483,012
Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		28,617	26,605	27,363
Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		797,465	716,293	720,058
Home equity | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		789,100	710,119	714,362
Home equity | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		8,365	6,174	5,696
Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		571,743	483,542	470,319
Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		131,902	151,012	149,339
Consumer and other | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		131,465	150,617	148,738
Consumer and other | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		437	395	601
Commercial and industrial | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,646,275	2,233,364	2,070,827
Commercial and industrial | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,634,269	2,223,758	2,060,397
Commercial and industrial | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		12,006	9,606	10,430
Franchise | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		222,001	233,316	238,300
Franchise | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		222,001	233,316	238,300
Franchise | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
Mortgage warehouse lines of credit | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		136,614	139,003	121,585
Mortgage warehouse lines of credit | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		136,614	139,003	121,585
Mortgage warehouse lines of credit | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
Community Advanatage - homeowners association | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		123,209	106,364	99,595
Community Advanatage - homeowners association | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		123,209	106,364	99,595
Community Advanatage - homeowners association | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
Aircraft | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		6,371	8,065	6,146
Aircraft | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		6,371	8,065	6,146
Aircraft | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
Asset-based lending | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		802,370	806,402	781,927
Asset-based lending | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		802,358	806,377	781,902
Asset-based lending | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		12	25	25
Tax exempt | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		232,667	217,487	205,150
Tax exempt | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		232,667	217,487	205,150
Tax exempt | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
Leases | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		205,786	160,136	145,439
Leases | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		205,786	160,136	145,439
Leases | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
Other | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,953	11,034	11,403
Other | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,953	11,034	11,403
Other | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
PCI - commercial | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	22,939	9,223	9,299
PCI - commercial | Commercial | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	22,939	9,223	9,299
PCI - commercial | Commercial | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	0	0	0
Residential construction | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		61,271	38,696	30,237
Residential construction | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		61,271	38,696	30,237
Residential construction | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
Commercial construction | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		285,963	187,766	159,808
Commercial construction | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		285,932	187,536	159,383
Commercial construction | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		31	230	425
Land | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		79,076	91,830	101,239
Land | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		77,320	89,174	98,683
Land | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,756	2,656	2,556
Office | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		790,311	705,432	699,340
Office | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		786,266	698,144	691,974
Office | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		4,045	7,288	7,366
Industrial | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		636,124	623,970	627,886
Industrial | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		624,487	621,578	625,260
Industrial | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		11,637	2,392	2,626
Retail | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		785,842	731,488	725,890
Retail | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		783,820	727,336	719,685
Retail | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,022	4,152	6,205
Multi-family | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		687,659	605,742	677,971
Multi-family | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		686,134	605,493	677,722
Multi-family | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,525	249	249
Mixed use and other | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,820,328	1,465,117	1,427,386
Mixed use and other | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		1,812,727	1,455,479	1,419,450
Mixed use and other | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		7,601	9,638	7,936
PCI - commercial real estate | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	160,992	55,712	60,618
PCI - commercial real estate | Commercial real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	160,992	55,712	60,618
PCI - commercial real estate | Commercial real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	0	0	0
Residential real estate | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		568,061	481,308	467,624
Residential real estate | Residential real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		553,504	465,806	451,894
Residential real estate | Residential real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		14,557	15,502	15,730
PCI - residential real estate | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	3,682	2,234	2,695
PCI - residential real estate | Residential real estate | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	3,682	2,234	2,695
PCI - residential real estate | Residential real estate | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	0	0	0
Commercial insurance loans | Premium finance receivables
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,407,075	2,350,833	2,377,892
Commercial insurance loans | Premium finance receivables | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,385,093	2,330,463	2,356,667
Commercial insurance loans | Premium finance receivables | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		21,982	20,370	21,225
Life insurance loans | Premium finance receivables
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,326,689	1,884,092	1,726,803
Life insurance loans | Premium finance receivables | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		2,326,689	1,884,092	1,726,803
Life insurance loans | Premium finance receivables | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans		0	0	0
PCI - life insurance loans | Premium finance receivables
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[1],[2]	373,586	393,479	407,602
PCI - life insurance loans | Premium finance receivables | Performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	373,586	393,479	407,602
PCI - life insurance loans | Premium finance receivables | Non-performing
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income, excluding covered loans	[2]	$ 0	$ 0	$ 0
[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.
[2]	PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 6 - Loans for further discussion of these purchased loans.

Allowance for Loan Losses, Al52

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 (Summary of Activity in the Allowance for Credit Losses) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses at beginning of period	$ 100,204	$ 92,253	$ 91,705	$ 96,922
Other adjustments	(153)	(335)	(494)	(588)
Reclassification from allowance for unfunded lending-related commitments	(42)	62	(151)	(102)
Charge-offs	(6,877)	(8,102)	(17,658)	(24,978)
Recoveries	1,199	1,113	5,043	3,620
Provision for credit losses	8,665	6,028	24,551	16,145
Allowance for loan losses at period end	102,996	91,019	102,996	91,019
Allowance for unfunded lending-related commitments at period end	926	822	926	822
Allowance for credit losses at period end	103,922	91,841	103,922	91,841
Allowance for credit losses at period end, Individually evaluated for impairment	8,526	6,660	8,526	6,660
Allowance for credit losses at period end, Collectively evaluated for impairment	94,435	84,962	94,435	84,962
Loans at period end, Individually evaluated for impairment	114,220	130,944	114,220	130,944
Loans at period end, Collectively evaluated for impairment	15,640,792	13,440,901	15,640,792	13,440,901
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses at period end	961	219	961	219
Loans at period end, Loans acquired with deteriorated credit quality	561,199	480,214	561,199	480,214
Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses at beginning of period	32,900	26,038	31,699	23,092
Other adjustments	(12)	(32)	(42)	(69)
Reclassification from allowance for unfunded lending-related commitments	0	0	0	0
Charge-offs	(964)	(832)	(2,884)	(3,864)
Recoveries	462	296	1,117	883
Provision for credit losses	1,604	2,442	4,100	7,870
Allowance for loan losses at period end	33,990	27,912	33,990	27,912
Allowance for unfunded lending-related commitments at period end	0	0	0	0
Allowance for credit losses at period end	33,990	27,912	33,990	27,912
Allowance for credit losses at period end, Individually evaluated for impairment	1,881	2,296	1,881	2,296
Allowance for credit losses at period end, Collectively evaluated for impairment	31,943	25,427	31,943	25,427
Loans at period end, Individually evaluated for impairment	18,211	16,568	18,211	16,568
Loans at period end, Collectively evaluated for impairment	4,359,035	3,663,804	4,359,035	3,663,804
Commercial | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses at period end	166	189	166	189
Loans at period end, Loans acquired with deteriorated credit quality	22,939	9,299	22,939	9,299
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses at beginning of period	42,198	40,702	35,533	48,658
Other adjustments	(85)	(265)	(346)	(482)
Reclassification from allowance for unfunded lending-related commitments	(42)	62	(151)	(102)
Charge-offs	(1,948)	(4,510)	(3,809)	(11,354)
Recoveries	213	275	2,349	762
Provision for credit losses	3,725	2,395	10,485	1,177
Allowance for loan losses at period end	44,061	38,659	44,061	38,659
Allowance for unfunded lending-related commitments at period end	926	822	926	822
Allowance for credit losses at period end	44,987	39,481	44,987	39,481
Allowance for credit losses at period end, Individually evaluated for impairment	5,832	3,507	5,832	3,507
Allowance for credit losses at period end, Collectively evaluated for impairment	38,361	35,967	38,361	35,967
Loans at period end, Individually evaluated for impairment	68,947	89,201	68,947	89,201
Loans at period end, Collectively evaluated for impairment	5,077,627	4,360,556	5,077,627	4,360,556
Commercial real estate | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses at period end	794	7	794	7
Loans at period end, Loans acquired with deteriorated credit quality	160,992	60,618	160,992	60,618
Home equity
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses at beginning of period	12,288	13,918	12,500	12,611
Other adjustments	0	(1)	0	(3)
Reclassification from allowance for unfunded lending-related commitments	0	0	0	0
Charge-offs	(1,116)	(748)	(3,547)	(3,745)
Recoveries	42	99	129	478
Provision for credit losses	1,009	(308)	3,141	3,619
Allowance for loan losses at period end	12,223	12,960	12,223	12,960
Allowance for unfunded lending-related commitments at period end	0	0	0	0
Allowance for credit losses at period end	12,223	12,960	12,223	12,960
Allowance for credit losses at period end, Individually evaluated for impairment	239	292	239	292
Allowance for credit losses at period end, Collectively evaluated for impairment	11,984	12,668	11,984	12,668
Loans at period end, Individually evaluated for impairment	8,365	5,922	8,365	5,922
Loans at period end, Collectively evaluated for impairment	789,100	714,136	789,100	714,136
Home equity | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses at period end	0	0	0	0
Loans at period end, Loans acquired with deteriorated credit quality	0	0	0	0
Residential real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses at beginning of period	5,019	3,733	4,218	5,108
Other adjustments	(6)	(2)	(14)	(6)
Reclassification from allowance for unfunded lending-related commitments	0	0	0	0
Charge-offs	(1,138)	(205)	(2,692)	(1,120)
Recoveries	136	111	228	316
Provision for credit losses	575	405	2,846	(256)
Allowance for loan losses at period end	4,586	4,042	4,586	4,042
Allowance for unfunded lending-related commitments at period end	0	0	0	0
Allowance for credit losses at period end	4,586	4,042	4,586	4,042
Allowance for credit losses at period end, Individually evaluated for impairment	544	512	544	512
Allowance for credit losses at period end, Collectively evaluated for impairment	4,042	3,530	4,042	3,530
Loans at period end, Individually evaluated for impairment	18,267	18,383	18,267	18,383
Loans at period end, Collectively evaluated for impairment	549,794	449,241	549,794	449,241
Residential real estate | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses at period end	0	0	0	0
Loans at period end, Loans acquired with deteriorated credit quality	3,682	2,695	3,682	2,695
Premium finance receivables
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses at beginning of period	6,921	6,309	6,513	5,583
Other adjustments	(50)	(35)	(92)	(28)
Reclassification from allowance for unfunded lending-related commitments	0	0	0	0
Charge-offs	(1,595)	(1,557)	(4,384)	(4,259)
Recoveries	294	290	1,081	925
Provision for credit losses	1,511	1,260	3,963	4,046
Allowance for loan losses at period end	7,081	6,267	7,081	6,267
Allowance for unfunded lending-related commitments at period end	0	0	0	0
Allowance for credit losses at period end	7,081	6,267	7,081	6,267
Allowance for credit losses at period end, Individually evaluated for impairment	0	0	0	0
Allowance for credit losses at period end, Collectively evaluated for impairment	7,081	6,267	7,081	6,267
Loans at period end, Individually evaluated for impairment	0	0	0	0
Loans at period end, Collectively evaluated for impairment	4,733,764	4,104,695	4,733,764	4,104,695
Premium finance receivables | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses at period end	0	0	0	0
Loans at period end, Loans acquired with deteriorated credit quality	373,586	407,602	373,586	407,602
Consumer and other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses at beginning of period	878	1,553	1,242	1,870
Other adjustments	0	0	0	0
Reclassification from allowance for unfunded lending-related commitments	0	0	0	0
Charge-offs	(116)	(250)	(342)	(636)
Recoveries	52	42	139	256
Provision for credit losses	241	(166)	16	(311)
Allowance for loan losses at period end	1,055	1,179	1,055	1,179
Allowance for unfunded lending-related commitments at period end	0	0	0	0
Allowance for credit losses at period end	1,055	1,179	1,055	1,179
Allowance for credit losses at period end, Individually evaluated for impairment	30	53	30	53
Allowance for credit losses at period end, Collectively evaluated for impairment	1,024	1,103	1,024	1,103
Loans at period end, Individually evaluated for impairment	430	870	430	870
Loans at period end, Collectively evaluated for impairment	131,472	148,469	131,472	148,469
Consumer and other | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for credit losses at period end	1	23	1	23
Loans at period end, Loans acquired with deteriorated credit quality	$ 0	$ 0	$ 0	$ 0

Allowance for Loan Losses, Al53

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 (Summary of Activity in the Allowance for Covered Loan Losses) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Allowance for Covered Loan Losses [Roll Forward]
Balance at beginning of period	$ 2,215	$ 1,667	$ 2,131	$ 10,092
Provision for covered loan losses before benefit attributable to FDIC loss share agreements	(1,716)	(818)	(3,339)	(8,703)
Benefit attributable to FDIC loss share agreements	1,373	654	2,671	6,962
Net provision for covered loan losses	(343)	(164)	(668)	(1,741)
Decrease in FDIC indemnification asset	(1,373)	(654)	(2,671)	(6,962)
Loans charged-off	(287)	(293)	(664)	(5,346)
Recoveries of loans charged-off	2,706	2,099	4,790	6,612
Net recoveries (charge-offs)	2,419	1,806	4,126	1,266
Balance at end of period	$ 2,918	$ 2,655	$ 2,918	$ 2,655

Allowance for Loan Losses, Al54

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 (Summary of Impaired Loans, Including Restructured Loans) (Detail) - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Financing Receivable, Impaired [Line Items]
Impaired loans with an allowance for loan loss required	[1]	$ 51,113	$ 69,487	$ 68,471
Impaired loans with no allowance for loan loss required		61,914	57,925	61,066
Total impaired loans	[2]	113,027	127,412	129,537
Allowance for loan losses related to impaired loans		8,483	6,270	6,577
Financing Receivable
Financing Receivable, Impaired [Line Items]
Allowance for loan losses related to impaired loans		3,400
TDRs		$ 59,320	$ 82,275	$ 83,385
[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.

Allowance for Loan Losses, Al55

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 (Summary of Impaired Loans by Loan Class) (Detail) - USD ($) $ in Thousands		9 Months Ended		12 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[1]	$ 51,113	$ 68,471	$ 69,487
Impaired Financing Receivable, Related Allowance		8,483	6,577	6,270
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		61,914	61,066	57,925
Impaired Financing Receivable, Recorded Investment	[2]	113,027	129,537	127,412
Impaired Financing Receivable, Unpaid Principal Balance		132,788	152,473	153,742
Impaired Financing Receivable, Average Recorded Investment		116,642	134,792	134,967
Impaired Financing Receivable, Interest Income Recognized		4,731	5,325	7,190
Commercial | Commercial and industrial
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		8,580	8,384	9,989
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		9,118	11,333	10,785
Impaired Financing Receivable, Related Allowance		1,865	2,273	1,915
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		8,906	9,367	10,784
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		381	537	539
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		9,142	7,563	5,797
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		11,997	8,285	8,862
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		9,716	7,909	6,664
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		539	306	595
Commercial | Franchise
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Commercial | Mortgage warehouse lines of credit
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Commercial | Community Advanatage - homeowners association
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Commercial | Aircraft
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Commercial | Asset-based lending
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		12	25	25
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		1,573	1,952	1,952
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		4	108	87
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		66	75	100
Commercial | Tax exempt
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Commercial | Leases
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Commercial | Other
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Commercial real estate | Residential construction
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		2,023	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		2,023	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		2,023	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		73	0	0
Commercial real estate | Commercial construction
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	425	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	440	0
Impaired Financing Receivable, Related Allowance		0	195	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	432	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	15	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		31	2,803	2,875
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		32	2,803	3,085
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		11	2,777	3,183
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	98	151
Commercial real estate | Land
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		3,559	7,502	5,011
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		7,309	7,502	8,626
Impaired Financing Receivable, Related Allowance		31	40	43
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		3,713	7,572	5,933
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		362	193	544
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		4,114	8,101	10,210
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		4,874	12,432	10,941
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		4,232	8,969	10,268
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		130	538	430
Commercial real estate | Office
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		6,765	8,198	11,038
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		7,724	9,671	12,863
Impaired Financing Receivable, Related Allowance		2,162	322	305
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		7,113	8,493	11,567
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		263	300	576
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		4,171	5,159	4,132
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		5,120	6,359	5,020
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		4,243	6,679	4,445
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		194	244	216
Commercial real estate | Industrial
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		10,049	2,567	195
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		10,542	2,672	277
Impaired Financing Receivable, Related Allowance		1,550	151	15
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		10,662	2,595	214
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		421	92	13
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		2,255	1,903	4,160
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		2,448	2,110	4,498
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		2,304	1,962	3,807
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		141	76	286
Commercial real estate | Retail
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		8,899	10,861	11,045
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		9,596	11,279	14,566
Impaired Financing Receivable, Related Allowance		381	921	487
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		8,906	10,826	12,116
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		306	362	606
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		3,140	8,095	5,487
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		3,302	10,177	7,470
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		3,305	8,647	6,915
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		104	342	330
Commercial real estate | Multi-family
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		1,199	2,822	2,808
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		1,622	3,335	3,321
Impaired Financing Receivable, Related Allowance		203	107	158
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		1,210	2,847	2,839
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		60	109	145
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		1,330	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		1,635	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		1,522	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		50	0	0
Commercial real estate | Mixed use and other
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		7,162	21,172	21,777
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		7,345	21,453	24,076
Impaired Financing Receivable, Related Allowance		1,501	1,738	2,240
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		7,250	20,891	21,483
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		224	656	1,017
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		13,788	9,042	7,985
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		16,576	11,772	8,804
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		14,668	9,467	9,533
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		563	445	449
Home equity
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		547	1,438	1,946
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		762	1,533	2,055
Impaired Financing Receivable, Related Allowance		239	292	475
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		672	1,491	1,995
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		25	42	80
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		7,818	4,484	4,453
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		8,406	6,490	6,172
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		7,065	4,806	4,666
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		229	207	256
Residential real estate
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		4,225	4,889	5,467
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		4,326	4,986	5,600
Impaired Financing Receivable, Related Allowance		521	485	606
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		4,280	4,783	5,399
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		130	157	241
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		13,788	13,234	12,640
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		15,932	14,953	14,334
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		14,387	13,291	12,682
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		449	496	595
Premium finance receivables | Commercial insurance loans
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Premium finance receivables | Life insurance loans
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Premium finance receivables | PCI - life insurance loans
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, Related Allowance		0	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		0	0	0
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		0	0	0
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		0	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		0	0	0
Consumer and other
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		128	213	211
Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance		128	215	213
Impaired Financing Receivable, Related Allowance		30	53	26
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment		139	215	214
Impaired Financing Receivable, with Related Allowance, Interest Income Recognized		6	6	10
Impaired Financing Receivable, with No Related Allowance, Recorded Investment		302	657	161
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance		398	721	222
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment		311	665	173
Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized		$ 15	$ 29	$ 11
[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.

Allowance for Loan Losses, Al56

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 (Summary of the Post-Modification Balance of TDRs) (Detail) $ in Thousands		3 Months Ended				9 Months Ended				12 Months Ended
		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts		Sep. 30, 2015USD ($)contracts	[3],[4]	Sep. 30, 2014USD ($)contracts	[3],[4]
Financing Receivable, Modifications [Line Items]
TDRs, number		1	[1],[2]	3	[1],[2]	10	[1],[2]	16	[1],[2]	15		21
TDRs, Additions | $		$ 222	[1],[2]	$ 667	[1],[2]	$ 1,833	[1],[2]	$ 8,152	[1],[2]	$ 5,648		$ 10,086
Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	1		2		10		10
TDRs, Additions | $	[1]	$ 222		$ 456		$ 1,833		$ 5,671
Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	1		3		5		11
TDRs, Additions | $	[1]	$ 222		$ 667		$ 674		$ 5,774
Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		2		4
TDRs, Additions | $	[1]	$ 0		$ 0		$ 219		$ 2,659
Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Residential real estate and other
Financing Receivable, Modifications [Line Items]
TDRs, number		1	[1],[2]	3	[1],[2]	9	[1],[2]	4	[1],[2]	11		6
TDRs, Additions | $		$ 222	[1],[2]	$ 667	[1],[2]	$ 1,664	[1],[2]	$ 887	[1],[2]	$ 2,613		$ 1,406
Residential real estate and other | Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	1		2		9		3
TDRs, Additions | $	[1]	$ 222		$ 456		$ 1,664		$ 676
Residential real estate and other | Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	1		3		5		3
TDRs, Additions | $	[1]	$ 222		$ 667		$ 674		$ 667
Residential real estate and other | Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		1		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 50		$ 220
Residential real estate and other | Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Commercial and industrial | Commercial
Financing Receivable, Modifications [Line Items]
TDRs, number		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	1		1
TDRs, Additions | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 88	[1],[2]	$ 1,461		$ 88
Commercial and industrial | Commercial | Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 88
Commercial and industrial | Commercial | Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Commercial and industrial | Commercial | Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 88
Commercial and industrial | Commercial | Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Office | Commercial real estate
Financing Receivable, Modifications [Line Items]
TDRs, number		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	1		1
TDRs, Additions | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 790	[1],[2]	$ 720		$ 790
Office | Commercial real estate | Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 790
Office | Commercial real estate | Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Office | Commercial real estate | Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Office | Commercial real estate | Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Industrial | Commercial real estate
Financing Receivable, Modifications [Line Items]
TDRs, number		0	[1],[2]	0	[1],[2]	1	[1],[2]	1	[1],[2]	2		1
TDRs, Additions | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 169	[1],[2]	$ 1,078	[1],[2]	$ 854		$ 1,078
Industrial | Commercial real estate | Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		1		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 169		$ 1,078
Industrial | Commercial real estate | Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Industrial | Commercial real estate | Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		1		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 169		$ 1,078
Industrial | Commercial real estate | Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Retail | Commercial real estate
Financing Receivable, Modifications [Line Items]
TDRs, number		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	0		1
TDRs, Additions | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 202	[1],[2]	$ 0		$ 202
Retail | Commercial real estate | Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 202
Retail | Commercial real estate | Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Retail | Commercial real estate | Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Retail | Commercial real estate | Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Multi-family | Commercial real estate
Financing Receivable, Modifications [Line Items]
TDRs, number		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	0		1
TDRs, Additions | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 181	[1],[2]	$ 0		$ 181
Multi-family | Commercial real estate | Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Multi-family | Commercial real estate | Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 181
Multi-family | Commercial real estate | Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Multi-family | Commercial real estate | Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
Mixed use and other | Commercial real estate
Financing Receivable, Modifications [Line Items]
TDRs, number		0	[1],[2]	0	[1],[2]	0	[1],[2]	7	[1],[2]	0		10
TDRs, Additions | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 4,926	[1],[2]	$ 0		$ 6,341
Mixed use and other | Commercial real estate | Extension at Below Market Terms
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		3
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 2,837
Mixed use and other | Commercial real estate | Reduction of Interest Rate
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		7
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 4,926
Mixed use and other | Commercial real estate | Modification to Interest Only Payments
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		1
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 1,273
Mixed use and other | Commercial real estate | Forgiveness of Debt
Financing Receivable, Modifications [Line Items]
TDRs, number	[1]	0		0		0		0
TDRs, Additions | $	[1]	$ 0		$ 0		$ 0		$ 0
[1]	Balances represent the recorded investment in the loan at the time of the restructuring.
[2]	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.
[3]	Balances represent the recorded investment in the loan at the time of the restructuring.
[4]	Total TDRs represent all loans restructured in TDRs during the previous twelve months from the date indicated.

Allowance for Loan Losses, Al57

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 (Summary of TDRs Subsequent Default Under the Restructured Terms) (Detail) $ in Thousands		3 Months Ended				9 Months Ended				12 Months Ended
		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		1	[1],[2]	3	[1],[2]	10	[1],[2]	16	[1],[2]	15	[3],[4]	21	[3],[4]
Total, Balance | $		$ 222	[1],[2]	$ 667	[1],[2]	$ 1,833	[1],[2]	$ 8,152	[1],[2]	$ 5,648	[3],[4]	$ 10,086	[3],[4]
Subsequent Default, Count	[3],[5]	3		6		4		6
Subsequent Default, Balance | $	[3],[5]	$ 816		$ 2,028		$ 1,030		$ 2,028
Commercial | Commercial and industrial
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	1	[3],[4]	1	[3],[4]
Total, Balance | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 88	[1],[2]	$ 1,461	[3],[4]	$ 88	[3],[4]
Subsequent Default, Count	[3],[5]	0		1		0		1
Subsequent Default, Balance | $	[3],[5]	$ 0		$ 88		$ 0		$ 88
Commercial real estate | Land
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count	[3],[4]									0		0
Total, Balance | $	[3],[4]									$ 0		$ 0
Subsequent Default, Count	[3],[5]	0		0		0		0
Subsequent Default, Balance | $	[3],[5]	$ 0		$ 0		$ 0		$ 0
Commercial real estate | Office
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	1	[3],[4]	1	[3],[4]
Total, Balance | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 790	[1],[2]	$ 720	[3],[4]	$ 790	[3],[4]
Subsequent Default, Count	[3],[5]	0		0		0		0
Subsequent Default, Balance | $	[3],[5]	$ 0		$ 0		$ 0		$ 0
Commercial real estate | Industrial
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		0	[1],[2]	0	[1],[2]	1	[1],[2]	1	[1],[2]	2	[3],[4]	1	[3],[4]
Total, Balance | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 169	[1],[2]	$ 1,078	[1],[2]	$ 854	[3],[4]	$ 1,078	[3],[4]
Subsequent Default, Count	[3],[5]	1		1		1		1
Subsequent Default, Balance | $	[3],[5]	$ 685		$ 1,078		$ 685		$ 1,078
Commercial real estate | Retail
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	0	[3],[4]	1	[3],[4]
Total, Balance | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 202	[1],[2]	$ 0	[3],[4]	$ 202	[3],[4]
Subsequent Default, Count	[3],[5]	0		0		0		0
Subsequent Default, Balance | $	[3],[5]	$ 0		$ 0		$ 0		$ 0
Commercial real estate | Multi-family
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		0	[1],[2]	0	[1],[2]	0	[1],[2]	1	[1],[2]	0	[3],[4]	1	[3],[4]
Total, Balance | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 181	[1],[2]	$ 0	[3],[4]	$ 181	[3],[4]
Subsequent Default, Count	[3],[5]	0		0		0		0
Subsequent Default, Balance | $	[3],[5]	$ 0		$ 0		$ 0		$ 0
Commercial real estate | Mixed use and other
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		0	[1],[2]	0	[1],[2]	0	[1],[2]	7	[1],[2]	0	[3],[4]	10	[3],[4]
Total, Balance | $		$ 0	[1],[2]	$ 0	[1],[2]	$ 0	[1],[2]	$ 4,926	[1],[2]	$ 0	[3],[4]	$ 6,341	[3],[4]
Subsequent Default, Count	[3],[5]	0		2		0		2
Subsequent Default, Balance | $	[3],[5]	$ 0		$ 482		$ 0		$ 482
Residential real estate and other
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Total, Count		1	[1],[2]	3	[1],[2]	9	[1],[2]	4	[1],[2]	11	[3],[4]	6	[3],[4]
Total, Balance | $		$ 222	[1],[2]	$ 667	[1],[2]	$ 1,664	[1],[2]	$ 887	[1],[2]	$ 2,613	[3],[4]	$ 1,406	[3],[4]
Subsequent Default, Count	[3],[5]	2		2		3		2
Subsequent Default, Balance | $	[3],[5]	$ 131		$ 380		$ 345		$ 380
[1]	Balances represent the recorded investment in the loan at the time of the restructuring.
[2]	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.
[3]	Balances represent the recorded investment in the loan at the time of the restructuring.
[4]	Total TDRs represent all loans restructured in TDRs during the previous twelve months from the date indicated.
[5]	TDRs considered to be in payment default are over 30 days past-due subsequent to the restructuring.

Allowance for Loan Losses, Al58

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 (Narrative) (Detail)		3 Months Ended				9 Months Ended				12 Months Ended
		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts		Sep. 30, 2015USD ($)contracts		Sep. 30, 2014USD ($)contracts		Dec. 31, 2014USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
TDRs, number | contracts		1	[1],[2]	3	[1],[2]	10	[1],[2]	16	[1],[2]	15	[3],[4]	21	[3],[4]
Allowance for loan losses related to impaired loans		$ 8,483,000		$ 6,577,000		$ 8,483,000		$ 6,577,000		$ 8,483,000		$ 6,577,000		$ 6,270,000
TDRs, Additions		$ 222,000	[1],[2]	$ 667,000	[1],[2]	$ 1,833,000	[1],[2]	$ 8,152,000	[1],[2]	5,648,000	[3],[4]	10,086,000	[3],[4]
Weighted average extension term		214 months		18 months		49 months		14 months
Weighted average stated interest rate, basis points		3.38%		2.61%		3.58%		1.78%
Weighted average interest only term						28 months		9 months
Loan forgiveness		$ 0		$ 0		$ 0		$ 0
Modification to Interest Only Payments
Financing Receivable, Allowance for Credit Losses [Line Items]
TDRs, number | contracts	[1]	0		0		2		4
TDRs, Additions	[1]	$ 0		$ 0		$ 219,000		$ 2,659,000
Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
TDRs		59,320,000		83,385,000		$ 59,320,000		83,385,000		59,320,000		$ 83,385,000		$ 82,275,000
TDRs, number | contracts						114
Allowance for loan losses related to impaired loans		3,400,000				$ 3,400,000				3,400,000
Interest income, passage of time		98,000		$ 294,000		385,000		$ 529,000
Residential Real Estate | Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Foreclosed residential properties		$ 15,700,000				$ 15,700,000				$ 15,700,000
[1]	Balances represent the recorded investment in the loan at the time of the restructuring.
[2]	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.
[3]	Balances represent the recorded investment in the loan at the time of the restructuring.
[4]	Total TDRs represent all loans restructured in TDRs during the previous twelve months from the date indicated.

Goodwill And Other Intangible59

Goodwill And Other Intangible Assets (Goodwill Assets by Business Segment) (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 405,634
Goodwill Acquired	69,398
Impairment Loss	0
Goodwill Adjustments	(2,866)
Ending balance	472,166
Community banking
Goodwill [Roll Forward]
Beginning balance	331,752
Goodwill Acquired	69,398
Impairment Loss	0
Goodwill Adjustments	0
Ending balance	401,150
Specialty finance
Goodwill [Roll Forward]
Beginning balance	41,768
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	(2,866)
Ending balance	38,902
Wealth management
Goodwill [Roll Forward]
Beginning balance	32,114
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	0
Ending balance	$ 32,114

Goodwill And Other Intangible60

Goodwill And Other Intangible Assets (Summary of Finite-Lived Intangible Assets) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Total other intangible assets, net	$ 25,533	$ 18,811	$ 19,984
Core deposit intangibles | Community banking
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	34,840	29,379	40,438
Accumulated amortization	(16,195)	(17,879)	(27,909)
Net carrying amount	18,645	11,500	12,529
Customer list intangibles | Specialty finance
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,800	1,800	1,800
Accumulated amortization	(1,027)	(941)	(910)
Net carrying amount	773	859	890
Customer list and other intangibles | Wealth management
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	7,940	7,940	7,940
Accumulated amortization	(1,825)	(1,488)	(1,375)
Net carrying amount	$ 6,115	$ 6,452	$ 6,565

Goodwill And Other Intangible61

Goodwill And Other Intangible Assets (Estimated Amortization) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Actual in nine months ended September 30, 2015	$ 1,350	$ 1,202	$ 3,297	$ 3,521
Estimated remaining in 2015	1,325		1,325
Estimated—2016	4,663		4,663
Estimated—2017	3,876		3,876
Estimated—2018	3,371		3,371
Estimated—2019	$ 2,854		$ 2,854

Goodwill And Other Intangible62

Goodwill And Other Intangible Assets (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Indefinite-lived Intangible Assets [Line Items]
Goodwill, Acquired During Period			$ 69,398
Goodwill Adjustments			(2,866)
Amortization of other intangible assets	$ 1,350	$ 1,202	3,297	$ 3,521
Community banking
Indefinite-lived Intangible Assets [Line Items]
Goodwill, Acquired During Period			69,398
Goodwill Adjustments			$ 0
Community banking | Core deposit intangibles
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets			10 years
Specialty finance
Indefinite-lived Intangible Assets [Line Items]
Goodwill, Acquired During Period			$ 0
Goodwill Adjustments			$ (2,866)
Specialty finance | Customer list intangibles
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets			18 years
Wealth management
Indefinite-lived Intangible Assets [Line Items]
Goodwill, Acquired During Period			$ 0
Goodwill Adjustments			$ 0
Wealth management | Customer list intangibles
Indefinite-lived Intangible Assets [Line Items]
Amortization period in years, other intangible assets			10 years

Deposits Deposits (Summary of D

Deposits Deposits (Summary of Deposits) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Balance:
Non-interest bearing	$ 4,705,994	$ 3,518,685	$ 3,253,477
NOW and interest bearing demand deposits	2,231,258	2,236,089	2,086,099
Wealth management deposits	1,469,920	1,226,916	1,212,317
Money market	4,001,518	3,651,467	3,744,682
Savings	1,684,007	1,508,877	1,465,250
Time certificates of deposit	4,135,772	4,139,810	4,303,421
Total deposits	$ 18,228,469	$ 16,281,844	$ 16,065,246
Mix:
Non-interest bearing	26.00%	22.00%	20.00%
NOW and interest bearing demand deposits	12.00%	14.00%	13.00%
Wealth management deposits	8.00%	8.00%	8.00%
Money market	22.00%	22.00%	23.00%
Savings	9.00%	9.00%	9.00%
Time certificates of deposit	23.00%	25.00%	27.00%
Total deposits	100.00%	100.00%	100.00%

Federal Home Loan Bank Advanc64

Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes (Summary of Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Debt Disclosure [Abstract]
Federal Home Loan Bank advances	$ 451,330	$ 733,050	$ 347,500
Other borrowings:
Notes payable	71,250	0	0
Securities sold under repurchase agreements	57,590	48,566	32,530
Other	18,466	18,822	18,953
Secured borrowings	112,672	129,077	0
Total other borrowings	259,978	196,465	51,483
Subordinated notes	140,000	140,000	140,000
Total Federal Home Loan Bank advances, other borrowings and subordinated notes	$ 851,308	$ 1,069,515	$ 538,983

Federal Home Loan Bank Advanc65

Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes (Summary of Pledged Securities Related to Securities Sold Under Repurchase Agreements) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Financial Instruments Owned and Pledged as Collateral [Line Items]
Excess pledged collateral	$ 26,437
Securities sold under repurchase agreements	57,590	$ 48,566	$ 32,530
Securities Sold under Agreements to Repurchase
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments, Not separately reported, Securities for repurchase agreements	84,000
Securities sold under repurchase agreements	57,600	$ 48,600	$ 32,500
Maturity Overnight | U.S. Treasury
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments, Not separately reported, Securities for repurchase agreements	10,003
Maturity Overnight | U.S. Government agencies
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments, Not separately reported, Securities for repurchase agreements	2,867
Maturity Overnight | Municipal
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments, Not separately reported, Securities for repurchase agreements	7,488
Maturity Overnight | Corporate notes, Financial issuers
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments, Not separately reported, Securities for repurchase agreements	15,911
Maturity Overnight | Mortgage-backed securities
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments, Not separately reported, Securities for repurchase agreements	47,758
Maturity Overnight | Securities Sold under Agreements to Repurchase
Financial Instruments Owned and Pledged as Collateral [Line Items]
Pledged financial instruments, Not separately reported, Securities for repurchase agreements	$ 84,027

Federal Home Loan Bank Advanc66

Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes Federal Home Loan Bank Advances, Other Borrowings and Subordinated Notes (Narrative) (Details) - USD ($)	1 Months Ended		3 Months Ended	6 Months Ended	9 Months Ended		12 Months Ended
	Dec. 31, 2014	Dec. 15, 2014	Jun. 30, 2014	Jun. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Nov. 06, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Notes payable	$ 0				$ 71,250,000	$ 0
Loan agreement with unaffiliated banks			$ 101,000,000	$ 101,000,000	150,000,000
Securities sold under repurchase agreements	48,566,000				57,590,000	32,530,000
Fixed rate promissory note	18,822,000				18,466,000	18,953,000
Secured borrowings	129,077,000				112,672,000	0
Subordinated notes	140,000,000				140,000,000	140,000,000
Subordinated debt issued, gross			140,000,000
Proceeds from issuance of subordinated notes, net			139,100,000		$ 0	139,090,000
Loans Payable
Debt Instrument [Line Items]
Debt instrument, Issuance date				Oct. 30, 2009	Dec. 15, 2014
Revolving Credit Facility
Debt Instrument [Line Items]
Notes payable	0				$ 0	0
Maximum borrowing capacity			$ 100,000,000	$ 100,000,000	$ 75,000,000	100,000,000
Maturity date		Dec. 15, 2014			Dec. 14, 2015		Nov. 6, 2014	Oct. 25, 2013
Debt instrument, Frequency of periodic payment					quarterly
Line of credit facility, Unused capacity, Commitment fee percentage					0.20%
Term Facility
Debt Instrument [Line Items]
Notes payable	0				$ 71,300,000
Loan agreement with unaffiliated banks								$ 1,000,000
Maturity date					Jun. 15, 2020			Jun. 1, 2015
Debt instrument, Date of first required payment					Sep. 30, 2015
Debt instrument, Frequency of periodic payment					quarterly
Repayments of debt								$ 1,000,000
Securities Sold under Agreements to Repurchase
Debt Instrument [Line Items]
Securities sold under repurchase agreements	48,600,000				$ 57,600,000	32,500,000
Pledged financial instruments, Not separately reported, Securities for repurchase agreements					$ 84,000,000
Fixed Rate Promissory Note
Debt Instrument [Line Items]
Debt instrument, Issuance date					Aug. 31, 2012
Maturity date					Sep. 1, 2017
Debt instrument, Frequency of periodic payment					monthly
Fixed rate promissory note	18,800,000				$ 18,500,000	$ 19,000,000
Contractual rate					3.75%
Secured Debt
Debt Instrument [Line Items]
Contractual rate					1.3865%
Proceeds from issuance of debt	$ 150,000,000
Subordinated Debt
Debt Instrument [Line Items]
Maturity date					Jun. 13, 2024
Contractual rate					5.00%
Base Rate Loan | Base Rate | Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate					0.50%
Base Rate Loan | Base Rate | Term Facility
Debt Instrument [Line Items]
Basis spread on variable rate					0.75%
Base Rate Loan | Eurodollar Rate
Debt Instrument [Line Items]
Basis spread on variable rate					1.00%
Base Rate Loan | Federal Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate					0.50%
Eurodollar Rate Loan | London Interbank Offered Rate (LIBOR) | Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate					1.50%
Eurodollar Rate Loan | London Interbank Offered Rate (LIBOR) | Term Facility
Debt Instrument [Line Items]
Basis spread on variable rate					1.75%

Junior Subordinated Debenture67

Junior Subordinated Debentures Junior Subordinated Debentures (Summary of Junior Subordinated Debentures) (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Subordinated Borrowing [Line Items]
Junior subordinated debentures	$ 268,566	$ 249,493	$ 249,493
Wintrust Capital Trust III
Subordinated Borrowing [Line Items]
Common Securities	774
Trust Preferred Securities	25,000
Junior subordinated debentures	$ 25,774
Rate Structure	L+3.25
Contractual rate	3.54%
Issue Date	Apr. 30, 2003
Maturity Date	Apr. 30, 2033
Earliest Redemption Date	Apr. 30, 2008
Wintrust Statutory Trust IV
Subordinated Borrowing [Line Items]
Common Securities	$ 619
Trust Preferred Securities	20,000
Junior subordinated debentures	$ 20,619
Rate Structure	L+2.80
Contractual rate	3.13%
Issue Date	Dec. 31, 2003
Maturity Date	Dec. 31, 2033
Earliest Redemption Date	Dec. 31, 2008
Wintrust Statutory Trust V
Subordinated Borrowing [Line Items]
Common Securities	$ 1,238
Trust Preferred Securities	40,000
Junior subordinated debentures	$ 41,238
Rate Structure	L+2.60
Contractual rate	2.93%
Issue Date	May 31, 2004
Maturity Date	May 31, 2034
Earliest Redemption Date	Jun. 30, 2009
Wintrust Capital Trust VII
Subordinated Borrowing [Line Items]
Common Securities	$ 1,550
Trust Preferred Securities	50,000
Junior subordinated debentures	$ 51,550
Rate Structure	L+1.95
Contractual rate	2.29%
Issue Date	Dec. 31, 2004
Maturity Date	Mar. 31, 2035
Earliest Redemption Date	Mar. 31, 2010
Wintrust Capital Trust VIII
Subordinated Borrowing [Line Items]
Common Securities	$ 1,238
Trust Preferred Securities	40,000
Junior subordinated debentures	$ 41,238
Rate Structure	L+1.45
Contractual rate	1.78%
Issue Date	Aug. 31, 2005
Maturity Date	Sep. 30, 2035
Earliest Redemption Date	Sep. 30, 2010
Wintrust Capital Trust IX
Subordinated Borrowing [Line Items]
Common Securities	$ 1,547
Trust Preferred Securities	50,000
Junior subordinated debentures	$ 51,547
Rate Structure	L+1.63
Contractual rate	1.97%
Issue Date	Sep. 30, 2006
Maturity Date	Sep. 30, 2036
Earliest Redemption Date	Sep. 30, 2011
Northview Capital Trust I
Subordinated Borrowing [Line Items]
Common Securities	$ 186
Trust Preferred Securities	6,000
Junior subordinated debentures	$ 6,186
Rate Structure	L+3.00
Contractual rate	3.30%
Issue Date	Aug. 31, 2003
Maturity Date	Nov. 30, 2033
Earliest Redemption Date	Aug. 31, 2008
Town Bankshares Capital Trust I
Subordinated Borrowing [Line Items]
Common Securities	$ 186
Trust Preferred Securities	6,000
Junior subordinated debentures	$ 6,186
Rate Structure	L+3.00
Contractual rate	3.30%
Issue Date	Aug. 31, 2003
Maturity Date	Nov. 30, 2033
Earliest Redemption Date	Aug. 31, 2008
First Northwest Capital Trust I
Subordinated Borrowing [Line Items]
Common Securities	$ 155
Trust Preferred Securities	5,000
Junior subordinated debentures	$ 5,155
Rate Structure	L+3.00
Contractual rate	3.33%
Issue Date	May 31, 2004
Maturity Date	May 31, 2034
Earliest Redemption Date	May 31, 2009
Suburban Illinois Capital Trust II
Subordinated Borrowing [Line Items]
Common Securities	$ 464
Trust Preferred Securities	15,000
Junior subordinated debentures	$ 15,464
Rate Structure	L+1.75
Contractual rate	2.09%
Issue Date	Dec. 31, 2006
Maturity Date	Dec. 31, 2036
Earliest Redemption Date	Dec. 31, 2011
Community Financial Shares Statutory Trust II
Subordinated Borrowing [Line Items]
Common Securities	$ 109
Trust Preferred Securities	3,500
Junior subordinated debentures	$ 3,609
Rate Structure	L+1.62
Contractual rate	1.96%
Issue Date	Jun. 30, 2007
Maturity Date	Sep. 30, 2037
Earliest Redemption Date	Jun. 30, 2012
Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Debt, weighted average interest rate	2.48%
London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust III
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	3.25%
London Interbank Offered Rate (LIBOR) | Wintrust Statutory Trust IV
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	2.80%
London Interbank Offered Rate (LIBOR) | Wintrust Statutory Trust V
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	2.60%
London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust VII
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	1.95%
London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust VIII
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	1.45%
London Interbank Offered Rate (LIBOR) | Wintrust Capital Trust IX
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	1.63%
London Interbank Offered Rate (LIBOR) | Northview Capital Trust I
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	3.00%
London Interbank Offered Rate (LIBOR) | Town Bankshares Capital Trust I
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	3.00%
London Interbank Offered Rate (LIBOR) | First Northwest Capital Trust I
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	3.00%
London Interbank Offered Rate (LIBOR) | Suburban Illinois Capital Trust II
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	1.75%
London Interbank Offered Rate (LIBOR) | Community Financial Shares Statutory Trust II
Subordinated Borrowing [Line Items]
Rate Structure, Incremental interest rate over base rate	1.62%

Junior Subordinated Debenture68

Junior Subordinated Debentures (Narrative) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Subordinated Borrowing [Line Items]
Percentage ownership interest in subsidiary trusts	100.00%
Number of unconsolidated subsidiary trusts	11
Common securities, approximate percentage of junior subordinated debentures	3.00%
Trust preferred securities, approximate percentage of junior subordinated debentures	97.00%
Junior subordinated debentures	$ 268,566	$ 249,493	$ 249,493
Consecutive quarters of deferred payment	20
Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Debt, weighted average interest rate	2.48%
Debt, Hedge Adjusted Weighted Average Interest Rate	3.13%
Tier One Risk Based Capital	$ 65,100
Tier Two Risk Based Capital	195,400
Cash Flow Hedge of Junior Subordinated Debentures | Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Swaps and Caps
Subordinated Borrowing [Line Items]
Notional amount	$ 225,000

Segment Information (Summary of

Segment Information (Summary of Segment Information) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income	$ 165,540	$ 151,670	$ 474,323	$ 444,856
Net interest income, Change in Contribution	$ 13,870		$ 29,467
Net interest income, Change in Contribution Percentage	9.00%		7.00%
Non-interest income	$ 64,953	57,952	$ 206,507	157,583
Non-interest income, Change in Contribution	$ 7,001		$ 48,924
Non-interest income, Change in Contribution Percentage	12.00%		31.00%
Net revenue	$ 230,493	209,622	$ 680,830	602,439
Net revenue, Change in Contribution	$ 20,871		$ 78,391
Net revenue, Change in Contribution Percentage	10.00%		13.00%
Segment profit	$ 38,355	40,224	$ 121,238	113,265
Segment profit, Change in Contribution	$ (1,869)		$ 7,973
Segment profit, Change in Contribution Percentage	(5.00%)		7.00%
Segment assets	$ 22,043,930	19,169,345	$ 22,043,930	19,169,345	$ 20,010,727
Segment assets, Change in Contribution	$ 2,874,585
Segment assets, Change in Contribution Percentage	15.00%
Operating Segments
Segment Reporting Information [Line Items]
Net interest income	$ 161,567	147,778	462,065	432,870
Net interest income, Change in Contribution	$ 13,789		$ 29,195
Net interest income, Change in Contribution Percentage	9.00%		7.00%
Non-interest income	$ 72,200	64,785	$ 228,112	177,953
Non-interest income, Change in Contribution	$ 7,415		$ 50,159
Non-interest income, Change in Contribution Percentage	11.00%		28.00%
Net revenue	$ 233,767	212,563	$ 690,177	610,823
Net revenue, Change in Contribution	$ 21,204		$ 79,354
Net revenue, Change in Contribution Percentage	10.00%		13.00%
Operating Segments | Community banking
Segment Reporting Information [Line Items]
Net interest income	$ 132,542	121,998	$ 382,187	359,981
Net interest income, Change in Contribution	$ 10,544		$ 22,206
Net interest income, Change in Contribution Percentage	9.00%		6.00%
Non-interest income	$ 45,574	38,274	$ 146,739	98,930
Non-interest income, Change in Contribution	$ 7,300		$ 47,809
Non-interest income, Change in Contribution Percentage	19.00%		48.00%
Net revenue	$ 178,116	160,272	$ 528,926	458,911
Net revenue, Change in Contribution	$ 17,844		$ 70,015
Net revenue, Change in Contribution Percentage	11.00%		15.00%
Segment profit	$ 22,723	26,184	$ 76,821	73,393
Segment profit, Change in Contribution	$ (3,461)		$ 3,428
Segment profit, Change in Contribution Percentage	(13.00%)		5.00%
Segment assets	$ 18,505,830	15,945,744	$ 18,505,830	15,945,744
Segment assets, Change in Contribution	$ 2,560,086
Segment assets, Change in Contribution Percentage	16.00%
Operating Segments | Specialty finance
Segment Reporting Information [Line Items]
Net interest income	$ 24,657	21,903	67,041	60,907
Net interest income, Change in Contribution	$ 2,754		$ 6,134
Net interest income, Change in Contribution Percentage	13.00%		10.00%
Non-interest income	$ 8,264	8,320	$ 25,270	24,656
Non-interest income, Change in Contribution	$ (56)		$ 614
Non-interest income, Change in Contribution Percentage	(1.00%)		2.00%
Net revenue	$ 32,921	30,223	$ 92,311	85,563
Net revenue, Change in Contribution	$ 2,698		$ 6,748
Net revenue, Change in Contribution Percentage	9.00%		8.00%
Segment profit	$ 12,545	10,973	$ 34,875	30,257
Segment profit, Change in Contribution	$ 1,572		$ 4,618
Segment profit, Change in Contribution Percentage	14.00%		15.00%
Segment assets	$ 2,987,236	2,704,591	$ 2,987,236	2,704,591
Segment assets, Change in Contribution	$ 282,645
Segment assets, Change in Contribution Percentage	10.00%
Operating Segments | Wealth management
Segment Reporting Information [Line Items]
Net interest income	$ 4,368	3,877	12,837	11,982
Net interest income, Change in Contribution	$ 491		$ 855
Net interest income, Change in Contribution Percentage	13.00%		7.00%
Non-interest income	$ 18,362	18,191	$ 56,103	54,367
Non-interest income, Change in Contribution	$ 171		$ 1,736
Non-interest income, Change in Contribution Percentage	1.00%		3.00%
Net revenue	$ 22,730	22,068	$ 68,940	66,349
Net revenue, Change in Contribution	$ 662		$ 2,591
Net revenue, Change in Contribution Percentage	3.00%		4.00%
Segment profit	$ 3,087	3,067	$ 9,542	9,615
Segment profit, Change in Contribution	$ 20		$ (73)
Segment profit, Change in Contribution Percentage	1.00%		(1.00%)
Segment assets	$ 550,864	519,010	$ 550,864	519,010
Segment assets, Change in Contribution	$ 31,854
Segment assets, Change in Contribution Percentage	6.00%
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net interest income	$ 3,973	3,892	12,258	11,986
Net interest income, Change in Contribution	$ 81		$ 272
Net interest income, Change in Contribution Percentage	2.00%		2.00%
Non-interest income	$ (7,247)	(6,833)	$ (21,605)	(20,370)
Non-interest income, Change in Contribution	$ (414)		$ (1,235)
Non-interest income, Change in Contribution Percentage	(6.00%)		(6.00%)
Net revenue	$ (3,274)	$ (2,941)	$ (9,347)	$ (8,384)
Net revenue, Change in Contribution	$ (333)		$ (963)
Net revenue, Change in Contribution Percentage	(11.00%)		(11.00%)

Segment Information Segment Inf

Segment Information Segment Information (Narrative) (Detail)	9 Months Ended
	Sep. 30, 2015segment
Segment Reporting Information [Line Items]
Number of reportable segments	3
Number Of Subsidiaries	15
Community banking
Segment Reporting Information [Line Items]
Number of reportable segments	1

Derivative Financial Instrume71

Derivative Financial Instruments Derivative Financial Instruments (Interest Rate Cap Derivative Summary) (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Interest Rate Cap Two Hundred Fifteen Million Notional May Two Thousand Sixteen Maturity | Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	May 3, 2016
Notional amount	$ 215,000
Fair Value as of End of Period	$ 0
Interest Rate Cap Fifty Six Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity | Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Aug. 22, 2016
Notional amount	$ 56,500
Fair Value as of End of Period	$ 2
Interest Rate Cap One Hundred Million Notional March Two Thousand Seventeen Maturity | Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Mar. 21, 2017
Notional amount	$ 100,000
Fair Value as of End of Period	$ 69
Interest Rate Cap Seventy Five Million Notional November Two Thousand Sixteen Maturity | Not Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Nov. 16, 2016
Notional amount	$ 75,000
Fair Value as of End of Period	13
Total Interest Rate Cap
Interest Rate Cap Derivative Summary [Line Items]
Notional amount	796,500
Fair Value as of End of Period	$ 300
Cash Flow Hedging | Interest Rate Cap Two Hundred Sixteen Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity | Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Aug. 29, 2016
Notional amount	$ 216,500
Fair Value as of End of Period	$ 5
Cash Flow Hedging | Interest Rate Cap Forty Three Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity | Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Aug. 22, 2016
Notional amount	$ 43,500
Fair Value as of End of Period	$ 2
Cash Flow Hedging | Interest Rate Cap Fifty Million Notional September Two Thousand Seventeen Maturity | Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Sep. 15, 2017
Notional amount	$ 50,000
Fair Value as of End of Period	$ 112
Cash Flow Hedging | Interest Rate Cap Forty Million Notional September Two Thousand Seventeen Maturity | Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Derivative, maturity date	Sep. 30, 2017
Notional amount	$ 40,000
Fair Value as of End of Period	97
Cash Flow Hedging | Total Interest Rate Cap | Designated as Hedging Instrument
Interest Rate Cap Derivative Summary [Line Items]
Notional amount	350,000
Fair Value as of End of Period	$ 216

Derivative Financial Instrume72

Derivative Financial Instruments Derivative Financial Instruments (Schedule Of Fair Value Of Derivative Financial Instruments) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	$ 56,938	$ 37,841	$ 33,275
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	57,429	36,921	31,451
Other Assets
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	69,034	47,964	43,343
Other Assets | Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	221	1,442	2,026
Other Assets | Designated as Hedging Instrument | Interest Rate Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	216	1,390	1,947
Other Assets | Designated as Hedging Instrument | Interest Rate Contract | Fair Value Hedging
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	5	52	79
Other Assets | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	68,813	46,522	41,317
Other Assets | Not Designated as Hedging Instrument | Interest Rate Contract
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	56,717	36,399	31,249
Other Assets | Not Designated as Hedging Instrument | Interest Rate Lock Commitments
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	11,836	10,028	10,010
Other Assets | Not Designated as Hedging Instrument | Forward Commitments to Sell Mortgage Loans
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	0	23	41
Other Assets | Not Designated as Hedging Instrument | Foreign Exchange Contract
Derivative [Line Items]
Derivative Assets, Fair Value, Amount not Offset Against Collateral	260	72	17
Other Liabilities
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	65,198	41,180	35,505
Other Liabilities | Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	1,620	1,994	2,202
Other Liabilities | Designated as Hedging Instrument | Interest Rate Contract | Cash Flow Hedging
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	1,329	1,994	2,202
Other Liabilities | Designated as Hedging Instrument | Interest Rate Contract | Fair Value Hedging
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	291	0	0
Other Liabilities | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	63,578	39,186	33,303
Other Liabilities | Not Designated as Hedging Instrument | Interest Rate Contract
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	55,809	34,927	29,249
Other Liabilities | Not Designated as Hedging Instrument | Interest Rate Lock Commitments
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	0	20	31
Other Liabilities | Not Designated as Hedging Instrument | Forward Commitments to Sell Mortgage Loans
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	7,713	4,239	3,986
Other Liabilities | Not Designated as Hedging Instrument | Foreign Exchange Contract
Derivative [Line Items]
Derivative Liabilities, Fair Value, Amount Not Offset Against Collateral	$ 56	$ 0	$ 37

Derivative Financial Instrume73

Derivative Financial Instruments Derivative Financial Instruments (Schedule Of Cash Flow Hedging Instruments) (Detail) $ in Thousands	Sep. 30, 2015USD ($)
Total Interest Rate Cap
Derivative [Line Items]
Notional amount	$ 796,500
Fair Value Asset (Liability)	300
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Swap Fifty Million Notional September Two Thousand Sixteen Maturity
Derivative [Line Items]
Notional amount	50,000
Fair Value Asset (Liability)	(862)
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Swap Twenty Five Million Notional October Two Thousand Sixteen Maturity
Derivative [Line Items]
Notional amount	25,000
Fair Value Asset (Liability)	(467)
Cash Flow Hedging | Designated as Hedging Instrument | Total Interest Rate Swap
Derivative [Line Items]
Notional amount	75,000
Fair Value Asset (Liability)	(1,329)
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Cap Forty Three Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity
Derivative [Line Items]
Notional amount	43,500
Fair Value Asset (Liability)	2
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Cap Two Hundred Sixteen Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity
Derivative [Line Items]
Notional amount	216,500
Fair Value Asset (Liability)	5
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Cap Fifty Million Notional September Two Thousand Seventeen Maturity
Derivative [Line Items]
Notional amount	50,000
Fair Value Asset (Liability)	112
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Cap Forty Million Notional September Two Thousand Seventeen Maturity
Derivative [Line Items]
Notional amount	40,000
Fair Value Asset (Liability)	97
Cash Flow Hedging | Designated as Hedging Instrument | Total Interest Rate Cap
Derivative [Line Items]
Notional amount	350,000
Fair Value Asset (Liability)	216
Cash Flow Hedging | Designated as Hedging Instrument | Interest Rate Swaps and Caps
Derivative [Line Items]
Notional amount	425,000
Fair Value Asset (Liability)	$ (1,113)

Derivative Financial Instrume74

Derivative Financial Instruments Derivative Financial Instruments (Rollforward Of Amounts In Accumulated Other Comprehensive Income Related To Interest Rate Swaps Designated As Cash Flow Hedges) (Detail) - Interest Rate Contract - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Rollforward of AOCI from Cash Flow Hedging Derivatives [Roll Forward]
Unrealized loss at beginning of period	$ (4,408)	$ (4,695)	$ (4,062)	$ (3,971)
Amount reclassified from accumulated other comprehensive income to interest expense on deposits and junior subordinated debentures	571	553	1,460	1,567
Amount of loss recognized in other comprehensive income	(503)	418	(1,738)	(1,320)
Unrealized loss at end of period	$ (4,340)	$ (3,724)	$ (4,340)	$ (3,724)

Derivative Financial Instrume75

Derivative Financial Instruments Derivative Financial Instruments (Derivatives Used To Hedge Changes In Fair Value Attributable To Interest Rate Risk) (Detail) - Fair Value Hedging - Designated as Hedging Instrument - Interest Rate Contract - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Derivative [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	$ (323)	$ 16	$ (338)	$ (27)
Amount of Gain or (Loss) Recognized in Income on Hedged Item	302	(16)	315	24
Income Statement Gain/(Loss) due to Hedge Ineffectiveness	$ (21)	$ 0	$ (23)	$ (3)

Derivative Financial Instrume76

Derivative Financial Instruments Derivative Financial Instruments (Summary Amounts Included In Consolidated Statement Of Income Related To Derivatives) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Interest Rate Swaps and Caps | Trading (losses) gains, net
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ (275)	$ 270	$ (592)	$ (1,144)
Mortgage Banking Derivatives | Mortgage banking revenue
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(4,062)	(562)	(1,669)	(1,770)
Covered Call Options | Fees from covered call options
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	2,810	2,107	11,735	4,893
Foreign Exchange Contract | Trading (losses) gains, net
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 113	$ (12)	$ 133	$ (23)

Derivative Financial Instrume77

Derivative Financial Instruments Derivative Financial Instruments (Derivative Asset and Liability Balance Sheet Offsetting) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014		Sep. 30, 2014
Derivative Assets
Gross Amounts Recognized	$ 56,938	$ 37,841		$ 33,275
Less: Amounts offset in the Statements of Financial Condition	0	0		0
Net amount presented in the Statements of Financial Condition	56,938	37,841		33,275
Offsetting Derivative Positions	(614)	(2,771)		(5,417)
Collateral Posted	0	0		0
Net Credit Exposure	56,324	35,070		27,858
Derivative Liabilities
Gross Amounts Recognized	57,429	36,921		31,451
Less: Amounts offset in the Statements of Financial Condition	0	0		0
Net amount presented in the Statements of Financial Condition	57,429	36,921		31,451
Offsetting Derivative Positions	(614)	(2,771)		(5,417)
Collateral Posted	(54,410)	(34,150)	[1]	(26,034)	[1]
Net Credit Exposure	$ 2,405	0		0
Security Owned and Pledged as Collateral, Fair Value		$ 43,800		$ 33,900
[1]	As of December 31, 2014 and September 30, 2014, the Company posted collateral of $43.8 million and $33.9 million, respectively, which resulted in excess collateral with its counterparties. For purposes of this disclosure, the amount of posted collateral is limited to the amount offsetting the derivative liability.

Derivative Financial Instrume78

Derivative Financial Instruments Derivative Financial Instruments (Narrative) (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2015USD ($)contractsderivative_instruments	Sep. 30, 2014USD ($)derivative_instruments	Sep. 30, 2015USD ($)contractsderivative_instruments	Sep. 30, 2014USD ($)derivative_instruments	Dec. 31, 2014derivative_instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive income to interest expense in the next twelve months			$ 3,100,000
Basis Amortization of Hedged item no longer in a Hedging Relationship	$ 43,000	$ 43,000	129,000	$ 129,000
Derivative, Net Liability Position, Aggregate Fair Value	$ 58,500,000		$ 58,500,000
Interest Rate Cap | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of Interest Rate Derivatives Held | contracts	4		4
Notional amount	$ 446,500,000		$ 446,500,000
Interest Rate Contract | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	3,300,000,000		3,300,000,000
Forward Commitments to Sell Mortgage Loans | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	731,100,000		731,100,000
Interest Rate Lock Commitments | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	455,700,000		455,700,000
Foreign Exchange Contract | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 16,300,000		$ 16,300,000
Covered Call Options | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Number of Instruments Held | derivative_instruments	0	0	0	0	0
Minimum | Interest Rate Contract | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, maturity date			Oct. 31, 2015
Maximum | Interest Rate Contract | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, maturity date			Feb. 28, 2045
Cash Flow Hedging | Interest Rate Contract | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net			$ 0	$ 0
Fair Value Hedging | Interest Rate Swap | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of Interest Rate Derivatives Held | derivative_instruments	4		4
Notional amount	$ 16,700,000		$ 16,700,000
Fair Value Hedging | Interest Rate Contract | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Income Statement Gain/(Loss) due to Hedge Ineffectiveness	$ (21,000)	$ 0	$ (23,000)	$ (3,000)
Cash flow hedge of variable rate deposits | Cash Flow Hedging | Interest Rate Cap | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of Interest Rate Derivatives Held | derivative_instruments	2		2
Interest Rate Cap Two Hundred Sixteen Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity | Cash Flow Hedging | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 216,500,000		$ 216,500,000
Derivative, maturity date			Aug. 29, 2016
Interest Rate Cap Forty Three Million Five Hundred Thousand Notional August Two Thousand Sixteen Maturity | Cash Flow Hedging | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 43,500,000		$ 43,500,000
Derivative, maturity date			Aug. 22, 2016
Cash Flow Hedge of Junior Subordinated Debentures | Cash Flow Hedging | Interest Rate Cap | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of Interest Rate Derivatives Held | derivative_instruments	2		2
Cash Flow Hedge of Junior Subordinated Debentures | Cash Flow Hedging | Interest Rate Swap | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Number of Interest Rate Derivatives Held | derivative_instruments	2		2
De-designated Hedge | Interest Rate Cap | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	$ 96,500,000		$ 96,500,000

Fair Values Of Assets And Lia79

Fair Values Of Assets And Liabilities (Summary Of Balances Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	$ 2,214,281	$ 1,792,078	$ 1,782,648
Trading account securities	3,312	1,206	6,015
Mortgage loans held-for-sale, at fair value	347,005	351,290	363,303
Derivative assets	56,938	37,841	33,275
Derivative liabilities	57,429	36,921	31,451
U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	285,922	381,805	378,261
U.S. Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	645,023	668,316	739,752
Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	297,342	238,529	187,103
Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	815,045	318,710	291,222
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	54,004	51,139	52,155
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities	3,312	1,206	6,015
Mortgage loans held-for-sale, at fair value	347,005	351,290	363,303
Mortgage servicing rights	7,875	8,435	8,137
Nonqualified deferred compensation assets	8,342	7,951	7,927
Derivative assets		47,964	43,343
Total	2,649,849	2,208,924	2,211,373
Derivative liabilities		41,180	35,505
Fair Value, Measurements, Recurring | U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	285,922	381,805	378,261
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, at fair value	645,023	668,316	739,752
Fair Value, Measurements, Recurring | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	297,342	238,529	187,103
Fair Value, Measurements, Recurring | Corporate notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	116,945	133,579	134,155
Fair Value, Measurements, Recurring | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	815,045	318,710	291,222
Fair Value, Measurements, Recurring | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	54,004	51,139	52,155
Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities	3,312	1,206	6,015
Mortgage loans held-for-sale, at fair value	347,005	351,290	363,303
Mortgage servicing rights	0	0	0
Nonqualified deferred compensation assets	8,342	7,951	7,927
Derivative assets	69,034	47,964	43,343
Total	2,549,057	2,117,825	2,129,038
Derivative liabilities	65,198	41,180	35,505
Fair Value, Measurements, Recurring | Level 2 | U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	285,922	381,805	378,261
Fair Value, Measurements, Recurring | Level 2 | U.S. Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	645,023	668,316	739,752
Fair Value, Measurements, Recurring | Level 2 | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	228,941	179,576	136,866
Fair Value, Measurements, Recurring | Level 2 | Corporate notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	116,945	133,579	134,155
Fair Value, Measurements, Recurring | Level 2 | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	815,045	318,710	291,222
Fair Value, Measurements, Recurring | Level 2 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	29,488	27,428	28,194
Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities	0	0	0
Mortgage loans held-for-sale, at fair value	0	0	0
Mortgage servicing rights	7,875	8,435	8,137
Nonqualified deferred compensation assets	0	0	0
Derivative assets	0	0	0
Total	100,792	91,099	82,335
Derivative liabilities	0	0	0
Fair Value, Measurements, Recurring | Level 3 | U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0	0
Fair Value, Measurements, Recurring | Level 3 | U.S. Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0	0
Fair Value, Measurements, Recurring | Level 3 | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	68,401	58,953	50,237
Fair Value, Measurements, Recurring | Level 3 | Corporate notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0	0
Fair Value, Measurements, Recurring | Level 3 | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	0	0	0
Fair Value, Measurements, Recurring | Level 3 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value	$ 24,516	$ 23,711	$ 23,961

Fair Values Of Assets And Lia80

Fair Values Of Assets And Liabilities (Summary Of Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance		$ 8,034	$ 8,227	$ 8,435	$ 8,946
Total net gains (losses) included in Net income	[1]	(159)	(90)	(560)	(809)
Net transfers into/(out of) Level 3	[2]		0
Ending Balance		7,875	8,137	7,875	8,137
Municipal
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance		58,572	38,053	58,953	36,386
Total net gains (losses) included in Other comprehensive income		223	(27)	(287)	193
Purchases		10,405	4,129	21,254	9,095
Settlements		(799)	(800)	(11,519)	(4,319)
Net transfers into/(out of) Level 3	[2]		8,882		8,882
Ending Balance		68,401	50,237	68,401	50,237
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance		24,996	24,152	23,711	22,163
Total net gains (losses) included in Other comprehensive income		(480)	(191)	805	1,798
Net transfers into/(out of) Level 3	[2]		0
Ending Balance		$ 24,516	$ 23,961	$ 24,516	$ 23,961
[1]	Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income.
[2]	Transfers into Level 3 relate to a reclassification of municipal bonds in the current quarter.

Fair Values Of Assets And Lia81

Fair Values Of Assets And Liabilities (Summary Of Assets Measured At Fair Value On A Nonrecurring Basis) (Detail) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
		Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans—collateral based	[1]	$ 113,027	$ 113,027	$ 127,412	$ 129,537
Fair Value Losses Recognized, Impaired loans—collateral based		5,262	11,517
Fair Value Losses Recognized, Other real estate owned	[2]	989	4,834
Fair Value Losses Recognized, Total		6,251	16,351
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans—collateral based		73,819	73,819
Other real estate owned	[2]	80,524	80,524
Total		154,343	154,343
Fair Value, Measurements, Nonrecurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans—collateral based		0	0
Other real estate owned	[2]	0	0
Total		0	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	0
Other real estate owned	[2]	0	0
Total		0	0
Fair Value, Measurements, Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans—collateral based		73,819	73,819
Other real estate owned		80,524	80,524
Total		$ 154,343	$ 154,343
[1]	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.
[2]	Fair value losses recognized, net on other real estate owned include valuation adjustments and charge-offs during the respective period.

Fair Values Of Assets and Lia82

Fair Values Of Assets and Liabilities (Schedule Of Valuation Techniques And Significant Unobservable Inputs Used To Measure Both Recurring And Non-Recurring) (Detail) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
		Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Available-for-sale securities, at fair value		$ 2,214,281	$ 2,214,281	$ 1,792,078	$ 1,782,648
Impaired loans—collateral based	[1]	$ 113,027	113,027	127,412	129,537
Other Real Estate Owned
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
Municipal
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Available-for-sale securities, at fair value		$ 297,342	297,342	238,529	187,103
Equity securities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Available-for-sale securities, at fair value		54,004	54,004	51,139	52,155
Fair Value, Measurements, Recurring
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Mortgage servicing rights		7,875	7,875	8,435	8,137
Fair Value, Measurements, Recurring | Municipal
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Available-for-sale securities, at fair value		297,342	297,342	238,529	187,103
Fair Value, Measurements, Recurring | Equity securities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Available-for-sale securities, at fair value		54,004	54,004	51,139	52,155
Fair Value, Measurements, Nonrecurring
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Impaired loans—collateral based		73,819	73,819
Other real estate owned	[2]	80,524	80,524
Level 3 | Fair Value, Measurements, Recurring
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Mortgage servicing rights		$ 7,875	7,875	8,435	8,137
Level 3 | Fair Value, Measurements, Recurring | Mortgage Servicing Rights
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Valuation Methodology		Discounted cash flows
Level 3 | Fair Value, Measurements, Recurring | Mortgage Servicing Rights | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount Rate		9.00%
Fair Value Inputs, Prepayment Rate		9.00%
Level 3 | Fair Value, Measurements, Recurring | Mortgage Servicing Rights | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount Rate		13.00%
Fair Value Inputs, Prepayment Rate		29.00%
Level 3 | Fair Value, Measurements, Recurring | Mortgage Servicing Rights Discount Rate Input
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Input		Discount rate
Range of Inputs		9%-13%
Weighted Average of Inputs		9.15%
Impact to valuation from an increased or higher input value		Decrease
Level 3 | Fair Value, Measurements, Recurring | Mortgage Servicing Rights Prepayment Rate Input
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Significant Unobservable Input		Constant prepayment rate (CPR)
Range of Inputs		9%-29%
Weighted Average of Inputs		12.93%
Impact to valuation from an increased or higher input value		Decrease
Level 3 | Fair Value, Measurements, Recurring | Municipal
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Available-for-sale securities, at fair value		$ 68,401	68,401	58,953	50,237
Valuation Methodology		Bond pricing
Significant Unobservable Input		Equivalent rating
Range of Inputs		BBB-AA+
Impact to valuation from an increased or higher input value		Increase
Level 3 | Fair Value, Measurements, Recurring | Equity securities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Available-for-sale securities, at fair value		$ 24,516	$ 24,516	$ 23,711	$ 23,961
Valuation Methodology		Discounted cash flows
Significant Unobservable Input		Discount rate
Range of Inputs		2.01%-2.43%
Weighted Average of Inputs		2.22%
Impact to valuation from an increased or higher input value		Decrease
Level 3 | Fair Value, Measurements, Recurring | Equity securities | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount Rate		2.01%
Level 3 | Fair Value, Measurements, Recurring | Equity securities | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount Rate		2.43%	2.43%
Level 3 | Fair Value, Measurements, Nonrecurring
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Impaired loans—collateral based		$ 73,819	$ 73,819
Other real estate owned		$ 80,524	$ 80,524
Level 3 | Fair Value, Measurements, Nonrecurring | Impaired Loans
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Valuation Methodology		Appraisal value
Significant Unobservable Input		Appraisal adjustment - cost of sale
Range of Inputs		10%
Weighted Average of Inputs		10.00%
Impact to valuation from an increased or higher input value		Decrease
Level 3 | Fair Value, Measurements, Nonrecurring | Impaired Loans | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
Level 3 | Fair Value, Measurements, Nonrecurring | Impaired Loans | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
Level 3 | Fair Value, Measurements, Nonrecurring | Other Real Estate Owned
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Valuation Methodology		Appraisal value
Significant Unobservable Input		Appraisal adjustment - cost of sale
Range of Inputs		10%
Weighted Average of Inputs		10.00%
Impact to valuation from an increased or higher input value		Decrease
Level 3 | Fair Value, Measurements, Nonrecurring | Other Real Estate Owned | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
Level 3 | Fair Value, Measurements, Nonrecurring | Other Real Estate Owned | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
[1]	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.
[2]	Fair value losses recognized, net on other real estate owned include valuation adjustments and charge-offs during the respective period.

Fair Values Of Assets And Lia83

Fair Values Of Assets And Liabilities (Summary Of Carrying Amounts And Estimated Fair Values Of Financial Instruments) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest bearing deposits with banks	$ 701,106		$ 998,437	$ 620,370
Available-for-sale securities, at fair value	2,214,281		1,792,078	1,782,648
Trading account securities	3,312		1,206	6,015
Federal Home Loan Bank and Federal Reserve Bank stock, at cost	90,308		91,582	80,951
Brokerage customer receivables	28,293		24,221	26,624
Mortgage loans held-for-sale, at fair value	347,005		351,290	363,303
Derivative assets	56,324		35,070	27,858
FDIC indemnification asset	0	$ 3,429	11,846	27,359	$ 46,115	$ 85,672
Accrued interest receivable and other	667,036		501,882	494,213
Federal Home Loan Bank advances	451,330		733,050	347,500
Other borrowings	259,978		196,465	51,483
Subordinated notes	140,000		140,000	140,000
Junior subordinated debentures	268,566		249,493	249,493
Derivative liabilities	57,429		36,921	31,451
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	250,655		230,707	287,416
Interest bearing deposits with banks	701,106		998,437	620,370
Available-for-sale securities, at fair value	2,214,281		1,792,078	1,782,648
Trading account securities	3,312		1,206	6,015
Federal Home Loan Bank and Federal Reserve Bank stock, at cost	90,308		91,582	80,951
Brokerage customer receivables	28,293		24,221	26,624
Mortgage loans held-for-sale, at fair value	347,005		351,290	363,303
Total loans	16,484,820		14,636,107	14,306,664
Mortgage servicing rights	7,875		8,435	8,137
Nonqualified deferred compensation assets	8,342		7,951	7,927
Derivative assets	69,034		47,964	43,343
FDIC indemnification asset	0		11,846	27,359
Accrued interest receivable and other	192,572		169,156	170,517
Total financial assets	20,397,603		18,370,980	17,731,274
Non-maturity deposits	14,092,697		12,142,034	11,761,825
Deposits with stated maturities	4,135,772		4,139,810	4,303,421
Federal Home Loan Bank advances	451,330		733,050	347,500
Other borrowings	259,978		196,465	51,483
Subordinated notes	140,000		140,000	140,000
Junior subordinated debentures	268,566		249,493	249,493
Derivative liabilities	65,198		41,180	35,505
Accrued interest payable	11,364		8,001	8,995
Total financial liabilities	19,424,905		17,650,033	16,898,222
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	250,655		230,707	287,416
Interest bearing deposits with banks	701,106		998,437	620,370
Available-for-sale securities, at fair value	2,214,281		1,792,078	1,782,648
Trading account securities	3,312		1,206	6,015
Federal Home Loan Bank and Federal Reserve Bank stock, at cost	90,308		91,582	80,951
Brokerage customer receivables	28,293		24,221	26,624
Mortgage loans held-for-sale, at fair value	347,005		351,290	363,303
Total loans	17,284,375		15,346,266	15,001,394
Mortgage servicing rights	7,875		8,435	8,137
Nonqualified deferred compensation assets	8,342		7,951	7,927
Derivative assets	69,034		47,964	43,343
FDIC indemnification asset	0		11,846	27,359
Accrued interest receivable and other	192,572		169,156	170,517
Total financial assets	21,197,158		19,081,139	18,426,004
Non-maturity deposits	14,092,697		12,142,034	11,761,825
Deposits with stated maturities	4,137,856		4,143,161	4,303,717
Federal Home Loan Bank advances	459,154		738,113	352,516
Other borrowings	259,978		197,883	51,483
Subordinated notes	142,953		143,639	142,720
Junior subordinated debentures	268,058		250,305	250,452
Derivative liabilities	65,198		41,180	35,505
Accrued interest payable	11,364		8,001	8,995
Total financial liabilities	$ 19,437,258		$ 17,664,316	$ 16,907,213

Fair Values Of Assets And Lia84

Fair Values Of Assets And Liabilities (Narrative) (Detail) - USD ($)		3 Months Ended	9 Months Ended
		Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		$ 2,214,281,000	$ 2,214,281,000	$ 1,792,078,000	$ 1,782,648,000
Mortgage loans held-for-sale, at fair value		347,005,000	347,005,000	351,290,000	363,303,000
Impaired loans—collateral based	[1]	$ 113,027,000	113,027,000	127,412,000	129,537,000
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		$ 2,214,281,000	2,214,281,000	1,792,078,000	1,782,648,000
Mortgage servicing rights		7,875,000	7,875,000	8,435,000	8,137,000
Remaining contractual principal balance outstanding, mortgage loans held-for-sale		328,100,000	328,100,000	327,100,000	340,000,000
Mortgage loans held-for-sale, at fair value		347,005,000	347,005,000	351,290,000	363,303,000
Impaired loans—collateral based		73,800,000	73,800,000
Portion at Other than Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans—collateral based		39,200,000	39,200,000
Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		297,342,000	297,342,000	238,529,000	187,103,000
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		54,004,000	54,004,000	51,139,000	52,155,000
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights		7,875,000	7,875,000	8,435,000	8,137,000
Mortgage loans held-for-sale, at fair value		347,005,000	347,005,000	351,290,000	363,303,000
Fair Value, Measurements, Recurring | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		297,342,000	297,342,000	238,529,000	187,103,000
Fair Value, Measurements, Recurring | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		54,004,000	54,004,000	51,139,000	52,155,000
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans—collateral based		73,819,000	73,819,000
Other real estate owned	[2]	80,524,000	80,524,000
Level 3 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights		7,875,000	7,875,000	8,435,000	8,137,000
Mortgage loans held-for-sale, at fair value		$ 0	0	0	0
Level 3 | Fair Value, Measurements, Recurring | Minimum | Mortgage Servicing Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate		9.00%
Fair Value Inputs, Prepayment Rate		9.00%
Level 3 | Fair Value, Measurements, Recurring | Maximum | Mortgage Servicing Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate		13.00%
Fair Value Inputs, Prepayment Rate		29.00%
Level 3 | Fair Value, Measurements, Recurring | Weighted Average | Mortgage Servicing Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate		9.15%
Fair Value Inputs, Prepayment Rate		12.93%
Level 3 | Fair Value, Measurements, Recurring | Municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		$ 68,401,000	68,401,000	58,953,000	50,237,000
Level 3 | Fair Value, Measurements, Recurring | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, at fair value		$ 24,516,000	$ 24,516,000	23,711,000	23,961,000
Level 3 | Fair Value, Measurements, Recurring | Equity securities | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate		2.01%
Level 3 | Fair Value, Measurements, Recurring | Equity securities | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate		2.43%	2.43%
Level 3 | Fair Value, Measurements, Recurring | Equity securities | Weighted Average
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate			2.22%
Level 3 | Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans—collateral based		$ 73,819,000	$ 73,819,000
Other real estate owned		$ 80,524,000	80,524,000
Level 3 | Fair Value, Measurements, Nonrecurring | Minimum | Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
Level 3 | Fair Value, Measurements, Nonrecurring | Maximum | Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount for Lack of Marketability		10.00%
Non-performing
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held-for-sale, at fair value		$ 0	$ 0	$ 0	$ 0
[1]	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.
[2]	Fair value losses recognized, net on other real estate owned include valuation adjustments and charge-offs during the respective period.

Stock-Based Compensation Plan85

Stock-Based Compensation Plans (Weighted Average Assumptions Used To Determine The Options Fair Value) (Detail)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation [Abstract]
Expected dividend yield	0.90%	0.40%
Expected volatility	26.50%	30.80%
Risk-free rate	1.30%	0.70%
Expected option life (in years)	4 years 6 months	4 years 6 months

Stock-Based Compensation Plan86

Stock-Based Compensation Plans (Summary Of Stock Option Activity) (Detail) - USD ($) $ / shares in Units, $ in Thousands		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Common Shares, Outstanding at beginning of the period		1,618,426	1,524,672
Common Shares, Conversion of options of acquired company		16,364
Common Shares, Granted		502,517	366,478
Common Shares, Exercised		(258,836)	(139,928)
Common Shares, Forfeited or canceled		(277,150)	(99,147)
Common Shares, Outstanding at end of the period		1,601,321	1,652,075
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Strike Price, Outstanding at beginning of period		$ 43	$ 42
Weighted Average Strike Price, Conversion of options of acquired company		21.18
Weighted Average Strike Price, Granted		44.36	46.85
Weighted Average Strike Price, Exercised		43.14	33.90
Weighted Average Strike Price, Forfeited or canceled		53.64	50.61
Weighted Average Strike Price, Outstanding at end of period		$ 41.34	$ 43.24
Stock Options, Exercisable		715,101	1,050,665
Stock Options, Weighted Average Strike Price, Exercisable		$ 37.52	$ 43.86
Stock Options, Remaining Contractual Term, Outstanding, Years	[1]	4 years 8 months 12 days	3 years 4 months 24 days
Stock Options, Remaining Contractual Term, Exercisable, Years	[1]	3 years 2 months 12 days	2 years 1 month 6 days
Stock Options, Intrinsic Value, Outstanding	[2]	$ 19,378	$ 8,133
Stock Options, Intrinsic Value, Exercisable	[2]	$ 11,376	$ 5,851
[1]	Represents the remaining weighted average contractual life in years.
[2]	Aggregate intrinsic value represents the total pre-tax intrinsic value (i.e., the difference between the Company's stock price on the last trading day of the quarter 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 quarter. Options with exercise prices above the stock price on the last trading day of the quarter are excluded from the calculation of intrinsic value. The intrinsic value will change based on the fair market value of the Company's stock.

Stock-Based Compensation Plan87

Stock-Based Compensation Plans (Summary Of Plans' Restricted Share And Performance-Vested Stock Award Activity) (Detail) - $ / shares	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Shares, Beginning of the Period	146,112	181,522
Shares, Granted	15,657	12,313
Shares, Vested and issued	(20,409)	(51,978)
Shares, Forfeited	(2,400)	(6,752)
Shares, Outstanding, End of the Period	138,960	135,105
Shares, Vested, but not issuable	85,000	85,000
Weighted Average Grant-Date Fair Value	$ 48.68	$ 47.09	$ 47.45	$ 43.39
Weighted Average Grant-Date Fair Value, Granted	45.81	46.04
Weighted Average Grant-Date Fair Value, Vested and issued	39.07	35.12
Weighted Average Grant-Date Fair Value, Forfeited	36.81	37.95
Weighted Average Grant-Date Fair Value, Vested, but not issuable	$ 51.88	$ 51.88
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Shares, Beginning of the Period	295,679	307,512
Shares, Granted	106,017	93,535
Shares, Vested and issued	(78,590)	(15,944)
Shares, Forfeited	(33,854)	(89,424)
Shares, Outstanding, End of the Period	289,252	295,679
Weighted Average Grant-Date Fair Value	$ 43	$ 38.18	$ 38.18	$ 34.01
Weighted Average Grant-Date Fair Value, Granted	44.35	46.85
Weighted Average Grant-Date Fair Value, Vested and issued	31.10	33.25
Weighted Average Grant-Date Fair Value, Forfeited	$ 32.74	$ 33.78

Stock-Based Compensation Plan88

Stock-Based Compensation Plans (Narrative) (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2015	Sep. 30, 2014	May. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 2.5	$ 2.2		$ 7.8	$ 8.1
Allocated Sharebased Compensation Expense Modification Of Performance Measurement			$ 2.1
Weighted average grant date fair value per share of options granted				$ 9.72	$ 11.96
Aggregate intrinsic value of options exercised				$ 2.3	$ 1.8
Two Thousand And Fifteen Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares approved for issuance						5,485,000
Two Thousand And Seven Plan And Two Thousand And Fifteen Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				3 years
Two Thousand And Seven Plan And Two Thousand And Fifteen Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				5 years
Share based payment award options term				7 years
Nineteen Ninety Seven Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based payment award options term				10 years
Restricted Stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				1 year
Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				5 years
Ltip Awards | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Performance Based Award Payouts				0.00%
Granted in Two Thousand Fifteen | Ltip Awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Performance Based Award Payouts				150.00%
Granted Prior To Two Thousand Fifteen | Ltip Awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Performance Based Award Payouts				200.00%

Shareholders' Equity And Earn89

Shareholders' Equity And Earnings Per Share (Components Of Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (61,871)	$ (34,503)	$ (37,332)	$ (63,036)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	12,371	(8,621)	(12,394)	19,078
Amount reclassified from accumulated other comprehensive income (loss), net of tax	407	424	633	1,258
Other comprehensive income, net of tax	12,778	(8,197)	(11,761)	20,336
Balance at end of period	(49,093)	(42,700)	(49,093)	(42,700)
Accumulated Unrealized Gains (Losses) on Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(26,333)	(24,003)	(9,533)	(53,665)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	18,995	812	2,499	30,251
Amount reclassified from accumulated other comprehensive income (loss), net of tax	60	91	(244)	314
Other comprehensive income, net of tax	19,055	903	2,255	30,565
Balance at end of period	(7,278)	(23,100)	(7,278)	(23,100)
Accumulated Unrealized Losses on Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(2,727)	(2,898)	(2,517)	(2,462)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	(287)	252	(1,027)	(795)
Amount reclassified from accumulated other comprehensive income (loss), net of tax	347	333	877	944
Other comprehensive income, net of tax	60	585	(150)	149
Balance at end of period	(2,667)	(2,313)	(2,667)	(2,313)
Accumulated Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(32,811)	(7,602)	(25,282)	(6,909)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	(6,337)	(9,685)	(13,866)	(10,378)
Amount reclassified from accumulated other comprehensive income (loss), net of tax	0	0	0	0
Other comprehensive income, net of tax	(6,337)	(9,685)	(13,866)	(10,378)
Balance at end of period	$ (39,148)	$ (17,287)	$ (39,148)	$ (17,287)

Shareholders' Equity and Earn90

Shareholders' Equity and Earnings Per Share Shareholders' Equity And Earnings Per Share (Other Comprehensive Income Reclassified from AOCI) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
(Losses) gains on available-for-sale securities, net	$ (98)	$ (153)	$ 402	$ (522)
Interest on deposits	12,436	12,298	36,246	35,980
Interest on junior subordinated debentures	2,124	2,091	6,034	6,137
Income before taxes	62,197	65,258	195,358	184,629
Income tax expense	(23,842)	(25,034)	(74,120)	(71,364)
Net income	38,355	40,224	121,238	113,265
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Accumulated Unrealized Losses on Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
(Losses) gains on available-for-sale securities, net	(98)	(153)	402	(522)
Income before taxes	(98)	(153)	402	(522)
Income tax expense	38	62	(158)	208
Net income	(60)	(91)	244	(314)
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Accumulated Unrealized Losses on Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest on deposits	92	0	92	0
Interest on junior subordinated debentures	479	553	1,350	1,567
Income before taxes	(571)	(553)	(1,442)	(1,567)
Income tax expense	224	220	565	623
Net income	$ (347)	$ (333)	$ (877)	$ (944)

Shareholders' Equity And Earn91

Shareholders' Equity And Earnings Per Share (Computation Of Basic And Diluted Earnings Per Common Share) (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract]
Net income	$ 38,355	$ 40,224	$ 121,238	$ 113,265
Less: Preferred stock dividends and discount accretion	4,079	1,581	7,240	4,743
Net income applicable to common shares—Basic	34,276	38,643	113,998	108,522
Add: Dividends on convertible preferred stock, if dilutive	1,579	1,581	4,740	4,743
Net income applicable to common shares—Diluted	$ 35,855	$ 40,224	$ 118,738	$ 113,265
Weighted average common shares outstanding	48,158	46,639	47,658	46,453
Effect of dilutive potential common shares
Common stock equivalents	978	1,166	1,070	1,274
Convertible preferred stock, if dilutive	3,071	3,075	3,071	3,075
Total dilutive potential common shares	4,049	4,241	4,141	4,349
Weighted average common shares and effect of dilutive potential common shares	52,207	50,880	51,799	50,802
Net income per common share-Basic	$ 0.71	$ 0.83	$ 2.39	$ 2.34
Net income per common share-Diluted	$ 0.69	$ 0.79	$ 2.29	$ 2.23

Shareholders' Equity And Earn92

Shareholders' Equity And Earnings Per Share (Narrative) (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 20, 2015	Aug. 06, 2015	May. 21, 2015	May. 07, 2015	Feb. 19, 2015	Feb. 05, 2015	Dec. 19, 2008	Jul. 31, 2015	Jun. 30, 2015	Apr. 30, 2015	Jan. 31, 2015	Mar. 31, 2012	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Jun. 25, 2015
Temporary Equity [Line Items]
Cash dividends declared per common share								$ 0.11		$ 0.11	$ 0.11		$ 0.11	$ 0.10	$ 0.33	$ 0.30
Common stock dividends per share declared annualized								$ 0.44		$ 0.44	$ 0.44
Dividends payable, date to be paid	Aug. 20, 2015		May 21, 2015		Feb. 19, 2015
Dividends payable, date of record		Aug. 6, 2015		May 7, 2015		Feb. 5, 2015
Community Financial Shares, Inc.
Temporary Equity [Line Items]
Common stock, shares issued, acquisition								388,573
Delavan Bancshares
Temporary Equity [Line Items]
Common stock, shares issued, acquisition											422,122
US Treasury
Temporary Equity [Line Items]
Warrants outstanding							1,643,295						383,352		383,352
Investment warrants, exercise price							$ 22.82
Warrant termination period							10 years
Warrants exercised															554,065
Common stock, shares, issued from exercise of warrant shares															304,915
Series D Preferred Stock
Temporary Equity [Line Items]
Preferred stock, shares issued																		5,000,000,000,000
Preferred stock, liquidation value per share													$ 25	$ 0	$ 25	$ 0	$ 0	$ 25
Preferred stock, value													$ 125,000	$ 0	$ 125,000	$ 0	$ 0	$ 125,000
Preferred stock, Dividend payment terms									quarterly
Preferred stock, dividend rate, percentage									6.50%
Series C Preferred Stock
Temporary Equity [Line Items]
Preferred stock, shares issued												126,500
Preferred stock, liquidation value per share												$ 1,000	$ 1,000	$ 1,000	$ 1,000	$ 1,000	$ 1,000
Preferred stock, value												$ 126,500	$ 126,312	$ 126,467	$ 126,312	$ 126,467	$ 126,467
Preferred stock, Dividend payment terms												quarterly
Preferred stock, dividend rate, percentage												5.00%
Convertible preferred stock, terms of conversion												24.3132
Preferred stock, shares converted															155		10
Common stock, shares, conversion of preferred stock															3,767		244
London Interbank Offered Rate (LIBOR) | Series D Preferred Stock
Temporary Equity [Line Items]
Preferred stock, dividend rate, percentage, variable spread									4.06%