First Midwest Bancorp (ONBPP) 10-Q 8 Aug 17 2017 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Aug. 04, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	FIRST MIDWEST BANCORP INC
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		102,737,430
Amendment Flag	false
Entity Central Index Key	702,325
Entity Filer Category	Large Accelerated Filer
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2

Consolidated Statements of Fina

Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets
Cash and due from banks	$ 181,171	$ 155,055
Interest-bearing deposits in other banks	103,181	107,093
Trading securities, at fair value	19,545	17,920
Securities available-for-sale, at fair value	1,908,248	1,919,450
Securities held-to-maturity, at amortized cost	17,353	22,291
Federal Home Loan Bank (FHLB) and Federal Reserve Bank (FRB) stock, at cost	66,333	59,131
Loans	10,232,159	8,254,145
Allowance for loan losses	(92,371)	(86,083)
Net loans	10,139,788	8,168,062
Other real estate owned (OREO)	26,493	26,083
Premises, furniture, and equipment, net	135,745	82,577
Investment in bank-owned life insurance (BOLI)	278,353	219,746
Goodwill and other intangible assets	752,413	366,876
Accrued interest receivable and other assets	340,517	278,271
Total assets	13,969,140	11,422,555
Liabilities
Noninterest-bearing deposits	3,525,905	2,766,748
Interest-bearing deposits	7,473,815	6,061,855
Total deposits	10,999,720	8,828,603
Borrowed funds	639,333	879,008
Senior and subordinated debt	194,886	194,603
Accrued interest payable and other liabilities	298,358	263,261
Total liabilities	12,132,297	10,165,475
Stockholders' Equity
Common stock	1,123	913
Additional paid-in capital	1,025,607	498,937
Retained earnings	1,056,072	1,016,674
Accumulated other comprehensive loss, net of tax	(36,567)	(40,910)
Treasury stock, at cost	(209,392)	(218,534)
Total stockholders' equity	1,836,843	1,257,080
Total liabilities and stockholders' equity	$ 13,969,140	$ 11,422,555
Stockholders' Equity, Number of Shares, Par Value, and Other Disclosures
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Common stock, shares authorized	250,000,000	150,000,000
Common stock, shares issued	112,345,000	91,284,000
Common stock, shares outstanding	102,741,000	81,325,000
Treasury stock, shares	9,604,000	9,959,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Interest Income
Loans	$ 114,820	$ 86,526	$ 227,185	$ 164,981
Investment securities	10,527	9,363	21,011	17,921
Other short-term investments	1,169	661	2,019	1,196
Total interest income	126,516	96,550	250,215	184,098
Interest Expense
Deposits	3,729	2,482	6,938	4,867
Borrowed funds	2,099	1,499	4,293	2,815
Senior and subordinated debt	3,105	2,588	6,204	5,721
Total interest expense	8,933	6,569	17,435	13,403
Net interest income	117,583	89,981	232,780	170,695
Provision for loan losses	8,239	8,085	13,157	15,678
Net interest income after provision for loan losses	109,344	81,896	219,623	155,017
Noninterest Income
Service charges on deposit accounts	12,153	10,169	23,518	19,642
Wealth management fees	10,525	8,642	20,185	16,201
Card-based fees	8,832	7,592	16,948	14,310
Capital market products income	2,217	2,066	3,593	5,281
Mortgage banking income	1,645	1,863	3,533	3,231
Other service charges, commissions, and fees	5,856	5,602	11,298	10,863
Net securities gains	284	23	284	910
Other income	3,433	1,865	5,537	3,310
Total noninterest income	44,945	37,822	84,896	73,748
Noninterest Expense
Salaries and employee benefits	54,575	46,267	110,347	90,861
Net occupancy and equipment expense	12,485	9,928	24,810	19,625
Professional services	9,112	5,292	17,575	11,212
Technology and related costs	4,485	3,669	8,918	7,370
Net OREO expense	1,631	1,122	3,331	1,786
Other expenses	16,289	14,458	31,673	27,451
Acquisition and integration related expenses	1,174	618	19,739	5,638
Total noninterest expense	99,751	81,354	216,393	163,943
Income before income tax expense	54,538	38,364	88,126	64,822
Income tax expense	19,588	13,097	30,321	21,593
Net income	$ 34,950	$ 25,267	$ 57,805	$ 43,229
Per Common Share Data
Basic earnings per common share (in dollars per share)	$ 0.34	$ 0.31	$ 0.57	$ 0.54
Diluted earnings per common share (in dollars per share)	0.34	0.31	0.57	0.54
Dividends declared per common share (in dollars per share)	$ 0.10	$ 0.09	$ 0.19	$ 0.18
Weighted-average common shares outstanding (in Shares)	101,743	80,383	101,081	79,182
Weighted-average diluted common shares outstanding (in Shares)	101,763	80,396	101,101	79,194

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 34,950	$ 25,267	$ 57,805	$ 43,229
Unrealized holding gains:
Before tax	7,352	9,493	10,650	28,366
Tax effect	(2,941)	(3,795)	(4,262)	(11,341)
Net of tax	4,411	5,698	6,388	17,025
Reclassification of net gains included in net income:
Before tax	284	23	284	910
Tax effect	(114)	(9)	(114)	(364)
Net of tax	170	14	170	546
Net unrealized holding gains	4,241	5,684	6,218	16,479
Derivative Instruments
Before tax	(905)	924	(3,125)	5,199
Tax effect	361	(370)	1,250	(2,092)
Net of tax	(544)	554	(1,875)	3,107
Total other comprehensive income	3,697	6,238	4,343	19,586
Total comprehensive income	$ 38,647	$ 31,505	$ 62,148	$ 62,815

Consolidated Statements of Com5

Consolidated Statements of Comprehensive Income - AOCI - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income	$ 4,343	$ 19,586
Accumulated Unrealized Gain (Loss) on Securities Available- for-Sale
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(22,645)	(10,271)
Other comprehensive income	6,218	16,479
Ending balance	(16,427)	6,208
Accumulated Unrealized Gain (Loss) on Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(1,176)	(2,468)
Other comprehensive income	(1,875)	3,107
Ending balance	(3,051)	639
Unrecognized Net Pension Costs
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(17,089)	(15,650)
Other comprehensive income	0	0
Ending balance	(17,089)	(15,650)
Total Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(40,910)	(28,389)
Other comprehensive income	4,343	19,586
Ending balance	$ (36,567)	$ (8,803)

Consolidated Statements of Chan

Consolidated Statements of Changes In Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Balance Beginning at Dec. 31, 2015	$ 1,146,268	$ 882	$ 446,672	$ 953,516	$ (28,389)	$ (226,413)
Balance Beginning (in Shares) at Dec. 31, 2015		77,952
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	43,229			43,229
Other comprehensive income	19,586				19,586
Common dividends declared ($0.18 and $0.19 per common share in 2016 and 2017, respectively)	(14,468)			(14,468)
Acquisitions, net of issuance costs	54,896	$ 31	54,865
Acquisitions, net of issuance costs (in Shares)		3,042
Common stock issued	112		112
Common stock issued (in Shares)		7
Restricted stock activity	(2,500)		(10,319)			7,819
Restricted stock activity (in Shares)		316
Treasury stock issued to benefit plans	(71)		(8)			(63)
Treasury stock issued to benefit plans (in Shares)		(5)
Share-based compensation expense	3,837		3,837
Balance Ending at Jun. 30, 2016	1,250,889	$ 913	495,159	982,277	(8,803)	(218,657)
Balance Ending (in Shares) at Jun. 30, 2016		81,312
Balance Beginning at Dec. 31, 2016	$ 1,257,080	$ 913	498,937	1,016,674	(40,910)	(218,534)
Balance Beginning (in Shares) at Dec. 31, 2016	81,325	81,325
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 57,805			57,805
Other comprehensive income	4,343				4,343
Common dividends declared ($0.18 and $0.19 per common share in 2016 and 2017, respectively)	(18,407)			(18,407)
Acquisitions, net of issuance costs	534,090	$ 210	533,322			558
Acquisitions, net of issuance costs (in Shares)		21,078
Common stock issued	110		110
Common stock issued (in Shares)		5
Restricted stock activity	(3,840)		(12,588)			8,748
Restricted stock activity (in Shares)		340
Treasury stock issued to benefit plans	(165)		(1)			(164)
Treasury stock issued to benefit plans (in Shares)		(7)
Share-based compensation expense	5,827		5,827
Balance Ending at Jun. 30, 2017	$ 1,836,843	$ 1,123	$ 1,025,607	$ 1,056,072	$ (36,567)	$ (209,392)
Balance Ending (in Shares) at Jun. 30, 2017	102,741	102,741

Consolidated Statements of Cha7

Consolidated Statements of Changes In Stockholders' Equity (Parentheticals) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Stockholders' Equity [Abstract]
Dividends declared per common share (in dollars per share)	$ 0.10	$ 0.09	$ 0.19	$ 0.18

Condensed Consolidated Stateme8

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Statement of Cash Flows [Abstract]
Net cash provided by operating activities	$ 81,423	$ 59,238
Investing Activities
Proceeds from maturities, repayments, and calls of securities available-for-sale	158,946	174,937
Proceeds from sales of securities available-for-sale	241,137	40,043
Purchases of securities available-for-sale	(172,451)	(532,934)
Proceeds from maturities, repayments, and calls of securities held-to-maturity	4,948	4,360
Purchases of securities held-to-maturity	(10)	(16)
Net purchases of FHLB stock	(3,955)	(3,651)
Net increase in loans	(225,537)	(432,283)
Premiums paid on BOLI, net of proceeds from claims	(6)	1,599
Proceeds from sales of OREO	8,476	3,852
Proceeds from sales of premises, furniture, and equipment	7,056	3,213
Purchases of premises, furniture, and equipment	(6,619)	(7,536)
Net cash received from acquisitions	41,717	57,347
Net cash provided by (used in) investing activities	53,702	(691,069)
Financing Activities
Net increase in deposit accounts	147,243	278,657
Net (decrease) increase in borrowed funds	(239,675)	282,232
Payments for the maturity of subordinated debt	0	(38,500)
Cash dividends paid	(16,485)	(14,123)
Restricted stock activity	(4,004)	(2,248)
Net cash (used in) provided by financing activities	(112,921)	506,018
Net increase (decrease) in cash and cash equivalents	22,204	(125,813)
Cash and cash equivalents at beginning of period	262,148	381,202
Cash and cash equivalents at end of period	284,352	255,389
Supplemental Disclosures of Cash Flow Information:
Income taxes (refunded) paid	(958)	7,427
Interest paid to depositors and creditors	16,381	13,269
Dividends declared, but unpaid	9,165	7,595
Stock issued for acquisitions, net of issuance costs	534,090	54,896
Non-cash transfers of loans to OREO	1,982	3,675
Non-cash transfers of loans held-for-investment to loans held-for-sale	$ 31,564	$ 63,709

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation – The accompanying unaudited condensed consolidated interim financial statements ("consolidated financial statements") of First Midwest Bancorp, Inc. (the " Company "), a Delaware corporation, were prepared in accordance with the rules and regulations of the Securities and Exchange Commission (" SEC ") for quarterly reports on Form 10-Q and reflect all adjustments that management deems necessary for the fair presentation of the financial position and results of operations for the periods presented. The results of operations for the quarter and six months ended June 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 . The accounting and reporting policies of the Company and its subsidiaries conform to U.S. generally accepted accounting principles (" GAAP ") and general practices within the banking industry. The accompanying consolidated financial statements do not include certain information and note disclosures required by GAAP for complete annual financial statements. Therefore, these financial statements should be read in conjunction with the Company 's 2016 Annual Report on Form 10-K (" 2016 10-K"). The Company uses the accrual basis of accounting for financial reporting purposes. Certain reclassifications were made to prior year amounts to conform to the current year presentation. Use of Estimates – The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Although these estimates and assumptions are based on the best available information, actual results could differ from those estimates. Principles of Consolidation – The accompanying consolidated financial statements include the financial position and results of operations of the Company and its subsidiaries after elimination of all significant intercompany accounts and transactions. Assets held in a fiduciary or agency capacity are not assets of the Company or its subsidiaries and are not included in the consolidated financial statements. The accounting policies related to business combinations, loans, the allowance for credit losses, and derivative financial instruments are presented below. For a summary of all other significant accounting policies, see Note 1, "Summary of Significant Accounting Policies," in the Company 's 2016 10-K. Business Combinations – Business combinations are accounted for under the acquisition method of accounting. Assets acquired and liabilities assumed are recorded at their estimated fair values as of the date of acquisition, with any excess of the purchase price of the acquisition over the fair value of the identifiable net tangible and intangible assets acquired recorded as goodwill. Alternatively, a gain is recorded if the fair value of assets purchased exceeds the fair value of liabilities assumed and consideration paid. The results of operations of the acquired business are included in the Condensed Consolidated Statements of Income from the effective date of the acquisition. Loans – Loans held-for-investment are loans that the Company intends to hold until they are paid in full and are carried at the principal amount outstanding, including certain net deferred loan origination fees. Loan origination fees, commitment fees, and certain direct loan origination costs are deferred, and the net amount is amortized as a yield adjustment over the contractual life of the related loans or commitments and included in interest income. Fees related to letters of credit are amortized into fee income over the contractual life of the commitment. Other credit-related fees are recognized as fee income when earned. The Company 's net investment in direct financing leases is included in loans and consists of future minimum lease payments and estimated residual values, net of unearned income. Interest income on loans is accrued based on principal amounts outstanding. Loans held-for-sale are carried at the lower of aggregate cost or fair value and included in other assets in the Consolidated Statements of Financial Condition. Acquired and Covered Loans – Covered loans consists of loans acquired by the Company in Federal Deposit Insurance Corporation (" FDIC ")-assisted transactions, which are covered by loss share agreements with the FDIC (the " FDIC Agreements "), under which the FDIC reimburses the Company for the majority of the losses and eligible expenses related to these assets during the coverage period. Acquired loans consist of all other loans that were acquired in business combinations that are not covered by the FDIC Agreements. Certain loans that were previously classified as covered loans are no longer covered under the FDIC Agreements, and are included in acquired loans. Covered loans and acquired loans are included within loans held-for-investment. Acquired and covered loans are separated into (i) non-purchased credit impaired (" non-PCI ") and (ii) purchased credit impaired (" PCI ") loans. Non-PCI loans include loans that did not have evidence of credit deterioration since origination at the acquisition date. PCI loans include loans that had evidence of credit deterioration since origination and for which it was probable at acquisition that the Company would not collect all contractually required principal and interest payments. Evidence of credit deterioration was evaluated using various indicators, such as past due and non-accrual status. Leases and revolving loans do not qualify to be accounted for as PCI loans and are accounted for as non-PCI loans. The acquisition adjustment related to non-PCI loans is amortized into interest income over the contractual life of the related loans. If an acquired non-PCI loan is renewed subsequent to the acquisition date, any remaining acquisition adjustment is accreted into interest income and the loan is considered a new loan that is no longer classified as an acquired loan. PCI loans are accounted for based on estimates of expected future cash flows. To estimate the fair value, the Company generally aggregates purchased consumer loans and commercial loans into pools of loans with common risk characteristics, such as delinquency status, credit score, and internal risk ratings. The fair values of larger balance commercial loans are estimated on an individual basis. Expected future cash flows in excess of the fair value of loans at the purchase date ("accretable yield") are recorded as interest income over the life of the loans if the timing and amount of the expected future cash flows can be reasonably estimated. The non-accretable yield represents the difference between contractually required payments and the expected future cash flows determined at acquisition. Subsequent increases in expected future cash flows are offset against the allowance for credit losses to the extent an allowance has been established or otherwise recognized as interest income prospectively. The present value of any decreases in expected future cash flows is recognized by recording a charge-off through the allowance for loan losses or providing an allowance for loan losses. 90-Days Past Due Loans –The Company 's accrual of interest on loans is generally discontinued at the time the loan is 90 days past due unless the credit is sufficiently collateralized and in the process of renewal or collection. Non-accrual Loans – Generally, corporate loans are placed on non-accrual status (i) when either principal or interest payments become 90 days or more past due unless the credit is sufficiently collateralized and in the process of renewal or collection, or (ii) when an individual analysis of a borrower's creditworthiness warrants a downgrade to non-accrual regardless of past due status. When a loan is placed on non-accrual status, unpaid interest credited to income in the current year is reversed, and unpaid interest accrued in prior years is charged against the allowance for loan losses. After the loan is placed on non-accrual status, all debt service payments are applied to the principal on the loan. Future interest income may only be recorded on a cash basis after recovery of principal is reasonably assured. Non-accrual loans are returned to accrual status when the financial position of the borrower and other relevant factors indicate that the Company will collect all principal and interest. Commercial loans and loans secured by real estate are charged-off when deemed uncollectible. A loss is recorded if the net realizable value of the underlying collateral is less than the outstanding principal and interest. Consumer loans that are not secured by real estate are subject to mandatory charge-off at a specified delinquency date and are usually not classified as non-accrual prior to being charged-off. Closed-end consumer loans, which include installment, automobile, and single payment loans, are usually charged-off no later than the end of the month in which the loan becomes 120 days past due. PCI loans are generally considered accruing loans unless reasonable estimates of the timing and amount of expected future cash flows cannot be determined. Loans without reasonable future cash flow estimates are classified as non-accrual loans, and interest income is not recognized on those loans until the timing and amount of the expected future cash flows can be reasonably determined. Troubled Debt Restructurings ( " TDR s" ) – A restructuring is considered a TDR when (i) the borrower is experiencing financial difficulties, and (ii) the creditor grants a concession, such as forgiveness of principal, reduction of the interest rate, changes in payments, or extension of the maturity date. Loans are not classified as TDR s when the modification is short-term or results in an insignificant delay in payments. The Company 's TDR s are determined on a case-by-case basis. The Company does not accrue interest on a TDR unless it believes collection of all principal and interest under the modified terms is reasonably assured. For a TDR to begin accruing interest, the borrower must demonstrate some level of past performance and the future capacity to perform under the modified terms. Generally, six months of consecutive payment performance under the restructured terms is required before a TDR is returned to accrual status. However, the period could vary depending on the individual facts and circumstances of the loan. An evaluation of the borrower's current creditworthiness is used to assess the borrower's capacity to repay the loan under the modified terms. This evaluation includes an estimate of expected future cash flows, evidence of strong financial position, and estimates of the value of collateral, if applicable. For TDR s to be removed from TDR status in the calendar year after the restructuring, the loans must (i) have an interest rate and terms that reflect market conditions at the time of restructuring, and (ii) be in compliance with the modified terms. If the loan was restructured at below market rates and terms, it continues to be separately reported as restructured until it is paid in full or charged-off. Impaired Loans – Impaired loans consist of corporate non-accrual loans and TDR s. A loan is considered impaired when it is probable that the Company will not collect all contractual principal and interest. With the exception of accruing TDR s, impaired loans are classified as non-accrual and are exclusive of smaller homogeneous loans, such as home equity, 1-4 family mortgages, and installment loans. Impaired loans with balances under a specified threshold are not individually evaluated for impairment. For all other impaired loans, impairment is measured by comparing the estimated value of the loan to the recorded book value. The value of collateral-dependent loans is based on the fair value of the underlying collateral, less costs to sell. The value of other loans is measured using the present value of expected future cash flows discounted at the loan's initial effective interest rate. Allowance for Credit Losses – The allowance for credit losses is comprised of the allowance for loan losses and the reserve for unfunded commitments, and is maintained by management at a level believed adequate to absorb estimated losses inherent in the existing loan portfolio. Determination of the allowance for credit losses is subjective since it requires significant estimates and management judgment, including the amounts and timing of expected future cash flows on impaired loans, estimated losses on pools of homogeneous loans, consideration of current economic trends, and other factors. Loans deemed to be uncollectible are charged-off against the allowance for loan losses, while recoveries of amounts previously charged-off are credited to the allowance for loan losses. Additions to the allowance for loan losses are charged to expense through the provision for loan losses. The amount of provision depends on a number of factors, including net charge-off levels, loan growth, changes in the composition of the loan portfolio, and the Company 's assessment of the allowance for loan losses based on the methodology discussed below. Allowance for Loan Losses – The allowance for loan losses consists of (i) specific reserves for individual loans where the recorded investment exceeds the value, (ii) an allowance based on a loss migration analysis that uses historical credit loss experience for each loan category, and (iii) an allowance based on other internal and external qualitative factors. The specific reserves component of the allowance for loan losses is based on a periodic analysis of impaired loans exceeding a fixed dollar amount. If the value of an impaired loan is less than the recorded book value, the Company either establishes a valuation allowance (i.e., a specific reserve) equal to the excess of the book value over the collateral value of the loan as a component of the allowance for loan losses or charges off the amount if it is a confirmed loss. The general reserve component is based on a loss migration analysis, which examines actual loss experience by loan category for a rolling 8-quarter period and the related internal risk rating for corporate loans. The loss migration analysis is updated quarterly primarily using actual loss experience. This component is then adjusted based on management's consideration of many internal and external qualitative factors, including: • Changes in the composition of the loan portfolio, trends in the volume of loans, and trends in delinquent and non-accrual loans that could indicate that historical trends do not reflect current conditions. • Changes in credit policies and procedures, such as underwriting standards and collection, charge-off, and recovery practices. • Changes in the experience, ability, and depth of credit management and other relevant staff. • Changes in the quality of the Company 's loan review system and Board of Directors oversight. • The effect of any concentration of credit and changes in the level of concentrations, such as loan type or risk rating. • Changes in the value of the underlying collateral for collateral-dependent loans. • Changes in the national and local economy that affect the collectability of various segments of the portfolio. • The effect of other external factors, such as competition and legal and regulatory requirements, on the Company 's loan portfolio. The allowance for loan losses also consists of an allowance on acquired and covered non-PCI and PCI loans. No allowance for loan losses is recorded on acquired loans at the acquisition date. Subsequent to the acquisition date, an allowance for credit losses is established as necessary to reflect credit deterioration. The acquired non-PCI allowance is based on management's evaluation of the acquired non-PCI loan portfolio giving consideration to the current portfolio balance including the remaining acquisition adjustments, maturity dates, and overall credit quality. The allowance for covered non-PCI loans is calculated in the same manner as the general reserve component based on a loss migration analysis as discussed above. The acquired and covered PCI allowance reflects the difference between the carrying value and the discounted expected future cash flows of the acquired and covered PCI loans. On a periodic basis, the adequacy of this allowance is determined through a re-estimation of expected future cash flows on all of the outstanding acquired and covered PCI loans using either a probability of default/loss given default (" PD/LGD ") methodology or a specific review methodology. The PD/LGD model is a loss model that estimates expected future cash flows using a probability of default curve and loss given default estimates. Acquired non-PCI loans that have renewed subsequent to the respective acquisition dates are no longer classified as acquired loans. Instead, they are included in the general loan population and allocated an allowance based on a loss migration analysis. Reserve for Unfunded Commitments – The Company also maintains a reserve for unfunded commitments, including letters of credit, for the risk of loss inherent in these arrangements. The reserve for unfunded commitments is estimated using the loss migration analysis from the allowance for loan losses, adjusted for probabilities of future funding requirements. The reserve for unfunded commitments is included in other liabilities in the Consolidated Statements of Financial Condition. The establishment of the allowance for credit losses involves a high degree of judgment given the difficulty of assessing the factors impacting loan repayment and estimating the timing and amount of losses. While management utilizes its best judgment and information available, the adequacy of the allowance for credit losses depends on a variety of factors beyond the Company 's control, including the performance of its loan portfolio, the economy, changes in interest rates and property values, and the interpretation of loan risk classifications by regulatory authorities. Derivative Financial Instruments – To provide derivative products to customers and in the ordinary course of business, the Company enters into derivative transactions as part of its overall interest rate risk management strategy to minimize significant unplanned fluctuations in earnings and expected future cash flows caused by interest rate volatility. All derivative instruments are recorded at fair value as either other assets or other liabilities in the Consolidated Statements of Financial Condition. Subsequent changes in a derivative's fair value are recognized in earnings unless specific hedge accounting criteria are met. On the date the Company enters into a derivative contract, the derivative is designated as a fair value hedge, a cash flow hedge, or a non-hedge derivative instrument. Fair value hedges are designed to mitigate exposure to changes in the fair value of an asset or liability attributable to a particular risk, such as interest rate risk. Cash flow hedges are designed to mitigate exposure to variability in expected future cash flows to be received or paid related to an asset, liability, or other type of forecasted transaction. The Company formally documents all relationships between hedging instruments and hedged items, including its risk management objective and strategy at inception. At the hedge's inception and quarterly thereafter, a formal assessment is performed to determine the effectiveness of the derivative in offsetting changes in the fair values or expected future cash flows of the hedged items in the current period and prospectively. If a derivative instrument designated as a hedge is terminated or ceases to be highly effective, hedge accounting is discontinued prospectively, and the gain or loss is amortized into earnings. For fair value hedges, the gain or loss is amortized over the remaining life of the hedged asset or liability. For cash flow hedges, the gain or loss is amortized over the same period that the forecasted hedged transactions impact earnings. If the hedged item is disposed of, any fair value adjustments are included in the gain or loss from the disposition of the hedged item. If the forecasted transaction is no longer probable, the gain or loss is included in earnings immediately. For fair value hedges, changes in the fair value of the derivative instruments, as well as changes in the fair value of the hedged item, are recognized in earnings. For cash flow hedges, the effective portion of the change in fair value of the derivative instrument is reported as a component of accumulated other comprehensive loss and is reclassified to earnings when the hedged transaction is reflected in earnings. Ineffectiveness is calculated based on the change in fair value of the hedged item compared with the change in fair value of the hedging instrument. For all types of hedges, any ineffectiveness in the hedging relationship is recognized in earnings during the period the ineffectiveness occurs.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	6 Months Ended
	Jun. 30, 2017
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	RECENT ACCOUNTING PRONOUNCEMENTS Adopted Accounting Pronouncements Contingent Put and Call Options in Debt Instruments: In March of 2016, the Financial Accounting Standards Board ("FASB") issued final guidance clarifying the requirements for assessing whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. Entities are required to apply the guidance to existing debt instruments (or hybrid financial instruments that are determined to have a debt host) using a modified retrospective transition method as of the period of adoption. The adoption of this guidance on January 1, 2017 did not impact the Company 's financial condition, results of operations, or liquidity. Equity Method Accounting: In March of 2016, the FASB issued final guidance to simplify the equity method of accounting. The guidance eliminates the requirement to retrospectively apply equity method accounting in previous periods when an investor initially obtains significant influence over an investee. This guidance is effective for annual and interim periods beginning after December 15, 2016. The adoption of this guidance on January 1, 2017 did not impact the Company 's financial condition, results of operations, or liquidity. Accounting for Employee Share-based Payments: In March of 2016, the FASB issued guidance to simplify the accounting for employee share-based payment transactions. The guidance requires entities to recognize the income tax effects of awards in the income statement when the awards vest or are settled. In addition, the guidance allows entities to repurchase more of an employee's shares than it can under current guidance for tax withholding purposes without triggering liability accounting and to make a policy election to account for forfeitures as they occur. The adoption of this guidance on January 1, 2017 resulted in a $638,000 tax benefit to the provision for income tax expense for the six months ended June 30, 2017 , recorded in the Company's results of operations. The Company elected to estimate forfeitures, which is consistent with the Company's practice before the adoption of this guidance. Accounting Pronouncements Pending Adoption Revenue from Contracts with Customers: In May of 2014, the FASB issued guidance that requires an entity to 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. In March of 2016, the FASB issued an amendment to this guidance to clarify the implementation of guidance on principal versus agent consideration. Additional amendments to clarify the implementation guidance on the identification of performance obligations and licensing were issued in April of 2016 and narrow-scope improvements and practical expedients were issued in May of 2016. The guidance was initially effective for annual and interim reporting periods beginning on or after December 15, 2016 but was deferred to December 15, 2017, and must be applied either retrospectively or using the modified retrospective approach. Early adoption is permitted, but not before the original effective date. The Company's revenue is comprised of net interest income on financial assets and liabilities, which are excluded from the scope of this guidance, and noninterest income. The Company expects that this guidance will change how revenue from certain revenue streams is recognized within wealth management fees but does not expect these changes to have a significant impact on the Company's financial condition, results of operations, or liquidity. The Company continues to evaluate the impact of this guidance on other components of noninterest income. The Company will adopt this guidance on January 1, 2018, using the modified retrospective approach with a cumulative effect adjustment to opening retained earnings, if an adjustment is deemed to be significant. Amendments to Guidance on Classifying and Measuring Financial Instruments: In January of 2016, the FASB issued guidance that will require entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value. Any changes in fair value will be recognized in net income unless the investments qualify for a new practicability exception. This guidance also requires entities to recognize changes in instrument-specific credit risk related to financial liabilities measured under the fair value option in other comprehensive income. No changes were made to the guidance for classifying and measuring investments in debt securities and loans. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company 's financial condition, results of operations, or liquidity. Leases: In February of 2016, the FASB issued guidance to increase transparency and comparability across entities for leasing arrangements. This guidance requires lessees to recognize assets and liabilities for most leases. For lessors, this guidance modifies the lease classification criteria and the accounting for sales-type and direct financing leases. In addition, this guidance clarifies criteria for the determination of whether a contract is or contains a lease. This guidance is effective for annual and interim periods beginning after December 15, 2018. Early adoption is permitted. During 2016, the Company entered into a sale-leaseback transaction that resulted in a deferred gain of $82.5 million , with $78.1 million remaining as of June 30, 2017 . Upon adoption of this guidance, the remaining deferred gain will be recognized immediately as a cumulative-effect adjustment to equity. For additional discussion of the sale-leaseback transaction, see Note 8 " Premises, Furniture, and Equipment ." Management is evaluating the new guidance and the additional impact to the Company 's financial condition, results of operations, or liquidity. Measurement of Credit Losses on Financial Instruments: In June of 2016, the FASB issued guidance that will require entities to present financial assets measured at amortized cost at the net amount expected to be collected, considering an entity's current estimate of all expected credit losses. In addition, credit losses relating to available-for-sale debt securities will be required to be recorded through an allowance for credit losses, with changes in credit loss estimates recognized through current earnings. This guidance is effective for annual and interim periods beginning after December 15, 2019. Early adoption is permitted, but not for periods beginning before December 15, 2018. Management is evaluating the new guidance and the impact to the Company 's financial condition, results of operations, and liquidity. Classification of Certain Cash Receipts and Cash Payments: In August of 2016, the FASB issued guidance clarifying certain cash flow presentation and classification issues to reduce diversity in practice. This guidance is effective for annual and interim reporting periods beginning on or after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company 's Consolidated Statement of Cash Flows. Income Taxes: In October of 2016, the FASB issued guidance that requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Clarifying the Definition of a Business: In January of 2017, the FASB issued guidance that clarifies the definition of a business to assist entities with evaluating whether transactions should be accounted for as acquisitions or disposals of assets or businesses. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management will apply this guidance to future transactions upon adoption. Accounting for Goodwill Impairment: In January of 2017, the FASB issued guidance that simplifies the accounting for goodwill impairment for all entities. The new guidance eliminates the requirement to calculate the implied fair value of goodwill using the second step of the quantitative two-step goodwill impairment model prescribed under current accounting guidance. Under the new guidance, if a reporting unit's carrying amount exceeds its fair value, an entity will record an impairment charge based on that difference. This guidance is effective for annual and interim goodwill impairment testing dates beginning after December 15, 2019. Early adoption is permitted for annual and interim goodwill impairment testing dates after January 1, 2017. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Presentation of Defined Benefit Retirement Plan Costs: In March of 2017, the FASB issued guidance that changes how employers that sponsor defined pension and or other postretirement benefit plans present the net periodic benefit cost in the income statement. Employers will present the service cost component of net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. Other components of net periodic benefit cost will be presented separately from the line item(s) that includes the service cost. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Premium Amortization on Purchased Callable Debt Securities: In March of 2017, the FASB issued guidance that shortens the amortization period for the premium on certain purchased callable debt securities to the earliest call date. This guidance is effective for annual and interim periods beginning after December 15, 2018. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Share-based Payment Award Modifications: In May of 2017, the FASB issued guidance to reduce diversity in practice by clarifying when changes to the terms or conditions of a share-based payment award must be accounted for as a modification. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity.

Acquisitions

Acquisitions	6 Months Ended
	Jun. 30, 2017
Business Combinations [Abstract]
Acquisitions	ACQUISITIONS Completed Acquisitions Standard Bancshares, Inc. On January 6, 2017, the Company completed the acquisition of Standard Bancshares, Inc. (" Standard "), the holding company for Standard Bank and Trust Company. Pursuant to the terms of the merger agreement, on January 6, 2017, each outstanding share of Standard common stock was canceled and converted into the right to receive 0.4350 of a share of Company common stock. Based on the closing trading price of shares of Company common stock on the NASDAQ on that date of $25.34 , the value of the merger consideration per share of Standard common stock was $11.02 . Each outstanding Standard stock settled right was redeemed for cash, and each outstanding Standard stock option and each share of Standard phantom stock was canceled and terminated in exchange for the right to receive cash, in each case, pursuant to the terms of the merger agreement. This resulted in an overall transaction value of approximately $580.7 million , which consisted of 21,057,085 shares of Company common stock and $47.1 million in cash. Goodwill of $339.3 million associated with the acquisition was recorded by the Company. All operating systems were converted during the first quarter of 2017. During the second quarter of 2017, the Company updated the fair value adjustments associated with the Standard transaction. The adjustments were recognized in the current period in accordance with accounting guidance applicable to business combinations. The fair value adjustments, including goodwill, remain preliminary and may change as the Company continues to finalize the fair value of the assets and liabilities acquired. Premier Asset Management LLC On February 28, 2017, the Company completed the acquisition of Premier Asset Management LLC ("Premier"), a registered investment advisor based in Chicago, Illinois. At the close of the acquisition, the Company acquired approximately $550.0 million of trust assets under management. The fair value adjustments, including goodwill, remain preliminary and may change as the Company continues to finalize the fair value of the assets and liabilities acquired. NI Bancshares Corporation On March 8, 2016, the Company completed the acquisition of NI Bancshares Corporation (" NI Bancshares "), the holding company for The National Bank & Trust Company of Sycamore. As part of the acquisition, the Company acquired all assets and assumed all liabilities of NI Bancshares , which included ten banking offices in northern Illinois and over $700.0 million in trust assets under management. The merger consideration was a combination of Company common stock and cash, at a purchase price of $70.1 million . Goodwill of $22.2 million associated with the acquisition was recorded by the Company. The fair value adjustments associated with this transaction were finalized during the first quarter of 2017. The following table presents the assets acquired and liabilities assumed, net of the fair value adjustments, in the Standard and NI Bancshares transactions as of the acquisition date. The assets acquired and liabilities assumed, both intangible and tangible, were recorded at their estimated fair values as of the acquisition date and have been accounted for under the acquisition method of accounting. Acquisition Activity (Amounts in thousands, except share and per share data) Standard NI Bancshares January 6, 2017 March 8, 2016 Assets Cash and due from banks and interest-bearing deposits in other banks $ 102,149 $ 72,533 Securities available-for-sale 214,107 125,843 Securities held-to-maturity — 1,864 FHLB and FRB stock 3,247 1,549 Loans 1,769,655 396,181 OREO 8,424 2,863 Investment in BOLI 55,629 8,384 Goodwill 339,253 22,174 Other intangible assets 31,072 10,408 Premises, furniture, and equipment 60,207 19,636 Accrued interest receivable and other assets 56,036 16,453 Total assets $ 2,639,779 $ 677,888 Liabilities Noninterest-bearing deposits $ 675,354 $ 130,909 Interest-bearing deposits 1,348,520 464,012 Total deposits 2,023,874 594,921 Borrowed funds — 2,416 Intangible liabilities — 230 Accrued interest payable and other liabilities 35,190 10,239 Total liabilities 2,059,064 607,806 Consideration Paid Common stock (2017 - 21,057,085 shares issued at $25.34 per share, 2016 - 3,042,494 shares issued at $18.059 per share), net of issuance costs 533,590 54,896 Cash paid 47,125 15,186 Total consideration paid 580,715 70,082 $ 2,639,779 $ 677,888 Expenses related to the acquisition and integration of the transactions above totaled $1.2 million and $19.7 million during the quarter and six months ended June 30, 2017 , respectively, and are reported as a separate component within noninterest expense in the Condensed Consolidated Statements of Income. Expenses related to the acquisition and integration of the transactions above totaled $618,000 and $5.6 million during the quarter and six months ended June 30, 2016 , respectively. The acquisition of Standard was considered material to the Company's financial statements; therefore, pro forma financial data and related disclosures are included in the following tables. The unaudited pro forma combined results of operations for the quarters and six months ended June 30, 2017 and 2016 are presented as if the Standard acquisition had occurred on January 1, 2016, the first day of the Company's 2016 fiscal year. The unaudited pro forma combined results of operations are presented for illustrative purposes only and do not necessarily indicate the financial results of the combined companies had the companies actually been combined at the beginning of the period presented. Fair value adjustments included in the following table are preliminary and may be revised. The unaudited pro forma results of operations also does not consider any potential impacts of potential revenue enhancements, anticipated cost savings and expense efficiencies, or asset dispositions, among other factors. Acquisition and integration related expenses directly attributable to the Standard acquisition have been excluded from the following table and are estimated to total $27.0 million , of which $1.2 million and $18.7 million was expensed during the quarter and six months ended June 30, 2017, respectively. Unaudited Pro Forma Combined Results of Operations (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Total revenues (1) $ 162,528 $ 154,831 $ 319,285 $ 298,176 Net income 35,652 29,304 68,386 52,465 (1) Includes net interest income and total noninterest income. Acquired loans are recorded at fair value, which incorporates credit risk, at the date of acquisition. No allowance for credit losses is recorded on the acquisition date. Acquired loans are separated into (i) non-PCI and (ii) PCI loans. Non-PCI loans include loans that did not have evidence of credit deterioration since origination at the acquisition date. PCI loans include loans that had evidence of credit deterioration since origination and for which it was probable at acquisition that the Company would not collect all contractually required principal and interest payments. PCI loans are accounted for based on estimates of expected future cash flows. Expected future cash flows in excess of the fair value of loans at the purchase date ("accretable yield") are recorded as interest income over the life of the loans if the timing and amount of the expected future cash flows can be reasonably estimated. The non-accretable yield represents the difference between contractually required payments and the expected future cash flows determined at acquisition. For additional discussion regarding significant accounting policies on acquired loans see Note 1 , " Summary of Significant Accounting Policies ." The following table presents additional detail for loans acquired in the Standard transaction at the acquisition date. Standard Acquired Loans (Dollar amounts in thousands) January 6, 2017 PCI Loans Non-PCI Loans Fair value $ 125,492 $ 1,644,163 Contractually required principal and interest payments 210,891 1,938,100 Best estimate of contractual cash flows not expected to be collected (1) 57,754 100,791 Best estimate of contractual cash flows expected to be collected 153,137 1,837,309 (1) Includes interest payments not expected to be collected due to loan prepayments as well as principal and interest payments not expected to be collected due to customer default.

Securities

Securities	6 Months Ended
	Jun. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Securities	SECURITIES The significant accounting policies related to securities are presented in Note 1 , " Summary of Significant Accounting Policies " to the Consolidated Financial Statements in the Company 's 2016 10-K. A summary of the Company's securities portfolio by category and maturity is presented in the following tables. Securities Portfolio (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Amortized Cost Gross Unrealized Fair Value Amortized Cost Gross Unrealized Fair Value Gains Losses Gains Losses Securities Available-for-Sale U.S. treasury securities $ 48,568 $ 19 $ (104 ) $ 48,483 $ 48,581 $ 26 $ (66 ) $ 48,541 U.S. agency securities 174,757 599 (298 ) 175,058 183,528 519 (410 ) 183,637 Collateralized mortgage obligations ("CMOs") 1,017,896 1,086 (12,818 ) 1,006,164 1,064,130 969 (17,653 ) 1,047,446 Other mortgage-backed securities ("MBSs") 377,043 1,261 (4,644 ) 373,660 337,139 1,395 (5,879 ) 332,655 Municipal securities 262,906 2,446 (950 ) 264,402 273,319 1,245 (3,718 ) 270,846 Trust-preferred collateralized debt obligations ("CDOs") 47,740 279 (14,565 ) 33,454 47,681 261 (14,682 ) 33,260 Equity securities 7,106 154 (233 ) 7,027 3,206 147 (288 ) 3,065 Total securities available-for-sale $ 1,936,016 $ 5,844 $ (33,612 ) $ 1,908,248 $ 1,957,584 $ 4,562 $ (42,696 ) $ 1,919,450 Securities Held-to-Maturity Municipal securities $ 17,353 $ — $ (2,454 ) $ 14,899 $ 22,291 $ — $ (4,079 ) $ 18,212 Trading Securities $ 19,545 $ 17,920 Remaining Contractual Maturity of Securities (Dollar amounts in thousands) As of June 30, 2017 Available-for-Sale Held-to-Maturity Amortized Cost Fair Value Amortized Cost Fair Value One year or less $ 94,163 $ 91,946 $ 1,935 $ 1,661 After one year to five years 362,886 354,341 6,321 5,427 After five years to ten years 2,595 2,533 2,259 1,940 After ten years 74,327 72,577 6,838 5,871 Securities that do not have a single contractual maturity date 1,402,045 1,386,851 — — Total $ 1,936,016 $ 1,908,248 $ 17,353 $ 14,899 The carrying value of securities available-for-sale that were pledged to secure deposits or for other purposes as permitted or required by law totaled $1.1 billion for both June 30, 2017 and December 31, 2016 . No securities held-to-maturity were pledged as of June 30, 2017 or December 31, 2016 . During the quarters and six months ended June 30, 2017 and 2016 there were no material gross trading gains (losses). The following table presents net realized gains on securities available-for-sale for the quarters and six months ended June 30, 2017 and 2016 . Securities Available-for-Sale Gains (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Gains on sales of securities: Gross realized gains $ 284 $ 149 $ 284 $ 1,079 Gross realized losses — (126 ) — (169 ) Net realized gains on sales of securities 284 23 284 910 Non-cash impairment charges: Other-than-temporary securities impairment ("OTTI") — — — — Net realized gains $ 284 $ 23 $ 284 $ 910 Securities acquired in the Standard transaction in the first quarter of 2017 were sold shortly after the acquisition date for $210.2 million , resulting in no gains or losses as the securities were recorded at fair value upon acquisition. Accounting guidance requires that the credit portion of an OTTI charge be recognized through income. If a decline in fair value below carrying value is not attributable to credit deterioration and the Company does not intend to sell the security or believe it would not be more likely than not required to sell the security prior to recovery, the Company records the non-credit related portion of the decline in fair value in other comprehensive income. The outstanding balance of OTTI previously recognized on securities available-for-sale was $23.3 million for both June 30, 2017 and December 31, 2016 . During the quarters and six months ended June 30, 2017 and 2016 there were no additions or reductions to the balance of OTTI related to securities available-for-sale. The following table presents the aggregate amount of unrealized losses and the aggregate related fair values of securities with unrealized losses as of June 30, 2017 and December 31, 2016 . Securities in an Unrealized Loss Position (Dollar amounts in thousands) Less Than 12 Months 12 Months or Longer Total Number of Securities Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses As of June 30, 2017 Securities Available-for-Sale U.S. treasury securities 18 $ 42,442 $ 104 $ — $ — $ 42,442 $ 104 U.S. agency securities 36 68,096 245 13,235 53 81,331 298 CMOs 186 737,140 10,196 87,787 2,622 824,927 12,818 MBSs 73 287,409 4,235 21,101 409 308,510 4,644 Municipal securities 141 58,746 868 3,623 82 62,369 950 CDOs 7 — — 30,744 14,565 30,744 14,565 Equity securities 2 — — 6,778 233 6,778 233 Total 463 $ 1,193,833 $ 15,648 $ 163,268 $ 17,964 $ 1,357,101 $ 33,612 Securities Held-to-Maturity Municipal securities 11 $ — $ — $ 14,899 $ 2,454 $ 14,899 $ 2,454 As of December 31, 2016 Securities Available-for-Sale U.S. treasury securities 16 $ 33,505 $ 61 $ 3,995 $ 5 $ 37,500 $ 66 U.S. agency securities 28 62,064 364 11,814 46 73,878 410 CMOs 194 523,233 10,309 411,758 7,344 934,991 17,653 MBSs 68 221,174 4,726 77,780 1,154 298,954 5,880 Municipal securities 380 133,957 3,059 29,280 659 163,237 3,718 CDOs 7 — — 30,592 14,682 30,592 14,682 Equity securities 2 404 201 2,319 86 2,723 287 Total 695 $ 974,337 $ 18,720 $ 567,538 $ 23,976 $ 1,541,875 $ 42,696 Securities Held-to-Maturity Municipal securities 14 $ — $ — $ 18,212 $ 4,079 $ 18,212 $ 4,079 Substantially all of the Company 's CMO s and other MBSs are either backed by U.S. government-owned agencies or issued by U.S. government-sponsored enterprises. Municipal securities are issued by municipal authorities, and the majority are supported by third party insurance or some other form of credit enhancement. Management does not believe any of these securities with unrealized losses as of June 30, 2017 represent OTTI related to credit deterioration. These unrealized losses are attributed to changes in interest rates and temporary market movements. The Company does not intend to sell these securities and it is not more likely than not that the Company will be required to sell them before recovery of their amortized cost basis, which may be at maturity. The unrealized losses on CDOs as of June 30, 2017 reflect changes in market activity for these securities. Management does not believe these unrealized losses represent OTTI related to credit deterioration. In addition, the Company does not intend to sell the CDOs with unrealized losses and the Company does not believe it is more likely than not that it will be required to sell them before recovery of their amortized cost basis, which may be at maturity. Significant judgment is required to calculate the fair value of the CDOs . For a detailed discussion of the CDO valuation methodology, see Note 15 , " Fair Value ."

Loans

Loans	6 Months Ended
	Jun. 30, 2017
Loans and Leases Receivable Disclosure [Abstract]
Loans	LOANS Loans Held-for-Investment The following table presents the Company 's loans held-for-investment by class. Loan Portfolio (Dollar amounts in thousands) As of June 30, December 31, Commercial and industrial $ 3,410,748 $ 2,827,658 Agricultural 433,424 389,496 Commercial real estate: Office, retail, and industrial 1,983,802 1,581,967 Multi-family 681,032 614,052 Construction 543,892 451,540 Other commercial real estate 1,383,937 979,528 Total commercial real estate 4,592,663 3,627,087 Total corporate loans 8,436,835 6,844,241 Home equity 865,656 747,983 1-4 family mortgages 614,818 423,922 Installment 314,850 237,999 Total consumer loans 1,795,324 1,409,904 Total loans $ 10,232,159 $ 8,254,145 Deferred loan fees included in total loans $ 4,375 $ 3,838 Overdrawn demand deposits included in total loans 7,946 7,836 The increase in total loans for the quarter ended June 30, 2017 includes loans acquired in the Standard acquisition. For additional disclosure related to the Standard transaction, see Note 3 , " Acquisitions ." The Company primarily lends to community-based and mid-sized businesses, commercial real estate customers, and consumers in its markets. Within these areas, the Company diversifies its loan portfolio by loan type, industry, and borrower. It is the Company 's policy to review each prospective credit to determine the appropriateness and the adequacy of security or collateral prior to making a loan. In the event of borrower default, the Company seeks recovery in compliance with state lending laws, the Company 's lending standards, and credit monitoring and remediation procedures. A discussion of risk characteristics relevant to each portfolio segment is presented in Note 5 , "Loans" to the Consolidated Financial Statements in the Company 's 2016 10-K. Loan Sales The following table presents loan sales for the quarters and six months ended June 30, 2017 and 2016 . Loan Sales (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Corporate loan sales Proceeds from sales $ 19,569 $ 14,271 $ 34,937 $ 23,859 Less book value of loans sold 19,123 13,760 34,240 22,890 Net gains on corporate loan sales (1) 446 511 697 969 1-4 family mortgage loan sales Proceeds from sales $ 60,894 $ 53,258 116,655 92,765 Less book value of loans sold 59,461 52,089 114,059 90,769 Net gains on 1-4 family mortgage loan sales (2) 1,433 1,169 2,596 1,996 Total net gains on loan sales $ 1,879 $ 1,680 $ 3,293 $ 2,965 (1) Net gains on corporate loan sales are included in other service charges, commissions, and fees in the Condensed Consolidated Statements of Income. (2) Net gains on 1-4 family mortgage loan sales are included in mortgage banking income in the Condensed Consolidated Statements of Income. The Company retained servicing responsibilities for a portion of the 1-4 family mortgage loans sold and collects servicing fees equal to a percentage of the outstanding principal balance. For additional disclosure related to the Company's obligations resulting from the sale of certain 1-4 family mortgage loans, see Note 14 , " Commitments, Guarantees, and Contingent Liabilities ."

Acquired and Covered Loans

Acquired and Covered Loans	6 Months Ended
	Jun. 30, 2017
Acquired Loans [Abstract]
Acquired and Covered Loans	ACQUIRED AND COVERED LOANS The significant accounting policies related to acquired and covered loans, which are classified as PCI and non-PCI , are presented in Note 1 , " Summary of Significant Accounting Policies ." The following table presents the carrying amount of acquired and covered PCI and non-PCI loans as of June 30, 2017 and December 31, 2016 . Acquired and Covered Loans (1) (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 PCI Non-PCI Total PCI Non-PCI Total Acquired loans $ 161,222 $ 1,871,576 $ 2,032,798 $ 53,772 $ 613,339 $ 667,111 Covered loans 7,387 13,837 21,224 7,895 15,379 23,274 Total acquired and covered loans $ 168,609 $ 1,885,413 $ 2,054,022 $ 61,667 $ 628,718 $ 690,385 (1) Included in loans in the Consolidated Statements of Condition. The outstanding balance of PCI loans was $242.0 million and $84.8 million as of June 30, 2017 and December 31, 2016 , respectively. The increase in acquired loans compared to December 31, 2016 includes loans acquired in the Standard acquisition. For additional disclosure related to the Standard transaction, see Note 3 , " Acquisitions ." Acquired non-PCI loans that are renewed are no longer classified as acquired loans. These loans totaled $233.6 million and $117.6 million as of June 30, 2017 and December 31, 2016 , respectively. In connection with the FDIC Agreements , the Company recorded an indemnification asset. To maintain eligibility for the loss share reimbursement, the Company is required to follow certain servicing procedures as specified in the FDIC Agreements . The Company was in compliance with those requirements as of June 30, 2017 and December 31, 2016 . Rollforwards of the carrying value of the FDIC indemnification asset for the quarters and six months ended June 30, 2017 and 2016 are presented in the following table. Changes in the FDIC Indemnification Asset (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 4,220 $ 5,680 $ 4,522 $ 3,903 Amortization (302 ) (302 ) (604 ) (582 ) Change in expected reimbursements from the FDIC for changes in expected credit losses (202 ) (475 ) (530 ) (259 ) Net payments to the FDIC 202 268 530 2,109 Ending balance $ 3,918 $ 5,171 $ 3,918 $ 5,171 Changes in the accretable yield for acquired and covered PCI loans were as follows. Changes in Accretable Yield (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balances $ 41,249 $ 27,258 $ 19,385 $ 24,912 Additions — — 27,316 3,981 Accretion (3,888 ) (2,303 ) (7,843 ) (3,849 ) Other (1) 2,509 127 1,012 38 Ending balance $ 39,870 $ 25,082 $ 39,870 $ 25,082 (1) Increases represent a rise in the expected future cash flows to be collected over the remaining estimated life of the underlying portfolio. Total accretion on acquired and covered PCI and non-PCI loans for the quarter and six months ended June 30, 2017 was $8.8 million and $20.1 million , respectively, and $4.9 million and $7.4 million for the same periods in 2016 .

Past Due Loans, Allowance For C

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS	6 Months Ended
	Jun. 30, 2017
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS	PAST DUE LOANS, ALLOWANCE FOR CREDIT LOSSES, IMPAIRED LOANS, AND TDRS Past Due and Non-accrual Loans The following table presents an aging analysis of the Company 's past due loans as of June 30, 2017 and December 31, 2016 . The aging is determined without regard to accrual status. The table also presents non-performing loans, consisting of non-accrual loans (the majority of which are past due) and loans 90 days or more past due and still accruing interest, as of each balance sheet date. Aging Analysis of Past Due Loans and Non-performing Loans by Class (Dollar amounts in thousands) Aging Analysis (Accruing and Non-accrual) Non-performing Loans Current (1) 30-89 Days Past Due 90 Days or More Past Due Total Past Due Total Loans Non- accrual (2) 90 Days or More Past Due, Still Accruing Interest As of June 30, 2017 Commercial and industrial $ 3,399,763 $ 8,282 $ 2,703 $ 10,985 $ 3,410,748 $ 51,400 $ 1,550 Agricultural 432,672 379 373 752 433,424 387 — Commercial real estate: Office, retail, and industrial 1,973,608 1,847 8,347 10,194 1,983,802 15,031 — Multi-family 679,795 1,128 109 1,237 681,032 158 109 Construction 543,023 675 194 869 543,892 197 — Other commercial real estate 1,378,534 2,363 3,040 5,403 1,383,937 3,736 64 Total commercial real estate 4,574,960 6,013 11,690 17,703 4,592,663 19,122 173 Total corporate loans 8,407,395 14,674 14,766 29,440 8,436,835 70,909 1,723 Home equity 859,362 4,083 2,211 6,294 865,656 5,126 41 1-4 family mortgages 612,669 1,149 1,000 2,149 614,818 3,161 — Installment 312,132 2,423 295 2,718 314,850 — 295 Total consumer loans 1,784,163 7,655 3,506 11,161 1,795,324 8,287 336 Total loans $ 10,191,558 $ 22,329 $ 18,272 $ 40,601 $ 10,232,159 $ 79,196 $ 2,059 As of December 31, 2016 Commercial and industrial $ 2,816,442 $ 6,426 $ 4,790 $ 11,216 $ 2,827,658 $ 29,938 $ 374 Agricultural 388,596 — 900 900 389,496 181 736 Commercial real estate: Office, retail, and industrial 1,564,007 5,327 12,633 17,960 1,581,967 17,277 1,129 Multi-family 612,446 858 748 1,606 614,052 311 604 Construction 450,927 332 281 613 451,540 286 — Other commercial real estate 974,575 1,307 3,646 4,953 979,528 2,892 1,526 Total commercial real estate 3,601,955 7,824 17,308 25,132 3,627,087 20,766 3,259 Total corporate loans 6,806,993 14,250 22,998 37,248 6,844,241 50,885 4,369 Home equity 740,919 4,545 2,519 7,064 747,983 5,465 109 1-4 family mortgages 420,264 2,652 1,006 3,658 423,922 2,939 272 Installment 236,264 1,476 259 1,735 237,999 — 259 Total consumer loans 1,397,447 8,673 3,784 12,457 1,409,904 8,404 640 Total loans $ 8,204,440 $ 22,923 $ 26,782 $ 49,705 $ 8,254,145 $ 59,289 $ 5,009 (1) PCI loans with an accretable yield are considered current. (2) Includes PCI loans of $243,000 and $682,000 as of June 30, 2017 and December 31, 2016 , respectively, which no longer have an accretable yield as estimates of expected future cash flows have decreased since the acquisition due to credit deterioration. Allowance for Credit Losses The Company maintains an allowance for credit losses at a level deemed adequate by management to absorb estimated losses inherent in the existing loan portfolio. See Note 1 , " Summary of Significant Accounting Policies ," for the accounting policy for the allowance for credit losses. A rollforward of the allowance for credit losses by portfolio segment for the quarters and six months ended June 30, 2017 and 2016 is presented in the table below. Allowance for Credit Losses by Portfolio Segment (Dollar amounts in thousands) Commercial, Industrial, and Agricultural Office, Retail, and Industrial Multi- family Construction Other Commercial Real Estate Consumer Reserve for Unfunded Commitments Total Allowance for Credit Losses Quarter ended June 30, 2017 Beginning balance $ 41,786 $ 17,701 $ 2,860 $ 4,110 $ 6,922 $ 14,784 $ 1,000 $ 89,163 Charge-offs (2,957 ) — — (39 ) (307 ) (1,556 ) — (4,859 ) Recoveries 400 8 6 12 79 323 — 828 Net charge-offs (2,557 ) 8 6 (27 ) (228 ) (1,233 ) — (4,031 ) Provision for loan losses and other 7,042 (2,701 ) 53 11 785 3,049 — 8,239 Ending balance $ 46,271 $ 15,008 $ 2,919 $ 4,094 $ 7,479 $ 16,600 $ 1,000 $ 93,371 Quarter ended June 30, 2016 Beginning balance $ 37,736 $ 14,420 $ 2,547 $ 2,433 $ 6,588 $ 13,426 $ 1,225 $ 78,375 Charge-offs (2,026 ) (1,641 ) (84 ) (8 ) (879 ) (1,495 ) — (6,133 ) Recoveries 576 8 1 20 69 329 — 1,003 Net charge-offs (1,450 ) (1,633 ) (83 ) 12 (810 ) (1,166 ) — (5,130 ) Provision for loan losses and other 3,798 198 469 (206 ) 1,714 2,112 175 8,260 Ending balance $ 40,084 $ 12,985 $ 2,933 $ 2,239 $ 7,492 $ 14,372 $ 1,400 $ 81,505 Six months ended June 30, 2017 Beginning balance $ 40,709 $ 17,595 $ 3,261 $ 3,444 $ 7,739 $ 13,335 $ 1,000 $ 87,083 Charge-offs (7,031 ) (127 ) — (44 ) (715 ) (3,220 ) — (11,137 ) Recoveries 2,066 983 34 239 180 766 — 4,268 Net charge-offs (4,965 ) 856 34 195 (535 ) (2,454 ) — (6,869 ) Provision for loan losses and other 10,527 (3,443 ) (376 ) 455 275 5,719 — 13,157 Ending balance $ 46,271 $ 15,008 $ 2,919 $ 4,094 $ 7,479 $ 16,600 $ 1,000 $ 93,371 Six months ended June 30, 2016 Beginning balance $ 37,074 $ 13,124 $ 2,469 $ 1,440 $ 6,109 $ 13,414 $ 1,225 $ 74,855 Charge-offs (3,924 ) (2,165 ) (288 ) (134 ) (2,324 ) (2,487 ) — (11,322 ) Recoveries 1,078 111 26 35 220 649 — 2,119 Net charge-offs (2,846 ) (2,054 ) (262 ) (99 ) (2,104 ) (1,838 ) — (9,203 ) Provision for loan losses and other 5,856 1,915 726 898 3,487 2,796 175 15,853 Ending balance $ 40,084 $ 12,985 $ 2,933 $ 2,239 $ 7,492 $ 14,372 $ 1,400 $ 81,505 The table below provides a breakdown of loans and the related allowance for credit losses by portfolio segment as of June 30, 2017 and December 31, 2016 . Loans and Related Allowance for Credit Losses by Portfolio Segment (Dollar amounts in thousands) Loans Allowance for Credit Losses Individually Evaluated for Impairment Collectively Evaluated for Impairment PCI Total Individually Evaluated for Impairment Collectively Evaluated for Impairment PCI Total As of June 30, 2017 Commercial, industrial, and agricultural $ 50,521 $ 3,763,526 $ 30,125 $ 3,844,172 $ 4,859 $ 40,922 $ 490 $ 46,271 Commercial real estate: Office, retail, and industrial 13,781 1,951,097 18,924 1,983,802 379 12,970 1,659 15,008 Multi-family 396 666,237 14,399 681,032 — 2,833 86 2,919 Construction — 528,570 15,322 543,892 — 3,945 149 4,094 Other commercial real estate 2,174 1,314,977 66,786 1,383,937 — 6,225 1,254 7,479 Total commercial real estate 16,351 4,460,881 115,431 4,592,663 379 25,973 3,148 29,500 Total corporate loans 66,872 8,224,407 145,556 8,436,835 5,238 66,895 3,638 75,771 Consumer — 1,772,271 23,053 1,795,324 — 15,173 1,427 16,600 Reserve for unfunded commitments — — — — — 1,000 — 1,000 Total loans $ 66,872 $ 9,996,678 $ 168,609 $ 10,232,159 $ 5,238 $ 83,068 $ 5,065 $ 93,371 As of December 31, 2016 Commercial, industrial, and agricultural $ 24,645 $ 3,189,327 $ 3,182 $ 3,217,154 $ 507 $ 39,554 $ 648 $ 40,709 Commercial real estate: Office, retail, and industrial 16,287 1,553,234 12,446 1,581,967 — 16,148 1,447 17,595 Multi-family 398 601,429 12,225 614,052 — 3,059 202 3,261 Construction 34 447,058 4,448 451,540 — 3,280 164 3,444 Other commercial real estate 1,286 965,900 12,342 979,528 18 6,613 1,108 7,739 Total commercial real estate 18,005 3,567,621 41,461 3,627,087 18 29,100 2,921 32,039 Total corporate loans 42,650 6,756,948 44,643 6,844,241 525 68,654 3,569 72,748 Consumer — 1,392,880 17,024 1,409,904 — 12,210 1,125 13,335 Reserve for unfunded commitments — — — — — 1,000 — 1,000 Total loans $ 42,650 $ 8,149,828 $ 61,667 $ 8,254,145 $ 525 $ 81,864 $ 4,694 $ 87,083 Loans Individually Evaluated for Impairment The following table presents loans individually evaluated for impairment by class of loan as of June 30, 2017 and December 31, 2016 . PCI loans are excluded from this disclosure. Impaired Loans Individually Evaluated by Class (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Recorded Investment In Recorded Investment In Loans with No Specific Reserve Loans with a Specific Reserve Unpaid Principal Balance Specific Reserve Loans with No Specific Reserve Loans with a Specific Reserve Unpaid Principal Balance Specific Reserve Commercial and industrial $ 16,215 $ 34,027 $ 53,545 $ 4,859 $ 11,579 $ 13,066 $ 29,514 $ 507 Agricultural 279 — 1,629 — — — — — Commercial real estate: Office, retail, and industrial 10,125 3,656 16,966 379 16,287 — 21,057 — Multi-family 396 — 396 — 398 — 398 — Construction — — — — 34 — 34 — Other commercial real estate 2,174 — 2,271 — 1,016 270 2,141 18 Total commercial real estate 12,695 3,656 19,633 379 17,735 270 23,630 18 Total impaired loans individually evaluated for impairment $ 29,189 $ 37,683 $ 74,807 $ 5,238 $ 29,314 $ 13,336 $ 53,144 $ 525 The following table presents the average recorded investment and interest income recognized on impaired loans by class for the quarters and six months ended June 30, 2017 and 2016 . PCI loans are excluded from this disclosure. Average Recorded Investment and Interest Income Recognized on Impaired Loans by Class (Dollar amounts in thousands) Quarters Ended June 30, 2017 2016 Average Interest Income Recognized (1) Average Interest Income Recognized (1) Commercial and industrial $ 33,648 $ 342 $ 3,236 $ 12 Agricultural 697 — — — Commercial real estate: Office, retail, and industrial 13,612 169 12,712 29 Multi-family 396 — 401 — Construction — — 34 — Other commercial real estate 2,334 8 3,641 53 Total commercial real estate 16,342 177 16,788 82 Total impaired loans $ 50,687 $ 519 $ 20,024 $ 94 Six Months Ended June 30, 2017 2016 Average Interest (1) Average Interest (1) Commercial and industrial $ 30,647 $ 556 $ 3,114 $ 50 Agricultural 464 — — — Commercial real estate: Office, retail, and industrial 14,503 262 10,529 77 Multi-family 397 28 534 1 Construction 11 136 82 — Other commercial real estate 1,984 20 3,649 72 Total commercial real estate 16,895 446 14,794 150 Total impaired loans $ 48,006 $ 1,002 $ 17,908 $ 200 (1) Recorded using the cash basis of accounting. Credit Quality Indicators Corporate loans and commitments are assessed for credit risk and assigned ratings based on various characteristics, such as the borrower's cash flow, leverage, and collateral. Ratings for commercial credits are reviewed periodically. The following tables present credit quality indicators by class for corporate and consumer loans, as of June 30, 2017 and December 31, 2016 . Corporate Credit Quality Indicators by Class (Dollar amounts in thousands) Pass Special Mention (1) (4) Substandard (2) (4) Non-accrual (3) Total As of June 30, 2017 Commercial and industrial $ 3,199,001 $ 67,252 $ 93,095 $ 51,400 $ 3,410,748 Agricultural 409,969 14,464 8,604 387 433,424 Commercial real estate: Office, retail, and industrial 1,896,327 27,894 44,550 15,031 1,983,802 Multi-family 673,946 5,051 1,877 158 681,032 Construction 523,046 8,739 11,910 197 543,892 Other commercial real estate 1,338,382 21,137 20,682 3,736 1,383,937 Total commercial real estate 4,431,701 62,821 79,019 19,122 4,592,663 Total corporate loans $ 8,040,671 $ 144,537 $ 180,718 $ 70,909 $ 8,436,835 As of December 31, 2016 Commercial and industrial $ 2,638,833 $ 92,340 $ 66,547 $ 29,938 $ 2,827,658 Agricultural 366,382 17,039 5,894 181 389,496 Commercial real estate: Office, retail, and industrial 1,491,030 34,007 39,513 17,277 1,581,827 Multi-family 607,324 4,370 2,029 311 614,034 Construction 438,946 111 12,197 286 451,540 Other commercial real estate 951,115 11,808 13,544 2,892 979,359 Total commercial real estate 3,488,415 50,296 67,283 20,766 3,626,760 Total corporate loans $ 6,493,630 $ 159,675 $ 139,724 $ 50,885 $ 6,843,914 (1) Loans categorized as special mention exhibit potential weaknesses that require the close attention of management since these potential weaknesses may result in the deterioration of repayment prospects in the future. (2) Loans categorized as substandard exhibit well-defined weaknesses that may jeopardize the liquidation of the debt. These loans continue to accrue interest because they are well-secured and collection of principal and interest is expected within a reasonable time. (3) Loans categorized as non-accrual exhibit well-defined weaknesses that may jeopardize the liquidation of the debt or result in a loss if the deficiencies are not corrected. (4) Total special mention and substandard loans includes accruing TDR s of $669,000 as of June 30, 2017 and $834,000 as of December 31, 2016 . Consumer Credit Quality Indicators by Class (Dollar amounts in thousands) Performing Non-accrual Total As of June 30, 2017 Home equity $ 860,530 $ 5,126 $ 865,656 1-4 family mortgages 611,657 3,161 614,818 Installment 314,850 — 314,850 Total consumer loans $ 1,787,037 $ 8,287 $ 1,795,324 As of December 31, 2016 Home equity $ 727,618 $ 4,986 $ 732,604 1-4 family mortgages 413,415 2,939 416,354 Installment 237,999 — 237,999 Total consumer loans $ 1,379,032 $ 7,925 $ 1,386,957 TDR s TDR s are generally performed at the request of the individual borrower and may include forgiveness of principal, reduction in interest rates, changes in payments, and maturity date extensions. The table below presents TDR s by class as of June 30, 2017 and December 31, 2016 . See Note 1, "Summary of Significant Accounting Policies," for the accounting policy for TDR s. TDR s by Class (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Accruing Non-accrual (1) Total Accruing Non-accrual (1) Total Commercial and industrial $ 273 $ 891 $ 1,164 $ 281 $ 150 $ 431 Agricultural — — — — — — Commercial real estate: Office, retail, and industrial — 860 860 155 4,733 4,888 Multi-family 579 158 737 586 168 754 Construction — — — — — — Other commercial real estate 197 — 197 268 48 316 Total commercial real estate 776 1,018 1,794 1,009 4,949 5,958 Total corporate loans 1,049 1,909 2,958 1,290 5,099 6,389 Home equity 168 771 939 177 820 997 1-4 family mortgages 812 356 1,168 824 378 1,202 Installment — — — — — — Total consumer loans 980 1,127 2,107 1,001 1,198 2,199 Total loans $ 2,029 $ 3,036 $ 5,065 $ 2,291 $ 6,297 $ 8,588 (1) These TDR s are included in non-accrual loans in the preceding tables. TDR s are included in the calculation of the allowance for credit losses in the same manner as impaired loans. There were no specific reserves related to TDR s as of June 30, 2017 and as of December 31, 2016 . Accruing TDR s that do not perform in accordance with their modified terms are transferred to non-accrual. There were no material TDR s that defaulted within twelve months of the restructure date during the quarters and six months ended June 30, 2017 and 2016 . A rollforward of the carrying value of TDR s for the quarters and six months ended June 30, 2017 and 2016 is presented in the following table. TDR Rollforward (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Accruing Beginning balance $ 2,112 $ 2,702 $ 2,291 $ 2,743 Additions — — 922 — Net payments received (83 ) (28 ) (107 ) (69 ) Net transfers to non-accrual — (183 ) (1,077 ) (183 ) Ending balance 2,029 2,491 2,029 2,491 Non-accrual Beginning balance 3,112 2,268 6,297 2,324 Net payments received (75 ) (522 ) (4,225 ) (578 ) Charge-offs (1 ) (239 ) (113 ) (239 ) Net transfers from accruing — 183 1,077 183 Ending balance 3,036 1,690 3,036 1,690 Total TDRs $ 5,065 $ 4,181 $ 5,065 $ 4,181 For TDR s to be removed from TDR status in the calendar year after the restructuring, the loans must (i) have an interest rate and terms that reflect market conditions at the time of restructuring, and (ii) be in compliance with the modified terms. Loans that were not restructured at market rates and terms, that are not in compliance with the modified terms, or for which there is a concern about the future ability of the borrower to meet its obligations under the modified terms, continue to be separately reported as restructured until paid in full or charged-off. There were no material commitments to lend additional funds to borrowers with TDR s as of June 30, 2017 and December 31, 2016 .

Premises, Furniture, and Equipm

Premises, Furniture, and Equipment	6 Months Ended
	Jun. 30, 2017
Property, Plant and Equipment [Abstract]
Premises, Furniture, and Equipment	PREMISES, FURNITURE, AND EQUIPMENT The following table summarizes the Company's premises, furniture, and equipment by category. Premises, Furniture, and Equipment (Dollar amounts in thousands) As of June 30, December 31, Land $ 31,623 $ 18,304 Premises 139,137 94,369 Furniture and equipment 135,328 105,859 Total cost 306,088 218,532 Accumulated depreciation (182,075 ) (140,030 ) Net book value of premises, furniture, and equipment 124,013 78,502 Assets held-for-sale 11,732 4,075 Total premises, furniture, and equipment $ 135,745 $ 82,577 During 2016, First Midwest Bank (the "Bank") completed a sale-leaseback transaction, whereby the Bank sold to a third party for an aggregate cash purchase price of $150.3 million , 55 properties with book values totaling $58.8 million , owned and operated by the Bank as branches. The Bank concurrently entered into triple net lease agreements with certain affiliates of the third party for each of the branches sold. Subject to the right of the Bank to terminate certain of the lease agreements at the end of the eleventh year, the lease agreements have initial terms of 14 years. Each lease agreement provides the Bank with five consecutive renewal options of five years each. The sale-leaseback transaction resulted in a pre-tax gain of $88.0 million , net of transaction related expenses, with $78.1 million of deferred pre-tax gains remaining as of June 30, 2017 . As of June 30, 2017 and December 31, 2016 assets held-for-sale consisted of former branches that are no longer in operation and parcels of land previously purchased for expansion. Depreciation on premises, furniture, and equipment totaled $3.5 million and $7.0 million for the quarter and six months ended June 30, 2017 , respectively. Depreciation on premises, furniture, and equipment totaled $3.4 million and $6.6 million for the same periods in 2016 . Operating Leases As of June 30, 2017 , the Company was obligated to utilize certain premises and equipment under certain non-cancelable operating leases, which expire at various dates through the year ending December 31, 2033 . Many of these leases contain renewal options and certain leases provide options to purchase the leased property during or at the expiration of the lease period at specific prices. Some leases contain escalation clauses calling for rentals to be adjusted for increased real estate taxes and other operating expenses or proportionately adjusted for increases in consumer or other price indices. The following summary reflects the future minimum payments by year required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of June 30, 2017 . Future Minimum Operating Lease Payments (Dollar amounts in thousands) Total One year or less $ 18,383 After one year to two years 16,751 After two years to three years 16,606 After three years to four years 16,268 After four years to five years 16,119 After five years 120,356 Total minimum lease payments $ 204,483 As of June 30, 2017 , deferred pre-tax gains of $78.1 million related to the sale-lease back transaction will be accreted as a reduction to lease expense in other expenses on the Condensed Consolidated Statements of Income on a straight-line basis over the initial terms of the leases. The Company assumed certain operating leases related to various branches in previous acquisitions. An intangible liability is recorded when the cash flows of a lease exceeds its fair market value. This intangible liability will be accreted into income as a reduction to net occupancy and equipment expense using the straight-line method over the initial term of each lease, which expire between 2018 and 2030. The intangible liability is included in accrued interest and other liabilities in the Consolidated Statements of Financial Condition. The following table presents the remaining scheduled accretion of the intangible liability by year. Scheduled Accretion of Operating Lease Intangible (Dollar amounts in thousands) Total One year or less $ 1,095 After one year to two years 791 After two years to three years 648 After three years to four years 648 After four years to five years 648 After five years 3,673 Total accretion $ 7,503 The following table presents net operating lease expense for the quarters and six months ended June 30, 2017 and 2016 . Net Operating Lease Expense (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Lease expense charged to operations $ 4,721 $ 1,773 $ 9,280 $ 3,500 Accretion of operating lease intangible (1) (295 ) (295 ) (590 ) (581 ) Accretion of deferred gain on sale-leaseback transaction (1) (1,473 ) — (2,946 ) — Rental income from premises leased to others (1) (169 ) (128 ) (350 ) (286 ) Net operating lease expense $ 2,784 $ 1,350 $ 5,394 $ 2,633 (1) Included as reductions to net occupancy and equipment expense in the Condensed Consolidated Statements of Income.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	6 Months Ended
	Jun. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS The Company's annual goodwill impairment test was performed as of October 1, 2016. It was determined that no impairment existed as of that date or as of June 30, 2017 . For a discussion of the accounting policies for goodwill and other intangible assets, see Note 1 , " Summary of Significant Accounting Policies " to the Consolidated Financial Statements in the Company 's 2016 10-K. The following table presents changes in the carrying amount of goodwill for the quarters and six months ended June 30, 2017 and 2016 . Changes in the Carrying Amount of Goodwill (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 691,572 $ 339,768 $ 340,879 $ 319,007 Acquisitions (45 ) 1,745 350,648 22,506 Ending balance $ 691,527 $ 341,513 $ 691,527 $ 341,513 The decrease in goodwill for the quarter ended June 30, 2017 resulted from measurement period adjustments associated with the Standard transaction. The increase for the six months ended June 30, 2017 resulted from the Standard and Premier acquisitions and measurement period adjustments related to finalizing the fair values of the assets acquired and liabilities assumed in the NI Bancshares acquisition. During the quarter and six months ended June 30, 2016 , the increase in goodwill resulted from the NI Bancshares acquisition. The Company's other intangible assets are core deposit intangibles and trust department customer relationship intangibles, which are being amortized over their estimated useful lives. Other intangible assets are subject to impairment testing when events or circumstances indicate that its carrying amount may not be recoverable. The increase in other intangible assets for the six months ended June 30, 2017 resulted from the Standard and Premier acquisitions. The increase in other intangible assets for the six months ended June 30, 2016 resulted from the NI Bancshares acquisition. During the quarters ended June 30, 2017 and June 30, 2016 there were no events or circumstances to indicate impairment. Other Intangible Assets (Dollar amounts in thousands) Six Months Ended June 30, 2017 2016 Gross Accumulated Amortization Net Gross Accumulated Amortization Net Beginning balance $ 58,959 $ 32,962 $ 25,997 $ 48,550 $ 28,280 $ 20,270 Additions 39,017 — 39,017 10,409 — 10,409 Amortization expense — 4,128 (4,128 ) — 2,230 (2,230 ) Ending balance $ 97,976 $ 37,090 $ 60,886 $ 58,959 $ 30,510 $ 28,449 Scheduled Amortization of Other Intangible Assets (Dollar amounts in thousands) Total Year Ending June 30, 2018 $ 7,332 2019 7,086 2020 7,055 2021 6,986 2022 6,908 2023 and thereafter 25,519 Total $ 60,886

Deposits

Deposits	6 Months Ended
	Jun. 30, 2017
Deposits [Abstract]
Deposits	DEPOSITS The following table presents the Company's deposits by type. Summary of Deposits (Dollar amounts in thousands) As of June 30, December 31, Demand deposits $ 3,525,905 $ 2,766,748 Savings deposits 2,059,833 1,615,833 NOW accounts 1,970,036 1,675,421 Money market deposits 1,905,402 1,577,316 Time deposits less than $100,000 894,530 755,558 Time deposits greater than $100,000 644,014 437,727 Total deposits $ 10,999,720 $ 8,828,603 The increase in total deposits for the six months ended June 30, 2017 includes deposits assumed in the Standard acquisition. For additional disclosure related to the Standard transaction, see Note 3 , " Acquisitions ."

Material Transactions Affecting

Material Transactions Affecting Stockholders' Equity	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Material Transactions Affecting Stockholders' Equity	MATERIAL TRANSACTIONS AFFECTING STOCKHOLDERS' EQUITY On May 17, 2017 , the Company's stockholders approved and adopted an amendment to the Company's Restated Certificate of Incorporation. The amendment increased the Company's authorized common stock by 100,000,000 shares. Following this amendment, the Company is now authorized to issue a total of 251,000,000 shares, including 1,000,000 shares of Preferred Stock, without a par value, and 250,000,000 shares of Common Stock, $0.01 par value per share.

Earnings Per Common Share

Earnings Per Common Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Common Share	EARNINGS PER COMMON SHARE The table below displays the calculation of basic and diluted earnings per common share (" EPS "). Basic and Diluted EPS (Amounts in thousands, except per share data) Quarters Ended Six Months Ended 2017 2016 2017 2016 Net income $ 34,950 $ 25,267 $ 57,805 $ 43,229 Net income applicable to non-vested restricted shares (336 ) (290 ) (570 ) (502 ) Net income applicable to common shares $ 34,614 $ 24,977 $ 57,235 $ 42,727 Weighted-average common shares outstanding: Weighted-average common shares outstanding (basic) 101,743 80,383 101,081 79,182 Dilutive effect of common stock equivalents 20 13 20 12 Weighted-average diluted common shares outstanding 101,763 80,396 101,101 79,194 Basic EPS $ 0.34 $ 0.31 $ 0.57 $ 0.54 Diluted EPS $ 0.34 $ 0.31 $ 0.57 $ 0.54 Anti-dilutive shares not included in the computation of diluted EPS (1) 195 469 269 539 (1) This amount represents outstanding stock options for which the exercise price is greater than the average market price of the Company's common stock.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	6 Months Ended
	Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES In the ordinary course of business, the Company enters into derivative transactions as part of its overall interest rate risk management strategy. The significant accounting policies related to derivative instruments and hedging activities are presented in Note 1, "Summary of Significant Accounting Policies." Fair Value Hedges The Company hedges the fair value of fixed rate commercial real estate loans using interest rate swaps through which the Company pays fixed amounts and receives variable amounts. These derivative contracts are designated as fair value hedges. Fair Value Hedges (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Gross notional amount outstanding $ 5,708 $ 5,958 Derivative liability fair value (186 ) (282 ) Weighted-average interest rate received 3.08 % 2.63 % Weighted-average interest rate paid 5.96 % 5.96 % Weighted-average maturity (in years) 1.35 1.84 Fair value of derivative (1) $ 197 $ 296 (1) This amount represents the fair value if credit risk related contingent features were triggered. Hedge ineffectiveness is recognized in other noninterest income in the Condensed Consolidated Statements of Income. For the quarters and six months ended June 30, 2017 and 2016 , gains or losses related to fair value hedge ineffectiveness were not material. Cash Flow Hedges As of June 30, 2017 , the Company hedged $980.0 million of certain corporate variable rate loans using interest rate swaps through which the Company receives fixed amounts and pays variable amounts. The Company also hedged $980.0 million of borrowed funds using forward starting interest rate swaps through which the Company receives variable amounts and pays fixed amounts. These transactions allow the Company to add stability to net interest income and manage its exposure to interest rate movements. Forward starting interest rate swaps totaling $415.0 million began on various dates between June of 2015 and February of 2017, and mature between June of 2019 and February of 2020. The remaining forward starting interest rate swaps totaling $565.0 million begin at various dates between February of 2018 and February of 2020 and mature between February of 2020 and April of 2022. The weighted-average fixed interest rate to be paid on these interest rate swaps that have not yet begun was 1.96% as of June 30, 2017 . These derivative contracts are designated as cash flow hedges. Cash Flow Hedges (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Gross notional amount outstanding $ 1,960,000 $ 1,470,000 Derivative asset fair value 3,528 5,402 Derivative liability fair value (7,627 ) (7,390 ) Weighted-average interest rate received 1.51 % 1.37 % Weighted-average interest rate paid 1.40 % 1.11 % Weighted-average maturity (in years) 2.75 2.83 The effective portion of gains or losses on cash flow hedges is recorded in accumulated other comprehensive loss on an after-tax basis and is subsequently reclassified to interest income or expense in the period that the forecasted hedged item impacts earnings. Hedge effectiveness is determined using a regression analysis at the inception of the hedge relationship and on an ongoing basis. For the quarters and six months ended June 30, 2017 and 2016, there were no material gains or losses related to cash flow hedge ineffectiveness. As of June 30, 2017 , the Company estimates that $303,000 will be reclassified from accumulated other comprehensive loss as a decrease to interest income over the next twelve months. Other Derivative Instruments The Company also enters into derivative transactions through capital market products with its commercial customers and simultaneously enters into an offsetting interest rate derivative transaction with third-parties. This transaction allows the Company's customers to effectively convert a variable rate loan into a fixed rate loan. Due to the offsetting nature of these transactions, the Company does not apply hedge accounting treatment. The Company's credit exposure on these derivative transactions results primarily from counterparty credit risk. The credit valuation adjustment (" CVA ") is a fair value adjustment to the derivative to account for this risk. As of June 30, 2017 and December 31, 2016 , the Company's credit exposure was fully secured by the underlying collateral on customer loans and mitigated through netting arrangements with third-parties, therefore, no CVA was recorded. Capital market products income related to commercial customer derivative instruments of $2.2 million and $3.6 million were recorded in noninterest income for the quarters and six months ended June 30, 2017 , respectively. There were $2.1 million and $5.3 million of capital market products income recorded for quarters and six months ended June 30, 2016 , respectively. Other Derivative Instruments (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Gross notional amount outstanding $ 2,252,704 $ 1,656,612 Derivative asset fair value 17,370 13,478 Derivative liability fair value (15,347 ) (13,478 ) Fair value of derivative (1) 15,605 13,753 (1) This amount represents the fair value if credit risk related contingent features were triggered. The Company occasionally enters into risk participation agreements with counterparty banks to transfer or assume a portion of the credit risk related to customer transactions. The amounts of these instruments were not material for any periods presented. The Company had no other derivative instruments as of June 30, 2017 and December 31, 2016 . The Company does not enter into derivative transactions for purely speculative purposes. Credit Risk Derivative instruments are inherently subject to credit risk, which represents the Company's risk of loss when the counterparty to a derivative contract fails to perform according to the terms of the agreement. Credit risk is managed by limiting and collateralizing the aggregate amount of net unrealized losses by transaction, monitoring the size and the maturity structure of the derivatives, and applying uniform credit standards. Company policy establishes limits on credit exposure to any single counterparty. In addition, the Company established bilateral collateral agreements with derivative counterparties that provide for exchanges of marketable securities or cash to collateralize either party's net losses above a stated minimum threshold. As of June 30, 2017 and December 31, 2016 , these collateral agreements covered 100% of the fair value of the Company's outstanding fair value hedges. Derivative assets and liabilities are presented gross, rather than net, of pledged collateral amounts. Certain derivative instruments are subject to master netting agreements with counterparties. The Company records these transactions at their gross fair values and does not offset derivative assets and liabilities in the Consolidated Statements of Financial Condition. The following table presents the fair value of the Company's derivatives and offsetting positions as of June 30, 2017 and December 31, 2016 . Fair Value of Offsetting Derivatives (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Assets Liabilities Assets Liabilities Gross amounts recognized $ 20,898 $ 23,160 $ 18,880 $ 21,150 Less: amounts offset in the Consolidated Statements of Financial Condition — — — — Net amount presented in the Consolidated Statements of Financial Condition (1) 20,898 23,160 18,880 21,150 Gross amounts not offset in the Consolidated Statements of Financial Condition: Offsetting derivative positions (8,646 ) (8,646 ) (10,889 ) (10,889 ) Cash collateral pledged — (14,514 ) — (10,261 ) Net credit exposure $ 12,252 $ — $ 7,991 $ — (1) Included in other assets or other liabilities in the Consolidated Statements of Financial Condition. As of June 30, 2017 and December 31, 2016 , the Company's derivative instruments generally contained provisions that require the Company's debt to remain above a certain credit rating by each of the major credit rating agencies or that the Company maintain certain capital levels. If the Company's debt were to fall below that credit rating or the Company's capital were to fall below the required levels, it would be in violation of those provisions, and the counterparties to the derivative instruments could terminate the swap transaction and demand cash settlement of the derivative instrument in an amount equal to the derivative liability fair value. As of June 30, 2017 and December 31, 2016 the Company was in compliance with these provisions.

Commitments, Guarantees, and Co

Commitments, Guarantees, and Contingent Liabilities	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments, Guarantees, and Contingent Liabilities	COMMITMENTS, GUARANTEES, AND CONTINGENT LIABILITIES Credit Commitments and Guarantees In the normal course of business, the Company enters into a variety of financial instruments with off-balance sheet risk to meet the financing needs of its customers and to conduct lending activities, including commitments to extend credit and standby and commercial letters of credit. These instruments involve elements of credit and interest rate risk in excess of the amount recognized in the Consolidated Statements of Financial Condition. Contractual or Notional Amounts of Financial Instruments (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Commitments to extend credit: Commercial, industrial, and agricultural $ 1,750,477 $ 1,522,152 Commercial real estate 347,330 397,423 Home equity 508,295 426,384 Other commitments (1) 248,320 214,943 Total commitments to extend credit $ 2,854,422 $ 2,560,902 Letters of credit $ 137,913 $ 100,430 Recourse on assets sold: Unpaid principal balance of loans sold $ 185,182 $ 187,158 Carrying value of recourse obligation (2) 153 142 (1) Other commitments includes installment and overdraft protection program commitments. (2) Included in other liabilities in the Consolidated Statements of Financial Condition. Commitments to extend credit are agreements to lend funds to a customer, subject to contractual terms and covenants. Commitments generally have fixed expiration dates or other termination clauses, variable interest rates, and fee requirements, when applicable. Since many of the commitments are expected to expire without being drawn, the total commitment amounts do not necessarily represent future cash flow requirements. In the event of a customer's non-performance, the Company's credit loss exposure is equal to the contractual amount of the commitments. The credit risk is essentially the same as extending loans to customers. The Company uses the same credit policies for credit commitments as its loans and minimizes exposure to credit loss through various collateral requirements. Letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. Letters of credit generally are contingent on the failure of the customer to perform according to the terms of the contract with the third-party and are often issued in favor of a municipality where construction is taking place to ensure the borrower adequately completes the construction. Commercial letters of credit are issued to facilitate transactions between a customer and a third party based on agreed upon terms. The maximum potential future payments guaranteed by the Company under letters of credit arrangements are equal to the contractual amount of the commitment. If a commitment is funded, the Company may seek recourse through the liquidation of the underlying collateral, including real estate, production plants and property, marketable securities, or receipt of cash. As a result of the sale of certain 1-4 family mortgage loans, the Company is contractually obligated to repurchase any non-performing loans or loans that do not meet underwriting requirements at recorded value. In accordance with the sales agreements, there is no limitation to the maximum potential future payments or expiration of the Company's recourse obligation. There were no material loan repurchases during the quarters and six months ended June 30, 2017 and 2016 . Legal Proceedings In the ordinary course of business, there were certain legal proceedings pending against the Company and its subsidiaries at June 30, 2017 . While the outcome of any legal proceeding is inherently uncertain, based on information currently available, the Company's management does not expect that any liabilities arising from pending legal matters will have a material adverse effect on the Company's financial position, results of operations, or cash flows.

Fair Value

Fair Value	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value	FAIR VALUE Fair value represents the amount expected to be received to sell an asset or paid to transfer a liability in its principal or most advantageous market in an orderly transaction between market participants at the measurement date. In accordance with fair value accounting guidance, the Company measures, records, and reports various types of assets and liabilities at fair value on either a recurring or non-recurring basis in the Consolidated Statements of Financial Condition. Those assets and liabilities are presented below in the sections titled "Assets and Liabilities Required to be Measured at Fair Value on a Recurring Basis" and "Assets and Liabilities Required to be Measured at Fair Value on a Non-Recurring Basis." Other assets and liabilities are not required to be measured at fair value in the Consolidated Statements of Financial Condition, but must be disclosed at fair value. See the "Fair Value Measurements of Other Financial Instruments" section of this note. Any aggregation of the estimated fair values presented in this note does not represent the value of the Company. Depending on the nature of the asset or liability, the Company uses various valuation methodologies and assumptions to estimate fair value. GAAP provides a three-tiered fair value hierarchy based on the inputs used to measure fair value. The hierarchy is defined as follows: • Level 1 - Quoted prices in active markets for identical assets or liabilities. • Level 2 - Observable inputs other than level 1 prices, such as quoted prices for similar instruments, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data. • Level 3 - Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. These inputs require significant management judgment or estimation, some of which use model-based techniques and may be internally developed. Assets and liabilities are assigned to a level within the fair value hierarchy based on the lowest level of significant input used to measure fair value. Assets and liabilities may change levels within the fair value hierarchy due to market conditions or other circumstances. Those transfers are recognized on the date of the event that prompted the transfer. There were no transfers of assets or liabilities required to be measured at fair value on a recurring basis between levels of the fair value hierarchy during the periods presented. Assets and Liabilities Required to be Measured at Fair Value on a Recurring Basis The following table provides the fair value for assets and liabilities required to be measured at fair value on a recurring basis in the Consolidated Statements of Financial Condition by level in the fair value hierarchy. Recurring Fair Value Measurements (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets: Trading securities: Money market funds $ 1,717 $ — $ — $ 1,645 $ — $ — Mutual funds 17,828 — — 16,275 — — Total trading securities 19,545 — — 17,920 — — Securities available-for-sale: U.S. treasury securities 48,483 — — 48,541 — — U.S. agency securities — 175,058 — — 183,637 — CMOs — 1,006,164 — — 1,047,446 — MBSs — 373,660 — — 332,655 — Municipal securities — 264,402 — — 270,846 — CDOs — — 33,454 — — 33,260 Equity securities — 7,027 — — 3,065 — Total securities available-for-sale 48,483 1,826,311 33,454 48,541 1,837,649 33,260 Mortgage servicing rights ("MSRs") (1) — — 5,925 6,120 Derivative assets (1) — 20,898 — — 18,880 — Liabilities: Derivative liabilities (2) $ — $ 23,160 $ — $ — $ 21,150 $ — (1) Included in other assets in the Consolidated Statements of Financial Condition. (2) Included in other liabilities in the Consolidated Statements of Financial Condition. The following sections describe the specific valuation techniques and inputs used to measure financial assets and liabilities at fair value. Trading Securities The Company's trading securities consist of diversified investment securities held in a grantor trust and are invested in money market and mutual funds. The fair value of these money market and mutual funds is based on quoted market prices in active exchange markets and is classified in level 1 of the fair value hierarchy. Securities Available-for-Sale The Company's securities available-for-sale are primarily fixed income instruments that are not quoted on an exchange, but may be traded in active markets. The fair values for these securities are based on quoted prices in active markets or market prices for similar securities obtained from external pricing services or dealer market participants and are classified in level 2 of the fair value hierarchy. The fair value of U.S. treasury securities is based on quoted market prices in active exchange markets and is classified in level 1 of the fair value hierarchy. Quarterly, the Company evaluates the methodologies used by its external pricing services to estimate the fair value of these securities to determine whether the valuations represent an exit price in the Company's principal markets. CDOs are classified in level 3 of the fair value hierarchy. The Company estimates the fair values for each CDO using discounted cash flow analyses with the assistance of a structured credit valuation firm. This methodology is based on credit analysis and historical financial data for each of the issuers underlying the CDOs (the "Issuers"). These estimates are highly subjective and sensitive to several significant, unobservable inputs. The cash flows for each Issuer are then discounted to present values using LIBOR plus an adjustment to reflect the impact of market factors. Finally, the discounted cash flows for each Issuer are aggregated to derive the estimated fair value for the specific CDO . The following table presents the ranges of significant, unobservable inputs calculated using the weighted-average of the Issuers used by the Company as of June 30, 2017 and December 31, 2016. Significant Unobservable Inputs Used in the Valuation of CDOs As of June 30, 2017 December 31, 2016 Probability of prepayment 0.0 % - 10.9% 0.0 % - 10.9% Probability of default 15.6 % - 44.1% 16.7 % - 46.8% Loss given default 93.3 % - 99.2% 93.3 % - 98.9% Probability of deferral cure 0.0 % - 100.0% 7.6 % - 100.0% Most Issuers have the right to prepay the securities on the fifth anniversary of issuance and under other limited circumstances. To estimate prepayments, a credit analysis of each Issuer is performed to estimate its ability and likelihood to fund a prepayment. If a prepayment occurs, the Company receives cash equal to the par value for the portion of the CDO associated with that Issuer. The likelihood that an Issuer who is currently deferring payment on the securities will pay all deferred amounts and remain current thereafter is based on an analysis of the Issuer's asset quality, leverage ratios, and other measures of financial viability. The impact of changes in these key inputs could result in a significantly higher or lower fair value measurement for each CDO . The timing of the default, the magnitude of the default, and the timing and magnitude of the cure probability are directly interrelated. Defaults that occur sooner and/or are greater than anticipated have a negative impact on the valuation. In addition, a high cure probability assumption has a positive effect on the fair value, and, if a cure event takes place sooner than anticipated, the impact on the valuation is also favorable. Management monitors the valuation results of each CDO on a quarterly basis, which includes an analysis of historical pricing trends for these types of securities, overall economic conditions (such as tracking LIBOR curves), and the performance of the Issuers' industries. Annually, management validates significant assumptions by reviewing detailed back-testing performed by the structured credit valuation firm. A rollforward of the carrying value of CDOs for the quarters and six months ended June 30, 2017 and 2016 is presented in the following table. Carrying Value of CDOs (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 33,436 $ 30,757 $ 33,260 $ 31,529 Change in other comprehensive income (1) 6 (244 ) 135 (1,030 ) Other 12 (82 ) 59 (68 ) Ending balance $ 33,454 $ 30,431 $ 33,454 $ 30,431 (1) Included in unrealized holding gains in the Consolidated Statements of Comprehensive Income. MSR s The Company services loans for others totaling $626.5 million as of June 30, 2017 and $640.5 million as of December 31, 2016 . These loans are owned by third parties and are not included in the Consolidated Statements of Financial Condition. The Company determines the fair value of MSR s by estimating the present value of expected future cash flows associated with the mortgage loans being serviced and classifies them in level 3 of the fair value hierarchy. The following table presents the ranges of significant, unobservable inputs used by the Company to determine the fair value of MSR s as of June 30, 2017 and December 31, 2016 . Significant Unobservable Inputs Used in the Valuation of MSR s As of June 30, 2017 December 31, 2016 Prepayment speed 8.8 % - 25.3% 7.7 % - 22.8% Maturity (months) 8 - 92 12 - 103 Discount rate 9.5 % - 13.0% 9.5 % - 13.0% The impact of changes in these key inputs could result in a significantly higher or lower fair value measurement for MSR s. Significant increases in expected prepayment speeds and discount rates have negative impacts on the valuation. Higher maturity assumptions have a favorable effect on the estimated fair value. A rollforward of the carrying value of MSR s for the quarters and six months ended June 30, 2017 and 2016 is presented in the following table. Carrying Value of MSR s (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 6,245 $ 5,022 $ 6,120 $ 1,853 Additions from acquisition — — — 3,092 New MSRs 205 162 361 347 Total gains (losses) included in earnings (1) : Changes in valuation inputs and assumptions (260 ) (132 ) (88 ) (172 ) Other changes in fair value (2) (265 ) (114 ) (468 ) (182 ) Ending balance $ 5,925 $ 4,938 $ 5,925 $ 4,938 Contractual servicing fees earned (1) $ 384 $ 366 $ 779 $ 549 (1) Included in mortgage banking income in the Condensed Consolidated Statements of Income and related to assets held as of June 30, 2017 and 2016 . (2) Primarily represents changes in expected future cash flows due to payoffs and paydowns. Derivative Assets and Derivative Liabilities The Company enters into interest rate swaps and derivative transactions with commercial customers. These derivative transactions are executed in the dealer market, and pricing is based on market quotes obtained from the counterparties. The market quotes were developed using market observable inputs, which primarily include LIBOR. Therefore, derivatives are classified in level 2 of the fair value hierarchy. For its derivative assets and liabilities, the Company also considers non-performance risk, including the likelihood of default by itself and its counterparties, when evaluating whether the market quotes from the counterparty are representative of an exit price. Assets and Liabilities Required to be Measured at Fair Value on a Non-Recurring Basis The following table provides the fair value for each class of assets and liabilities required to be measured at fair value on a non-recurring basis in the Consolidated Statements of Financial Condition by level in the fair value hierarchy. Non-Recurring Fair Value Measurements (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Collateral-dependent impaired loans (1) $ — $ — $ 40,698 $ — $ — $ 22,019 OREO (2) — — 6,835 — — 8,624 Loans held-for-sale (3) — — 16,922 — — 10,484 Assets held-for-sale (4) — — 11,732 — — 4,075 (1) Includes impaired loans with charge-offs and impaired loans with a specific reserve during the periods presented. (2) Includes OREO with fair value adjustments subsequent to initial transfer that occurred during the periods presented. (3) Included in other assets in the Consolidated Statements of Financial Condition. (4) Included in premises, furniture, and equipment in the Consolidated Statements of Financial Condition. Collateral-Dependent Impaired Loans Certain collateral-dependent impaired loans are subject to fair value adjustments to reflect the difference between the carrying value of the loan and the value of the underlying collateral. The fair values of collateral-dependent impaired loans are primarily determined by current appraised values of the underlying collateral. Based on the age and/or type, appraisals may be adjusted in the range of 0% to 15% . In certain cases, an internal valuation may be used when the underlying collateral is located in areas where comparable sales data is limited or unavailable. Accordingly, collateral-dependent impaired loans are classified in level 3 of the fair value hierarchy. Collateral-dependent impaired loans for which the fair value is greater than the recorded investment are not measured at fair value in the Consolidated Statements of Financial Condition and are not included in this disclosure. OREO The fair value of OREO is measured using the current appraised value of the properties. In certain circumstances, a current appraisal may not be available or may not represent an accurate measurement of the property's fair value due to outdated market information or other factors. In these cases, the fair value is determined based on the lower of the (i) most recent appraised value, (ii) broker price opinion, (iii) current listing price, or (iv) signed sales contract. Given these valuation methods, OREO is classified in level 3 of the fair value hierarchy. Loans Held-for-Sale As of June 30, 2017 , loans held-for-sale consists of 1-4 family mortgage loans, which were originated with the intent to sell. These loans were recorded in the held-for-sale category at the contract price and, accordingly, are classified in level 3 of the fair value hierarchy. As of December 31, 2016 , loans held-for-sale consists of 1-4 family mortgage loans, which were originated with the intent to sell, and a corporate loan. Assets Held-for-Sale Assets held-for-sale as of June 30, 2017 and December 31, 2016 consists of former branches that are no longer in operation and parcels of land previously purchased for expansion. These properties are being actively marketed and were transferred into the held-for-sale category at their fair value as determined by current appraisals. Based on these valuation methods, they are classified in level 3 of the fair value hierarchy. Financial Instruments Not Required to be Measured at Fair Value For certain financial instruments that are not required to be measured at fair value in the Consolidated Statements of Financial Condition, the Company must disclose the estimated fair values and the level within the fair value hierarchy as shown in the following table. Fair Value Measurements of Other Financial Instruments (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Fair Value Hierarchy Level Carrying Amount Fair Value Carrying Amount Fair Value Assets: Cash and due from banks 1 $ 181,171 $ 181,171 $ 155,055 $ 155,055 Interest-bearing deposits in other banks 2 103,181 103,181 107,093 107,093 Securities held-to-maturity 2 17,353 14,899 22,291 18,212 FHLB and FRB stock 2 66,333 66,333 59,131 59,131 Loans 3 10,143,706 9,905,748 8,172,584 7,973,845 Investment in BOLI 3 278,353 278,353 219,746 219,746 Accrued interest receivable 3 39,766 39,766 34,384 34,384 Other interest-earning assets 3 454 454 834 834 Liabilities: Deposits 2 $ 10,999,720 $ 10,989,384 $ 8,828,603 $ 8,820,572 Borrowed funds 2 639,333 639,333 879,008 879,008 Senior and subordinated debt 2 194,886 205,757 194,603 197,888 Accrued interest payable 2 4,470 4,470 3,416 3,416 Management uses various methodologies and assumptions to determine the estimated fair values of the financial instruments in the table above. The fair value estimates are made at a discrete point in time based on relevant market information and consider management's judgments regarding future expected economic conditions, loss experience, and specific risk characteristics of the financial instruments. Short-Term Financial Assets and Liabilities - For financial instruments with a shorter-term or with no stated maturity, prevailing market rates, and limited credit risk, the carrying amounts approximate fair value. Those financial instruments include cash and due from banks, interest-bearing deposits in other banks, accrued interest receivable, and accrued interest payable. Securities Held-to-Maturity - The fair value of securities held-to-maturity is estimated using the present value of expected future cash flows of the remaining maturities of the securities. FHLB and FRB Stock - The carrying amounts approximate fair value as the stock is non-marketable. Loans - Loans includes the FDIC indemnification asset and net loans, which consists of loans held-for-investment, acquired loans, and the allowance for loan losses. The fair value of loans is estimated using the present value of the expected future cash flows of the remaining maturities of the loans. Prepayment assumptions that consider the Company's historical experience and current economic and lending conditions were included. The discount rate was based on the LIBOR yield curve with adjustments for liquidity and credit risk inherent in the loans. Investment in BOLI - The fair value of BOLI approximates the carrying amount as both are based on each policy's respective cash surrender value ("CSV"), which is the amount the Company would receive from the liquidation of these investments. The CSV is derived from monthly reports provided by the managing brokers and is determined using the Company 's initial insurance premium and earnings of the underlying assets, offset by management fees. Other Interest-Earning Assets - The fair value of other interest-earning assets is estimated using the present value of the expected future cash flows of the remaining maturities of the assets. Deposits - The fair values disclosed for demand deposits, savings deposits, NOW accounts, and money market deposits are equal to the amount payable on demand at the reporting date (i.e., their carrying amounts). The fair value for fixed-rate time deposits was estimated using the expected future cash flows discounted based on the LIBOR yield curve, plus or minus the spread associated with current pricing. Borrowed Funds - The fair value of FHLB advances is estimated by discounting the agreements based on maturities using the rates currently offered for FHLB advances of similar remaining maturities adjusted for prepayment penalties that would be incurred if the borrowings were paid off on the measurement date. The carrying amounts of securities sold under agreements to repurchase approximate their fair value due to their short-term nature. Senior and Subordinated Debt - The fair values of senior and subordinated notes are estimated based on quoted market prices of similar instruments. The fair values of junior subordinated debentures are estimated based on quoted market prices of comparable securities when available, or by discounting the expected future cash flows at market interest rates. Commitments to Extend Credit and Letters of Credit - The Company estimated the fair value of lending commitments outstanding to be immaterial based on (i) the limited interest rate exposure of the commitments outstanding due to their variable nature, (ii) the short-term nature of the commitment periods, (iii) termination clauses provided in the agreements, and (iv) the market rate of fees charged.

Summary of Significant Accoun24

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation – The accompanying unaudited condensed consolidated interim financial statements ("consolidated financial statements") of First Midwest Bancorp, Inc. (the " Company "), a Delaware corporation, were prepared in accordance with the rules and regulations of the Securities and Exchange Commission (" SEC ") for quarterly reports on Form 10-Q and reflect all adjustments that management deems necessary for the fair presentation of the financial position and results of operations for the periods presented. The results of operations for the quarter and six months ended June 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 . The accounting and reporting policies of the Company and its subsidiaries conform to U.S. generally accepted accounting principles (" GAAP ") and general practices within the banking industry. The accompanying consolidated financial statements do not include certain information and note disclosures required by GAAP for complete annual financial statements. Therefore, these financial statements should be read in conjunction with the Company 's 2016 Annual Report on Form 10-K (" 2016 10-K"). The Company uses the accrual basis of accounting for financial reporting purposes.
Reclassification	Certain reclassifications were made to prior year amounts to conform to the current year presentation.
Use of Estimates	Use of Estimates – The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Although these estimates and assumptions are based on the best available information, actual results could differ from those estimates.
Principles of Consolidation	Principles of Consolidation – The accompanying consolidated financial statements include the financial position and results of operations of the Company and its subsidiaries after elimination of all significant intercompany accounts and transactions. Assets held in a fiduciary or agency capacity are not assets of the Company or its subsidiaries and are not included in the consolidated financial statements.
Business Combinations	Business Combinations – Business combinations are accounted for under the acquisition method of accounting. Assets acquired and liabilities assumed are recorded at their estimated fair values as of the date of acquisition, with any excess of the purchase price of the acquisition over the fair value of the identifiable net tangible and intangible assets acquired recorded as goodwill. Alternatively, a gain is recorded if the fair value of assets purchased exceeds the fair value of liabilities assumed and consideration paid. The results of operations of the acquired business are included in the Condensed Consolidated Statements of Income from the effective date of the acquisition.
Loans	Loans – Loans held-for-investment are loans that the Company intends to hold until they are paid in full and are carried at the principal amount outstanding, including certain net deferred loan origination fees. Loan origination fees, commitment fees, and certain direct loan origination costs are deferred, and the net amount is amortized as a yield adjustment over the contractual life of the related loans or commitments and included in interest income. Fees related to letters of credit are amortized into fee income over the contractual life of the commitment. Other credit-related fees are recognized as fee income when earned. The Company 's net investment in direct financing leases is included in loans and consists of future minimum lease payments and estimated residual values, net of unearned income. Interest income on loans is accrued based on principal amounts outstanding. Loans held-for-sale are carried at the lower of aggregate cost or fair value and included in other assets in the Consolidated Statements of Financial Condition.
Acquired and Covered Loans	Acquired and Covered Loans – Covered loans consists of loans acquired by the Company in Federal Deposit Insurance Corporation (" FDIC ")-assisted transactions, which are covered by loss share agreements with the FDIC (the " FDIC Agreements "), under which the FDIC reimburses the Company for the majority of the losses and eligible expenses related to these assets during the coverage period. Acquired loans consist of all other loans that were acquired in business combinations that are not covered by the FDIC Agreements. Certain loans that were previously classified as covered loans are no longer covered under the FDIC Agreements, and are included in acquired loans. Covered loans and acquired loans are included within loans held-for-investment. Acquired and covered loans are separated into (i) non-purchased credit impaired (" non-PCI ") and (ii) purchased credit impaired (" PCI ") loans. Non-PCI loans include loans that did not have evidence of credit deterioration since origination at the acquisition date. PCI loans include loans that had evidence of credit deterioration since origination and for which it was probable at acquisition that the Company would not collect all contractually required principal and interest payments. Evidence of credit deterioration was evaluated using various indicators, such as past due and non-accrual status. Leases and revolving loans do not qualify to be accounted for as PCI loans and are accounted for as non-PCI loans. The acquisition adjustment related to non-PCI loans is amortized into interest income over the contractual life of the related loans. If an acquired non-PCI loan is renewed subsequent to the acquisition date, any remaining acquisition adjustment is accreted into interest income and the loan is considered a new loan that is no longer classified as an acquired loan. PCI loans are accounted for based on estimates of expected future cash flows. To estimate the fair value, the Company generally aggregates purchased consumer loans and commercial loans into pools of loans with common risk characteristics, such as delinquency status, credit score, and internal risk ratings. The fair values of larger balance commercial loans are estimated on an individual basis. Expected future cash flows in excess of the fair value of loans at the purchase date ("accretable yield") are recorded as interest income over the life of the loans if the timing and amount of the expected future cash flows can be reasonably estimated. The non-accretable yield represents the difference between contractually required payments and the expected future cash flows determined at acquisition. Subsequent increases in expected future cash flows are offset against the allowance for credit losses to the extent an allowance has been established or otherwise recognized as interest income prospectively. The present value of any decreases in expected future cash flows is recognized by recording a charge-off through the allowance for loan losses or providing an allowance for loan losses.
90-Days Past Due Loans	90-Days Past Due Loans –The Company 's accrual of interest on loans is generally discontinued at the time the loan is 90 days past due unless the credit is sufficiently collateralized and in the process of renewal or collection.
Non-accrual Loans	Non-accrual Loans – Generally, corporate loans are placed on non-accrual status (i) when either principal or interest payments become 90 days or more past due unless the credit is sufficiently collateralized and in the process of renewal or collection, or (ii) when an individual analysis of a borrower's creditworthiness warrants a downgrade to non-accrual regardless of past due status. When a loan is placed on non-accrual status, unpaid interest credited to income in the current year is reversed, and unpaid interest accrued in prior years is charged against the allowance for loan losses. After the loan is placed on non-accrual status, all debt service payments are applied to the principal on the loan. Future interest income may only be recorded on a cash basis after recovery of principal is reasonably assured. Non-accrual loans are returned to accrual status when the financial position of the borrower and other relevant factors indicate that the Company will collect all principal and interest. Commercial loans and loans secured by real estate are charged-off when deemed uncollectible. A loss is recorded if the net realizable value of the underlying collateral is less than the outstanding principal and interest. Consumer loans that are not secured by real estate are subject to mandatory charge-off at a specified delinquency date and are usually not classified as non-accrual prior to being charged-off. Closed-end consumer loans, which include installment, automobile, and single payment loans, are usually charged-off no later than the end of the month in which the loan becomes 120 days past due. PCI loans are generally considered accruing loans unless reasonable estimates of the timing and amount of expected future cash flows cannot be determined. Loans without reasonable future cash flow estimates are classified as non-accrual loans, and interest income is not recognized on those loans until the timing and amount of the expected future cash flows can be reasonably determined.
Troubled Debt Restructurings (“TDRs”)	Troubled Debt Restructurings ( " TDR s" ) – A restructuring is considered a TDR when (i) the borrower is experiencing financial difficulties, and (ii) the creditor grants a concession, such as forgiveness of principal, reduction of the interest rate, changes in payments, or extension of the maturity date. Loans are not classified as TDR s when the modification is short-term or results in an insignificant delay in payments. The Company 's TDR s are determined on a case-by-case basis. The Company does not accrue interest on a TDR unless it believes collection of all principal and interest under the modified terms is reasonably assured. For a TDR to begin accruing interest, the borrower must demonstrate some level of past performance and the future capacity to perform under the modified terms. Generally, six months of consecutive payment performance under the restructured terms is required before a TDR is returned to accrual status. However, the period could vary depending on the individual facts and circumstances of the loan. An evaluation of the borrower's current creditworthiness is used to assess the borrower's capacity to repay the loan under the modified terms. This evaluation includes an estimate of expected future cash flows, evidence of strong financial position, and estimates of the value of collateral, if applicable. For TDR s to be removed from TDR status in the calendar year after the restructuring, the loans must (i) have an interest rate and terms that reflect market conditions at the time of restructuring, and (ii) be in compliance with the modified terms. If the loan was restructured at below market rates and terms, it continues to be separately reported as restructured until it is paid in full or charged-off.
Impaired Loans	Impaired Loans – Impaired loans consist of corporate non-accrual loans and TDR s. A loan is considered impaired when it is probable that the Company will not collect all contractual principal and interest. With the exception of accruing TDR s, impaired loans are classified as non-accrual and are exclusive of smaller homogeneous loans, such as home equity, 1-4 family mortgages, and installment loans. Impaired loans with balances under a specified threshold are not individually evaluated for impairment. For all other impaired loans, impairment is measured by comparing the estimated value of the loan to the recorded book value. The value of collateral-dependent loans is based on the fair value of the underlying collateral, less costs to sell. The value of other loans is measured using the present value of expected future cash flows discounted at the loan's initial effective interest rate.
Allowance for Credit/Loan Losses and Reserve for Unfunded Commitments	Allowance for Credit Losses – The allowance for credit losses is comprised of the allowance for loan losses and the reserve for unfunded commitments, and is maintained by management at a level believed adequate to absorb estimated losses inherent in the existing loan portfolio. Determination of the allowance for credit losses is subjective since it requires significant estimates and management judgment, including the amounts and timing of expected future cash flows on impaired loans, estimated losses on pools of homogeneous loans, consideration of current economic trends, and other factors. Loans deemed to be uncollectible are charged-off against the allowance for loan losses, while recoveries of amounts previously charged-off are credited to the allowance for loan losses. Additions to the allowance for loan losses are charged to expense through the provision for loan losses. The amount of provision depends on a number of factors, including net charge-off levels, loan growth, changes in the composition of the loan portfolio, and the Company 's assessment of the allowance for loan losses based on the methodology discussed below. Allowance for Loan Losses – The allowance for loan losses consists of (i) specific reserves for individual loans where the recorded investment exceeds the value, (ii) an allowance based on a loss migration analysis that uses historical credit loss experience for each loan category, and (iii) an allowance based on other internal and external qualitative factors. The specific reserves component of the allowance for loan losses is based on a periodic analysis of impaired loans exceeding a fixed dollar amount. If the value of an impaired loan is less than the recorded book value, the Company either establishes a valuation allowance (i.e., a specific reserve) equal to the excess of the book value over the collateral value of the loan as a component of the allowance for loan losses or charges off the amount if it is a confirmed loss. The general reserve component is based on a loss migration analysis, which examines actual loss experience by loan category for a rolling 8-quarter period and the related internal risk rating for corporate loans. The loss migration analysis is updated quarterly primarily using actual loss experience. This component is then adjusted based on management's consideration of many internal and external qualitative factors, including: • Changes in the composition of the loan portfolio, trends in the volume of loans, and trends in delinquent and non-accrual loans that could indicate that historical trends do not reflect current conditions. • Changes in credit policies and procedures, such as underwriting standards and collection, charge-off, and recovery practices. • Changes in the experience, ability, and depth of credit management and other relevant staff. • Changes in the quality of the Company 's loan review system and Board of Directors oversight. • The effect of any concentration of credit and changes in the level of concentrations, such as loan type or risk rating. • Changes in the value of the underlying collateral for collateral-dependent loans. • Changes in the national and local economy that affect the collectability of various segments of the portfolio. • The effect of other external factors, such as competition and legal and regulatory requirements, on the Company 's loan portfolio. The allowance for loan losses also consists of an allowance on acquired and covered non-PCI and PCI loans. No allowance for loan losses is recorded on acquired loans at the acquisition date. Subsequent to the acquisition date, an allowance for credit losses is established as necessary to reflect credit deterioration. The acquired non-PCI allowance is based on management's evaluation of the acquired non-PCI loan portfolio giving consideration to the current portfolio balance including the remaining acquisition adjustments, maturity dates, and overall credit quality. The allowance for covered non-PCI loans is calculated in the same manner as the general reserve component based on a loss migration analysis as discussed above. The acquired and covered PCI allowance reflects the difference between the carrying value and the discounted expected future cash flows of the acquired and covered PCI loans. On a periodic basis, the adequacy of this allowance is determined through a re-estimation of expected future cash flows on all of the outstanding acquired and covered PCI loans using either a probability of default/loss given default (" PD/LGD ") methodology or a specific review methodology. The PD/LGD model is a loss model that estimates expected future cash flows using a probability of default curve and loss given default estimates. Acquired non-PCI loans that have renewed subsequent to the respective acquisition dates are no longer classified as acquired loans. Instead, they are included in the general loan population and allocated an allowance based on a loss migration analysis. Reserve for Unfunded Commitments – The Company also maintains a reserve for unfunded commitments, including letters of credit, for the risk of loss inherent in these arrangements. The reserve for unfunded commitments is estimated using the loss migration analysis from the allowance for loan losses, adjusted for probabilities of future funding requirements. The reserve for unfunded commitments is included in other liabilities in the Consolidated Statements of Financial Condition. The establishment of the allowance for credit losses involves a high degree of judgment given the difficulty of assessing the factors impacting loan repayment and estimating the timing and amount of losses. While management utilizes its best judgment and information available, the adequacy of the allowance for credit losses depends on a variety of factors beyond the Company 's control, including the performance of its loan portfolio, the economy, changes in interest rates and property values, and the interpretation of loan risk classifications by regulatory authorities.
Derivative Financial Instruments	Derivative Financial Instruments – To provide derivative products to customers and in the ordinary course of business, the Company enters into derivative transactions as part of its overall interest rate risk management strategy to minimize significant unplanned fluctuations in earnings and expected future cash flows caused by interest rate volatility. All derivative instruments are recorded at fair value as either other assets or other liabilities in the Consolidated Statements of Financial Condition. Subsequent changes in a derivative's fair value are recognized in earnings unless specific hedge accounting criteria are met. On the date the Company enters into a derivative contract, the derivative is designated as a fair value hedge, a cash flow hedge, or a non-hedge derivative instrument. Fair value hedges are designed to mitigate exposure to changes in the fair value of an asset or liability attributable to a particular risk, such as interest rate risk. Cash flow hedges are designed to mitigate exposure to variability in expected future cash flows to be received or paid related to an asset, liability, or other type of forecasted transaction. The Company formally documents all relationships between hedging instruments and hedged items, including its risk management objective and strategy at inception. At the hedge's inception and quarterly thereafter, a formal assessment is performed to determine the effectiveness of the derivative in offsetting changes in the fair values or expected future cash flows of the hedged items in the current period and prospectively. If a derivative instrument designated as a hedge is terminated or ceases to be highly effective, hedge accounting is discontinued prospectively, and the gain or loss is amortized into earnings. For fair value hedges, the gain or loss is amortized over the remaining life of the hedged asset or liability. For cash flow hedges, the gain or loss is amortized over the same period that the forecasted hedged transactions impact earnings. If the hedged item is disposed of, any fair value adjustments are included in the gain or loss from the disposition of the hedged item. If the forecasted transaction is no longer probable, the gain or loss is included in earnings immediately. For fair value hedges, changes in the fair value of the derivative instruments, as well as changes in the fair value of the hedged item, are recognized in earnings. For cash flow hedges, the effective portion of the change in fair value of the derivative instrument is reported as a component of accumulated other comprehensive loss and is reclassified to earnings when the hedged transaction is reflected in earnings. Ineffectiveness is calculated based on the change in fair value of the hedged item compared with the change in fair value of the hedging instrument. For all types of hedges, any ineffectiveness in the hedging relationship is recognized in earnings during the period the ineffectiveness occurs.
Recent Accounting Pronouncements	Adopted Accounting Pronouncements Contingent Put and Call Options in Debt Instruments: In March of 2016, the Financial Accounting Standards Board ("FASB") issued final guidance clarifying the requirements for assessing whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. Entities are required to apply the guidance to existing debt instruments (or hybrid financial instruments that are determined to have a debt host) using a modified retrospective transition method as of the period of adoption. The adoption of this guidance on January 1, 2017 did not impact the Company 's financial condition, results of operations, or liquidity. Equity Method Accounting: In March of 2016, the FASB issued final guidance to simplify the equity method of accounting. The guidance eliminates the requirement to retrospectively apply equity method accounting in previous periods when an investor initially obtains significant influence over an investee. This guidance is effective for annual and interim periods beginning after December 15, 2016. The adoption of this guidance on January 1, 2017 did not impact the Company 's financial condition, results of operations, or liquidity. Accounting for Employee Share-based Payments: In March of 2016, the FASB issued guidance to simplify the accounting for employee share-based payment transactions. The guidance requires entities to recognize the income tax effects of awards in the income statement when the awards vest or are settled. In addition, the guidance allows entities to repurchase more of an employee's shares than it can under current guidance for tax withholding purposes without triggering liability accounting and to make a policy election to account for forfeitures as they occur. The adoption of this guidance on January 1, 2017 resulted in a $638,000 tax benefit to the provision for income tax expense for the six months ended June 30, 2017 , recorded in the Company's results of operations. The Company elected to estimate forfeitures, which is consistent with the Company's practice before the adoption of this guidance. Accounting Pronouncements Pending Adoption Revenue from Contracts with Customers: In May of 2014, the FASB issued guidance that requires an entity to 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. In March of 2016, the FASB issued an amendment to this guidance to clarify the implementation of guidance on principal versus agent consideration. Additional amendments to clarify the implementation guidance on the identification of performance obligations and licensing were issued in April of 2016 and narrow-scope improvements and practical expedients were issued in May of 2016. The guidance was initially effective for annual and interim reporting periods beginning on or after December 15, 2016 but was deferred to December 15, 2017, and must be applied either retrospectively or using the modified retrospective approach. Early adoption is permitted, but not before the original effective date. The Company's revenue is comprised of net interest income on financial assets and liabilities, which are excluded from the scope of this guidance, and noninterest income. The Company expects that this guidance will change how revenue from certain revenue streams is recognized within wealth management fees but does not expect these changes to have a significant impact on the Company's financial condition, results of operations, or liquidity. The Company continues to evaluate the impact of this guidance on other components of noninterest income. The Company will adopt this guidance on January 1, 2018, using the modified retrospective approach with a cumulative effect adjustment to opening retained earnings, if an adjustment is deemed to be significant. Amendments to Guidance on Classifying and Measuring Financial Instruments: In January of 2016, the FASB issued guidance that will require entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value. Any changes in fair value will be recognized in net income unless the investments qualify for a new practicability exception. This guidance also requires entities to recognize changes in instrument-specific credit risk related to financial liabilities measured under the fair value option in other comprehensive income. No changes were made to the guidance for classifying and measuring investments in debt securities and loans. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company 's financial condition, results of operations, or liquidity. Leases: In February of 2016, the FASB issued guidance to increase transparency and comparability across entities for leasing arrangements. This guidance requires lessees to recognize assets and liabilities for most leases. For lessors, this guidance modifies the lease classification criteria and the accounting for sales-type and direct financing leases. In addition, this guidance clarifies criteria for the determination of whether a contract is or contains a lease. This guidance is effective for annual and interim periods beginning after December 15, 2018. Early adoption is permitted. During 2016, the Company entered into a sale-leaseback transaction that resulted in a deferred gain of $82.5 million , with $78.1 million remaining as of June 30, 2017 . Upon adoption of this guidance, the remaining deferred gain will be recognized immediately as a cumulative-effect adjustment to equity. For additional discussion of the sale-leaseback transaction, see Note 8 " Premises, Furniture, and Equipment ." Management is evaluating the new guidance and the additional impact to the Company 's financial condition, results of operations, or liquidity. Measurement of Credit Losses on Financial Instruments: In June of 2016, the FASB issued guidance that will require entities to present financial assets measured at amortized cost at the net amount expected to be collected, considering an entity's current estimate of all expected credit losses. In addition, credit losses relating to available-for-sale debt securities will be required to be recorded through an allowance for credit losses, with changes in credit loss estimates recognized through current earnings. This guidance is effective for annual and interim periods beginning after December 15, 2019. Early adoption is permitted, but not for periods beginning before December 15, 2018. Management is evaluating the new guidance and the impact to the Company 's financial condition, results of operations, and liquidity. Classification of Certain Cash Receipts and Cash Payments: In August of 2016, the FASB issued guidance clarifying certain cash flow presentation and classification issues to reduce diversity in practice. This guidance is effective for annual and interim reporting periods beginning on or after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company 's Consolidated Statement of Cash Flows. Income Taxes: In October of 2016, the FASB issued guidance that requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Clarifying the Definition of a Business: In January of 2017, the FASB issued guidance that clarifies the definition of a business to assist entities with evaluating whether transactions should be accounted for as acquisitions or disposals of assets or businesses. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management will apply this guidance to future transactions upon adoption. Accounting for Goodwill Impairment: In January of 2017, the FASB issued guidance that simplifies the accounting for goodwill impairment for all entities. The new guidance eliminates the requirement to calculate the implied fair value of goodwill using the second step of the quantitative two-step goodwill impairment model prescribed under current accounting guidance. Under the new guidance, if a reporting unit's carrying amount exceeds its fair value, an entity will record an impairment charge based on that difference. This guidance is effective for annual and interim goodwill impairment testing dates beginning after December 15, 2019. Early adoption is permitted for annual and interim goodwill impairment testing dates after January 1, 2017. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Presentation of Defined Benefit Retirement Plan Costs: In March of 2017, the FASB issued guidance that changes how employers that sponsor defined pension and or other postretirement benefit plans present the net periodic benefit cost in the income statement. Employers will present the service cost component of net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. Other components of net periodic benefit cost will be presented separately from the line item(s) that includes the service cost. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Premium Amortization on Purchased Callable Debt Securities: In March of 2017, the FASB issued guidance that shortens the amortization period for the premium on certain purchased callable debt securities to the earliest call date. This guidance is effective for annual and interim periods beginning after December 15, 2018. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity. Share-based Payment Award Modifications: In May of 2017, the FASB issued guidance to reduce diversity in practice by clarifying when changes to the terms or conditions of a share-based payment award must be accounted for as a modification. This guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted. Management does not expect the adoption of this guidance will materially impact the Company's financial condition, results of operations, or liquidity.

Acquisitions (Tables)

Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2017
Business Combinations [Abstract]
Schedule of Acquisition Activity	The following table presents the assets acquired and liabilities assumed, net of the fair value adjustments, in the Standard and NI Bancshares transactions as of the acquisition date. The assets acquired and liabilities assumed, both intangible and tangible, were recorded at their estimated fair values as of the acquisition date and have been accounted for under the acquisition method of accounting. Acquisition Activity (Amounts in thousands, except share and per share data) Standard NI Bancshares January 6, 2017 March 8, 2016 Assets Cash and due from banks and interest-bearing deposits in other banks $ 102,149 $ 72,533 Securities available-for-sale 214,107 125,843 Securities held-to-maturity — 1,864 FHLB and FRB stock 3,247 1,549 Loans 1,769,655 396,181 OREO 8,424 2,863 Investment in BOLI 55,629 8,384 Goodwill 339,253 22,174 Other intangible assets 31,072 10,408 Premises, furniture, and equipment 60,207 19,636 Accrued interest receivable and other assets 56,036 16,453 Total assets $ 2,639,779 $ 677,888 Liabilities Noninterest-bearing deposits $ 675,354 $ 130,909 Interest-bearing deposits 1,348,520 464,012 Total deposits 2,023,874 594,921 Borrowed funds — 2,416 Intangible liabilities — 230 Accrued interest payable and other liabilities 35,190 10,239 Total liabilities 2,059,064 607,806 Consideration Paid Common stock (2017 - 21,057,085 shares issued at $25.34 per share, 2016 - 3,042,494 shares issued at $18.059 per share), net of issuance costs 533,590 54,896 Cash paid 47,125 15,186 Total consideration paid 580,715 70,082 $ 2,639,779 $ 677,888
Unaudited Pro Forma Combined Results of Operations	The unaudited pro forma combined results of operations for the quarters and six months ended June 30, 2017 and 2016 are presented as if the Standard acquisition had occurred on January 1, 2016, the first day of the Company's 2016 fiscal year. The unaudited pro forma combined results of operations are presented for illustrative purposes only and do not necessarily indicate the financial results of the combined companies had the companies actually been combined at the beginning of the period presented. Fair value adjustments included in the following table are preliminary and may be revised. The unaudited pro forma results of operations also does not consider any potential impacts of potential revenue enhancements, anticipated cost savings and expense efficiencies, or asset dispositions, among other factors. Acquisition and integration related expenses directly attributable to the Standard acquisition have been excluded from the following table and are estimated to total $27.0 million , of which $1.2 million and $18.7 million was expensed during the quarter and six months ended June 30, 2017, respectively. Unaudited Pro Forma Combined Results of Operations (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Total revenues (1) $ 162,528 $ 154,831 $ 319,285 $ 298,176 Net income 35,652 29,304 68,386 52,465 (1) Includes net interest income and total noninterest income.
Summary of Standard Acquired Loans	The following table presents additional detail for loans acquired in the Standard transaction at the acquisition date. Standard Acquired Loans (Dollar amounts in thousands) January 6, 2017 PCI Loans Non-PCI Loans Fair value $ 125,492 $ 1,644,163 Contractually required principal and interest payments 210,891 1,938,100 Best estimate of contractual cash flows not expected to be collected (1) 57,754 100,791 Best estimate of contractual cash flows expected to be collected 153,137 1,837,309 (1) Includes interest payments not expected to be collected due to loan prepayments as well as principal and interest payments not expected to be collected due to customer default.

Securities (Tables)

Securities (Tables)	6 Months Ended
	Jun. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Securities Available-for-Sale	A summary of the Company's securities portfolio by category and maturity is presented in the following tables. Securities Portfolio (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Amortized Cost Gross Unrealized Fair Value Amortized Cost Gross Unrealized Fair Value Gains Losses Gains Losses Securities Available-for-Sale U.S. treasury securities $ 48,568 $ 19 $ (104 ) $ 48,483 $ 48,581 $ 26 $ (66 ) $ 48,541 U.S. agency securities 174,757 599 (298 ) 175,058 183,528 519 (410 ) 183,637 Collateralized mortgage obligations ("CMOs") 1,017,896 1,086 (12,818 ) 1,006,164 1,064,130 969 (17,653 ) 1,047,446 Other mortgage-backed securities ("MBSs") 377,043 1,261 (4,644 ) 373,660 337,139 1,395 (5,879 ) 332,655 Municipal securities 262,906 2,446 (950 ) 264,402 273,319 1,245 (3,718 ) 270,846 Trust-preferred collateralized debt obligations ("CDOs") 47,740 279 (14,565 ) 33,454 47,681 261 (14,682 ) 33,260 Equity securities 7,106 154 (233 ) 7,027 3,206 147 (288 ) 3,065 Total securities available-for-sale $ 1,936,016 $ 5,844 $ (33,612 ) $ 1,908,248 $ 1,957,584 $ 4,562 $ (42,696 ) $ 1,919,450 Securities Held-to-Maturity Municipal securities $ 17,353 $ — $ (2,454 ) $ 14,899 $ 22,291 $ — $ (4,079 ) $ 18,212 Trading Securities $ 19,545 $ 17,920
Securities Held-to-Maturity	A summary of the Company's securities portfolio by category and maturity is presented in the following tables. Securities Portfolio (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Amortized Cost Gross Unrealized Fair Value Amortized Cost Gross Unrealized Fair Value Gains Losses Gains Losses Securities Available-for-Sale U.S. treasury securities $ 48,568 $ 19 $ (104 ) $ 48,483 $ 48,581 $ 26 $ (66 ) $ 48,541 U.S. agency securities 174,757 599 (298 ) 175,058 183,528 519 (410 ) 183,637 Collateralized mortgage obligations ("CMOs") 1,017,896 1,086 (12,818 ) 1,006,164 1,064,130 969 (17,653 ) 1,047,446 Other mortgage-backed securities ("MBSs") 377,043 1,261 (4,644 ) 373,660 337,139 1,395 (5,879 ) 332,655 Municipal securities 262,906 2,446 (950 ) 264,402 273,319 1,245 (3,718 ) 270,846 Trust-preferred collateralized debt obligations ("CDOs") 47,740 279 (14,565 ) 33,454 47,681 261 (14,682 ) 33,260 Equity securities 7,106 154 (233 ) 7,027 3,206 147 (288 ) 3,065 Total securities available-for-sale $ 1,936,016 $ 5,844 $ (33,612 ) $ 1,908,248 $ 1,957,584 $ 4,562 $ (42,696 ) $ 1,919,450 Securities Held-to-Maturity Municipal securities $ 17,353 $ — $ (2,454 ) $ 14,899 $ 22,291 $ — $ (4,079 ) $ 18,212 Trading Securities $ 19,545 $ 17,920
Trading Securities	A summary of the Company's securities portfolio by category and maturity is presented in the following tables. Securities Portfolio (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Amortized Cost Gross Unrealized Fair Value Amortized Cost Gross Unrealized Fair Value Gains Losses Gains Losses Securities Available-for-Sale U.S. treasury securities $ 48,568 $ 19 $ (104 ) $ 48,483 $ 48,581 $ 26 $ (66 ) $ 48,541 U.S. agency securities 174,757 599 (298 ) 175,058 183,528 519 (410 ) 183,637 Collateralized mortgage obligations ("CMOs") 1,017,896 1,086 (12,818 ) 1,006,164 1,064,130 969 (17,653 ) 1,047,446 Other mortgage-backed securities ("MBSs") 377,043 1,261 (4,644 ) 373,660 337,139 1,395 (5,879 ) 332,655 Municipal securities 262,906 2,446 (950 ) 264,402 273,319 1,245 (3,718 ) 270,846 Trust-preferred collateralized debt obligations ("CDOs") 47,740 279 (14,565 ) 33,454 47,681 261 (14,682 ) 33,260 Equity securities 7,106 154 (233 ) 7,027 3,206 147 (288 ) 3,065 Total securities available-for-sale $ 1,936,016 $ 5,844 $ (33,612 ) $ 1,908,248 $ 1,957,584 $ 4,562 $ (42,696 ) $ 1,919,450 Securities Held-to-Maturity Municipal securities $ 17,353 $ — $ (2,454 ) $ 14,899 $ 22,291 $ — $ (4,079 ) $ 18,212 Trading Securities $ 19,545 $ 17,920
Remaining Contractual Maturity of Securities	Remaining Contractual Maturity of Securities (Dollar amounts in thousands) As of June 30, 2017 Available-for-Sale Held-to-Maturity Amortized Cost Fair Value Amortized Cost Fair Value One year or less $ 94,163 $ 91,946 $ 1,935 $ 1,661 After one year to five years 362,886 354,341 6,321 5,427 After five years to ten years 2,595 2,533 2,259 1,940 After ten years 74,327 72,577 6,838 5,871 Securities that do not have a single contractual maturity date 1,402,045 1,386,851 — — Total $ 1,936,016 $ 1,908,248 $ 17,353 $ 14,899
Securities Available-for-Sale Gains	The following table presents net realized gains on securities available-for-sale for the quarters and six months ended June 30, 2017 and 2016 . Securities Available-for-Sale Gains (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Gains on sales of securities: Gross realized gains $ 284 $ 149 $ 284 $ 1,079 Gross realized losses — (126 ) — (169 ) Net realized gains on sales of securities 284 23 284 910 Non-cash impairment charges: Other-than-temporary securities impairment ("OTTI") — — — — Net realized gains $ 284 $ 23 $ 284 $ 910
Securities in an Unrealized Loss Position	The following table presents the aggregate amount of unrealized losses and the aggregate related fair values of securities with unrealized losses as of June 30, 2017 and December 31, 2016 . Securities in an Unrealized Loss Position (Dollar amounts in thousands) Less Than 12 Months 12 Months or Longer Total Number of Securities Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses As of June 30, 2017 Securities Available-for-Sale U.S. treasury securities 18 $ 42,442 $ 104 $ — $ — $ 42,442 $ 104 U.S. agency securities 36 68,096 245 13,235 53 81,331 298 CMOs 186 737,140 10,196 87,787 2,622 824,927 12,818 MBSs 73 287,409 4,235 21,101 409 308,510 4,644 Municipal securities 141 58,746 868 3,623 82 62,369 950 CDOs 7 — — 30,744 14,565 30,744 14,565 Equity securities 2 — — 6,778 233 6,778 233 Total 463 $ 1,193,833 $ 15,648 $ 163,268 $ 17,964 $ 1,357,101 $ 33,612 Securities Held-to-Maturity Municipal securities 11 $ — $ — $ 14,899 $ 2,454 $ 14,899 $ 2,454 As of December 31, 2016 Securities Available-for-Sale U.S. treasury securities 16 $ 33,505 $ 61 $ 3,995 $ 5 $ 37,500 $ 66 U.S. agency securities 28 62,064 364 11,814 46 73,878 410 CMOs 194 523,233 10,309 411,758 7,344 934,991 17,653 MBSs 68 221,174 4,726 77,780 1,154 298,954 5,880 Municipal securities 380 133,957 3,059 29,280 659 163,237 3,718 CDOs 7 — — 30,592 14,682 30,592 14,682 Equity securities 2 404 201 2,319 86 2,723 287 Total 695 $ 974,337 $ 18,720 $ 567,538 $ 23,976 $ 1,541,875 $ 42,696 Securities Held-to-Maturity Municipal securities 14 $ — $ — $ 18,212 $ 4,079 $ 18,212 $ 4,079

Loans (Tables)

Loans (Tables)	6 Months Ended
	Jun. 30, 2017
Loans and Leases Receivable Disclosure [Abstract]
Composition Of Loan Portfolio	The following table presents the Company 's loans held-for-investment by class. Loan Portfolio (Dollar amounts in thousands) As of June 30, December 31, Commercial and industrial $ 3,410,748 $ 2,827,658 Agricultural 433,424 389,496 Commercial real estate: Office, retail, and industrial 1,983,802 1,581,967 Multi-family 681,032 614,052 Construction 543,892 451,540 Other commercial real estate 1,383,937 979,528 Total commercial real estate 4,592,663 3,627,087 Total corporate loans 8,436,835 6,844,241 Home equity 865,656 747,983 1-4 family mortgages 614,818 423,922 Installment 314,850 237,999 Total consumer loans 1,795,324 1,409,904 Total loans $ 10,232,159 $ 8,254,145 Deferred loan fees included in total loans $ 4,375 $ 3,838 Overdrawn demand deposits included in total loans 7,946 7,836
Schedule Of Loans Sold	The following table presents loan sales for the quarters and six months ended June 30, 2017 and 2016 . Loan Sales (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Corporate loan sales Proceeds from sales $ 19,569 $ 14,271 $ 34,937 $ 23,859 Less book value of loans sold 19,123 13,760 34,240 22,890 Net gains on corporate loan sales (1) 446 511 697 969 1-4 family mortgage loan sales Proceeds from sales $ 60,894 $ 53,258 116,655 92,765 Less book value of loans sold 59,461 52,089 114,059 90,769 Net gains on 1-4 family mortgage loan sales (2) 1,433 1,169 2,596 1,996 Total net gains on loan sales $ 1,879 $ 1,680 $ 3,293 $ 2,965 (1) Net gains on corporate loan sales are included in other service charges, commissions, and fees in the Condensed Consolidated Statements of Income. (2) Net gains on 1-4 family mortgage loan sales are included in mortgage banking income in the Condensed Consolidated Statements of Income.

Acquired and Covered Loans (Tab

Acquired and Covered Loans (Tables)	6 Months Ended
	Jun. 30, 2017
Acquired Loans [Abstract]
Acquired Loans	The following table presents the carrying amount of acquired and covered PCI and non-PCI loans as of June 30, 2017 and December 31, 2016 . Acquired and Covered Loans (1) (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 PCI Non-PCI Total PCI Non-PCI Total Acquired loans $ 161,222 $ 1,871,576 $ 2,032,798 $ 53,772 $ 613,339 $ 667,111 Covered loans 7,387 13,837 21,224 7,895 15,379 23,274 Total acquired and covered loans $ 168,609 $ 1,885,413 $ 2,054,022 $ 61,667 $ 628,718 $ 690,385 (1) Included in loans in the Consolidated Statements of Condition.
FDIC Indemnification Asset Roll Forward	Rollforwards of the carrying value of the FDIC indemnification asset for the quarters and six months ended June 30, 2017 and 2016 are presented in the following table. Changes in the FDIC Indemnification Asset (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 4,220 $ 5,680 $ 4,522 $ 3,903 Amortization (302 ) (302 ) (604 ) (582 ) Change in expected reimbursements from the FDIC for changes in expected credit losses (202 ) (475 ) (530 ) (259 ) Net payments to the FDIC 202 268 530 2,109 Ending balance $ 3,918 $ 5,171 $ 3,918 $ 5,171
Schedule Of Changes In Accretable Yield For Purchased Credit Impaired Loans	Changes in the accretable yield for acquired and covered PCI loans were as follows. Changes in Accretable Yield (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balances $ 41,249 $ 27,258 $ 19,385 $ 24,912 Additions — — 27,316 3,981 Accretion (3,888 ) (2,303 ) (7,843 ) (3,849 ) Other (1) 2,509 127 1,012 38 Ending balance $ 39,870 $ 25,082 $ 39,870 $ 25,082 (1) Increases represent a rise in the expected future cash flows to be collected over the remaining estimated life of the underlying portfolio

Past Due Loans, Allowance For29

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Tables)	6 Months Ended
	Jun. 30, 2017
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Past Due Financing Receivables	The following table presents an aging analysis of the Company 's past due loans as of June 30, 2017 and December 31, 2016 . The aging is determined without regard to accrual status. The table also presents non-performing loans, consisting of non-accrual loans (the majority of which are past due) and loans 90 days or more past due and still accruing interest, as of each balance sheet date. Aging Analysis of Past Due Loans and Non-performing Loans by Class (Dollar amounts in thousands) Aging Analysis (Accruing and Non-accrual) Non-performing Loans Current (1) 30-89 Days Past Due 90 Days or More Past Due Total Past Due Total Loans Non- accrual (2) 90 Days or More Past Due, Still Accruing Interest As of June 30, 2017 Commercial and industrial $ 3,399,763 $ 8,282 $ 2,703 $ 10,985 $ 3,410,748 $ 51,400 $ 1,550 Agricultural 432,672 379 373 752 433,424 387 — Commercial real estate: Office, retail, and industrial 1,973,608 1,847 8,347 10,194 1,983,802 15,031 — Multi-family 679,795 1,128 109 1,237 681,032 158 109 Construction 543,023 675 194 869 543,892 197 — Other commercial real estate 1,378,534 2,363 3,040 5,403 1,383,937 3,736 64 Total commercial real estate 4,574,960 6,013 11,690 17,703 4,592,663 19,122 173 Total corporate loans 8,407,395 14,674 14,766 29,440 8,436,835 70,909 1,723 Home equity 859,362 4,083 2,211 6,294 865,656 5,126 41 1-4 family mortgages 612,669 1,149 1,000 2,149 614,818 3,161 — Installment 312,132 2,423 295 2,718 314,850 — 295 Total consumer loans 1,784,163 7,655 3,506 11,161 1,795,324 8,287 336 Total loans $ 10,191,558 $ 22,329 $ 18,272 $ 40,601 $ 10,232,159 $ 79,196 $ 2,059 As of December 31, 2016 Commercial and industrial $ 2,816,442 $ 6,426 $ 4,790 $ 11,216 $ 2,827,658 $ 29,938 $ 374 Agricultural 388,596 — 900 900 389,496 181 736 Commercial real estate: Office, retail, and industrial 1,564,007 5,327 12,633 17,960 1,581,967 17,277 1,129 Multi-family 612,446 858 748 1,606 614,052 311 604 Construction 450,927 332 281 613 451,540 286 — Other commercial real estate 974,575 1,307 3,646 4,953 979,528 2,892 1,526 Total commercial real estate 3,601,955 7,824 17,308 25,132 3,627,087 20,766 3,259 Total corporate loans 6,806,993 14,250 22,998 37,248 6,844,241 50,885 4,369 Home equity 740,919 4,545 2,519 7,064 747,983 5,465 109 1-4 family mortgages 420,264 2,652 1,006 3,658 423,922 2,939 272 Installment 236,264 1,476 259 1,735 237,999 — 259 Total consumer loans 1,397,447 8,673 3,784 12,457 1,409,904 8,404 640 Total loans $ 8,204,440 $ 22,923 $ 26,782 $ 49,705 $ 8,254,145 $ 59,289 $ 5,009 (1) PCI loans with an accretable yield are considered current. (2) Includes PCI loans of $243,000 and $682,000 as of June 30, 2017 and December 31, 2016 , respectively, which no longer have an accretable yield as estimates of expected future cash flows have decreased since the acquisition due to credit deterioration.
Allowance for Credit Losses on Financing Receivables	A rollforward of the allowance for credit losses by portfolio segment for the quarters and six months ended June 30, 2017 and 2016 is presented in the table below. Allowance for Credit Losses by Portfolio Segment (Dollar amounts in thousands) Commercial, Industrial, and Agricultural Office, Retail, and Industrial Multi- family Construction Other Commercial Real Estate Consumer Reserve for Unfunded Commitments Total Allowance for Credit Losses Quarter ended June 30, 2017 Beginning balance $ 41,786 $ 17,701 $ 2,860 $ 4,110 $ 6,922 $ 14,784 $ 1,000 $ 89,163 Charge-offs (2,957 ) — — (39 ) (307 ) (1,556 ) — (4,859 ) Recoveries 400 8 6 12 79 323 — 828 Net charge-offs (2,557 ) 8 6 (27 ) (228 ) (1,233 ) — (4,031 ) Provision for loan losses and other 7,042 (2,701 ) 53 11 785 3,049 — 8,239 Ending balance $ 46,271 $ 15,008 $ 2,919 $ 4,094 $ 7,479 $ 16,600 $ 1,000 $ 93,371 Quarter ended June 30, 2016 Beginning balance $ 37,736 $ 14,420 $ 2,547 $ 2,433 $ 6,588 $ 13,426 $ 1,225 $ 78,375 Charge-offs (2,026 ) (1,641 ) (84 ) (8 ) (879 ) (1,495 ) — (6,133 ) Recoveries 576 8 1 20 69 329 — 1,003 Net charge-offs (1,450 ) (1,633 ) (83 ) 12 (810 ) (1,166 ) — (5,130 ) Provision for loan losses and other 3,798 198 469 (206 ) 1,714 2,112 175 8,260 Ending balance $ 40,084 $ 12,985 $ 2,933 $ 2,239 $ 7,492 $ 14,372 $ 1,400 $ 81,505 Six months ended June 30, 2017 Beginning balance $ 40,709 $ 17,595 $ 3,261 $ 3,444 $ 7,739 $ 13,335 $ 1,000 $ 87,083 Charge-offs (7,031 ) (127 ) — (44 ) (715 ) (3,220 ) — (11,137 ) Recoveries 2,066 983 34 239 180 766 — 4,268 Net charge-offs (4,965 ) 856 34 195 (535 ) (2,454 ) — (6,869 ) Provision for loan losses and other 10,527 (3,443 ) (376 ) 455 275 5,719 — 13,157 Ending balance $ 46,271 $ 15,008 $ 2,919 $ 4,094 $ 7,479 $ 16,600 $ 1,000 $ 93,371 Six months ended June 30, 2016 Beginning balance $ 37,074 $ 13,124 $ 2,469 $ 1,440 $ 6,109 $ 13,414 $ 1,225 $ 74,855 Charge-offs (3,924 ) (2,165 ) (288 ) (134 ) (2,324 ) (2,487 ) — (11,322 ) Recoveries 1,078 111 26 35 220 649 — 2,119 Net charge-offs (2,846 ) (2,054 ) (262 ) (99 ) (2,104 ) (1,838 ) — (9,203 ) Provision for loan losses and other 5,856 1,915 726 898 3,487 2,796 175 15,853 Ending balance $ 40,084 $ 12,985 $ 2,933 $ 2,239 $ 7,492 $ 14,372 $ 1,400 $ 81,505
Schedule of Loans and The Related Allowance For Credit Losses	The table below provides a breakdown of loans and the related allowance for credit losses by portfolio segment as of June 30, 2017 and December 31, 2016 . Loans and Related Allowance for Credit Losses by Portfolio Segment (Dollar amounts in thousands) Loans Allowance for Credit Losses Individually Evaluated for Impairment Collectively Evaluated for Impairment PCI Total Individually Evaluated for Impairment Collectively Evaluated for Impairment PCI Total As of June 30, 2017 Commercial, industrial, and agricultural $ 50,521 $ 3,763,526 $ 30,125 $ 3,844,172 $ 4,859 $ 40,922 $ 490 $ 46,271 Commercial real estate: Office, retail, and industrial 13,781 1,951,097 18,924 1,983,802 379 12,970 1,659 15,008 Multi-family 396 666,237 14,399 681,032 — 2,833 86 2,919 Construction — 528,570 15,322 543,892 — 3,945 149 4,094 Other commercial real estate 2,174 1,314,977 66,786 1,383,937 — 6,225 1,254 7,479 Total commercial real estate 16,351 4,460,881 115,431 4,592,663 379 25,973 3,148 29,500 Total corporate loans 66,872 8,224,407 145,556 8,436,835 5,238 66,895 3,638 75,771 Consumer — 1,772,271 23,053 1,795,324 — 15,173 1,427 16,600 Reserve for unfunded commitments — — — — — 1,000 — 1,000 Total loans $ 66,872 $ 9,996,678 $ 168,609 $ 10,232,159 $ 5,238 $ 83,068 $ 5,065 $ 93,371 As of December 31, 2016 Commercial, industrial, and agricultural $ 24,645 $ 3,189,327 $ 3,182 $ 3,217,154 $ 507 $ 39,554 $ 648 $ 40,709 Commercial real estate: Office, retail, and industrial 16,287 1,553,234 12,446 1,581,967 — 16,148 1,447 17,595 Multi-family 398 601,429 12,225 614,052 — 3,059 202 3,261 Construction 34 447,058 4,448 451,540 — 3,280 164 3,444 Other commercial real estate 1,286 965,900 12,342 979,528 18 6,613 1,108 7,739 Total commercial real estate 18,005 3,567,621 41,461 3,627,087 18 29,100 2,921 32,039 Total corporate loans 42,650 6,756,948 44,643 6,844,241 525 68,654 3,569 72,748 Consumer — 1,392,880 17,024 1,409,904 — 12,210 1,125 13,335 Reserve for unfunded commitments — — — — — 1,000 — 1,000 Total loans $ 42,650 $ 8,149,828 $ 61,667 $ 8,254,145 $ 525 $ 81,864 $ 4,694 $ 87,083
Impaired Financing Receivables	The following table presents the average recorded investment and interest income recognized on impaired loans by class for the quarters and six months ended June 30, 2017 and 2016 . PCI loans are excluded from this disclosure. Average Recorded Investment and Interest Income Recognized on Impaired Loans by Class (Dollar amounts in thousands) Quarters Ended June 30, 2017 2016 Average Interest Income Recognized (1) Average Interest Income Recognized (1) Commercial and industrial $ 33,648 $ 342 $ 3,236 $ 12 Agricultural 697 — — — Commercial real estate: Office, retail, and industrial 13,612 169 12,712 29 Multi-family 396 — 401 — Construction — — 34 — Other commercial real estate 2,334 8 3,641 53 Total commercial real estate 16,342 177 16,788 82 Total impaired loans $ 50,687 $ 519 $ 20,024 $ 94 Six Months Ended June 30, 2017 2016 Average Interest (1) Average Interest (1) Commercial and industrial $ 30,647 $ 556 $ 3,114 $ 50 Agricultural 464 — — — Commercial real estate: Office, retail, and industrial 14,503 262 10,529 77 Multi-family 397 28 534 1 Construction 11 136 82 — Other commercial real estate 1,984 20 3,649 72 Total commercial real estate 16,895 446 14,794 150 Total impaired loans $ 48,006 $ 1,002 $ 17,908 $ 200 (1) Recorded using the cash basis of accounting. The following table presents loans individually evaluated for impairment by class of loan as of June 30, 2017 and December 31, 2016 . PCI loans are excluded from this disclosure. Impaired Loans Individually Evaluated by Class (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Recorded Investment In Recorded Investment In Loans with No Specific Reserve Loans with a Specific Reserve Unpaid Principal Balance Specific Reserve Loans with No Specific Reserve Loans with a Specific Reserve Unpaid Principal Balance Specific Reserve Commercial and industrial $ 16,215 $ 34,027 $ 53,545 $ 4,859 $ 11,579 $ 13,066 $ 29,514 $ 507 Agricultural 279 — 1,629 — — — — — Commercial real estate: Office, retail, and industrial 10,125 3,656 16,966 379 16,287 — 21,057 — Multi-family 396 — 396 — 398 — 398 — Construction — — — — 34 — 34 — Other commercial real estate 2,174 — 2,271 — 1,016 270 2,141 18 Total commercial real estate 12,695 3,656 19,633 379 17,735 270 23,630 18 Total impaired loans individually evaluated for impairment $ 29,189 $ 37,683 $ 74,807 $ 5,238 $ 29,314 $ 13,336 $ 53,144 $ 525
Financing Receivable Credit Quality Indicators	Consumer Credit Quality Indicators by Class (Dollar amounts in thousands) Performing Non-accrual Total As of June 30, 2017 Home equity $ 860,530 $ 5,126 $ 865,656 1-4 family mortgages 611,657 3,161 614,818 Installment 314,850 — 314,850 Total consumer loans $ 1,787,037 $ 8,287 $ 1,795,324 As of December 31, 2016 Home equity $ 727,618 $ 4,986 $ 732,604 1-4 family mortgages 413,415 2,939 416,354 Installment 237,999 — 237,999 Total consumer loans $ 1,379,032 $ 7,925 $ 1,386,957 The following tables present credit quality indicators by class for corporate and consumer loans, as of June 30, 2017 and December 31, 2016 . Corporate Credit Quality Indicators by Class (Dollar amounts in thousands) Pass Special Mention (1) (4) Substandard (2) (4) Non-accrual (3) Total As of June 30, 2017 Commercial and industrial $ 3,199,001 $ 67,252 $ 93,095 $ 51,400 $ 3,410,748 Agricultural 409,969 14,464 8,604 387 433,424 Commercial real estate: Office, retail, and industrial 1,896,327 27,894 44,550 15,031 1,983,802 Multi-family 673,946 5,051 1,877 158 681,032 Construction 523,046 8,739 11,910 197 543,892 Other commercial real estate 1,338,382 21,137 20,682 3,736 1,383,937 Total commercial real estate 4,431,701 62,821 79,019 19,122 4,592,663 Total corporate loans $ 8,040,671 $ 144,537 $ 180,718 $ 70,909 $ 8,436,835 As of December 31, 2016 Commercial and industrial $ 2,638,833 $ 92,340 $ 66,547 $ 29,938 $ 2,827,658 Agricultural 366,382 17,039 5,894 181 389,496 Commercial real estate: Office, retail, and industrial 1,491,030 34,007 39,513 17,277 1,581,827 Multi-family 607,324 4,370 2,029 311 614,034 Construction 438,946 111 12,197 286 451,540 Other commercial real estate 951,115 11,808 13,544 2,892 979,359 Total commercial real estate 3,488,415 50,296 67,283 20,766 3,626,760 Total corporate loans $ 6,493,630 $ 159,675 $ 139,724 $ 50,885 $ 6,843,914 (1) Loans categorized as special mention exhibit potential weaknesses that require the close attention of management since these potential weaknesses may result in the deterioration of repayment prospects in the future. (2) Loans categorized as substandard exhibit well-defined weaknesses that may jeopardize the liquidation of the debt. These loans continue to accrue interest because they are well-secured and collection of principal and interest is expected within a reasonable time. (3) Loans categorized as non-accrual exhibit well-defined weaknesses that may jeopardize the liquidation of the debt or result in a loss if the deficiencies are not corrected. (4) Total special mention and substandard loans includes accruing TDR s of $669,000 as of June 30, 2017 and $834,000 as of December 31, 2016 .
Troubled Debt Restructuring Activity Rollforward	The table below presents TDR s by class as of June 30, 2017 and December 31, 2016 . See Note 1, "Summary of Significant Accounting Policies," for the accounting policy for TDR s. TDR s by Class (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Accruing Non-accrual (1) Total Accruing Non-accrual (1) Total Commercial and industrial $ 273 $ 891 $ 1,164 $ 281 $ 150 $ 431 Agricultural — — — — — — Commercial real estate: Office, retail, and industrial — 860 860 155 4,733 4,888 Multi-family 579 158 737 586 168 754 Construction — — — — — — Other commercial real estate 197 — 197 268 48 316 Total commercial real estate 776 1,018 1,794 1,009 4,949 5,958 Total corporate loans 1,049 1,909 2,958 1,290 5,099 6,389 Home equity 168 771 939 177 820 997 1-4 family mortgages 812 356 1,168 824 378 1,202 Installment — — — — — — Total consumer loans 980 1,127 2,107 1,001 1,198 2,199 Total loans $ 2,029 $ 3,036 $ 5,065 $ 2,291 $ 6,297 $ 8,588 (1) These TDR s are included in non-accrual loans in the preceding tables. A rollforward of the carrying value of TDR s for the quarters and six months ended June 30, 2017 and 2016 is presented in the following table. TDR Rollforward (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Accruing Beginning balance $ 2,112 $ 2,702 $ 2,291 $ 2,743 Additions — — 922 — Net payments received (83 ) (28 ) (107 ) (69 ) Net transfers to non-accrual — (183 ) (1,077 ) (183 ) Ending balance 2,029 2,491 2,029 2,491 Non-accrual Beginning balance 3,112 2,268 6,297 2,324 Net payments received (75 ) (522 ) (4,225 ) (578 ) Charge-offs (1 ) (239 ) (113 ) (239 ) Net transfers from accruing — 183 1,077 183 Ending balance 3,036 1,690 3,036 1,690 Total TDRs $ 5,065 $ 4,181 $ 5,065 $ 4,181

Premises, Furniture, and Equi30

Premises, Furniture, and Equipment (Tables)	6 Months Ended
	Jun. 30, 2017
Property, Plant and Equipment [Abstract]
Summary of Premises, Furniture, and Equipment	The following table summarizes the Company's premises, furniture, and equipment by category. Premises, Furniture, and Equipment (Dollar amounts in thousands) As of June 30, December 31, Land $ 31,623 $ 18,304 Premises 139,137 94,369 Furniture and equipment 135,328 105,859 Total cost 306,088 218,532 Accumulated depreciation (182,075 ) (140,030 ) Net book value of premises, furniture, and equipment 124,013 78,502 Assets held-for-sale 11,732 4,075 Total premises, furniture, and equipment $ 135,745 $ 82,577
Schedule of Future Minimum Lease Payments for Operating Leases	The following summary reflects the future minimum payments by year required under operating leases that have initial or remaining non-cancelable lease terms in excess of one year as of June 30, 2017 . Future Minimum Operating Lease Payments (Dollar amounts in thousands) Total One year or less $ 18,383 After one year to two years 16,751 After two years to three years 16,606 After three years to four years 16,268 After four years to five years 16,119 After five years 120,356 Total minimum lease payments $ 204,483
Scheduled Accretion of Operating Lease Intangible	The following table presents the remaining scheduled accretion of the intangible liability by year. Scheduled Accretion of Operating Lease Intangible (Dollar amounts in thousands) Total One year or less $ 1,095 After one year to two years 791 After two years to three years 648 After three years to four years 648 After four years to five years 648 After five years 3,673 Total accretion $ 7,503
Schedule Of Net Operating Lease Expense	The following table presents net operating lease expense for the quarters and six months ended June 30, 2017 and 2016 . Net Operating Lease Expense (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Lease expense charged to operations $ 4,721 $ 1,773 $ 9,280 $ 3,500 Accretion of operating lease intangible (1) (295 ) (295 ) (590 ) (581 ) Accretion of deferred gain on sale-leaseback transaction (1) (1,473 ) — (2,946 ) — Rental income from premises leased to others (1) (169 ) (128 ) (350 ) (286 ) Net operating lease expense $ 2,784 $ 1,350 $ 5,394 $ 2,633 (1) Included as reductions to net occupancy and equipment expense in the Condensed Consolidated Statements of Income.

Goodwill and Other Intangible31

Goodwill and Other Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table presents changes in the carrying amount of goodwill for the quarters and six months ended June 30, 2017 and 2016 . Changes in the Carrying Amount of Goodwill (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 691,572 $ 339,768 $ 340,879 $ 319,007 Acquisitions (45 ) 1,745 350,648 22,506 Ending balance $ 691,527 $ 341,513 $ 691,527 $ 341,513
Schedule of Finite-Lived Intangible Assets	Other Intangible Assets (Dollar amounts in thousands) Six Months Ended June 30, 2017 2016 Gross Accumulated Amortization Net Gross Accumulated Amortization Net Beginning balance $ 58,959 $ 32,962 $ 25,997 $ 48,550 $ 28,280 $ 20,270 Additions 39,017 — 39,017 10,409 — 10,409 Amortization expense — 4,128 (4,128 ) — 2,230 (2,230 ) Ending balance $ 97,976 $ 37,090 $ 60,886 $ 58,959 $ 30,510 $ 28,449
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Scheduled Amortization of Other Intangible Assets (Dollar amounts in thousands) Total Year Ending June 30, 2018 $ 7,332 2019 7,086 2020 7,055 2021 6,986 2022 6,908 2023 and thereafter 25,519 Total $ 60,886

Deposits (Tables)

Deposits (Tables)	6 Months Ended
	Jun. 30, 2017
Deposits [Abstract]
Schedule Of Deposits	The following table presents the Company's deposits by type. Summary of Deposits (Dollar amounts in thousands) As of June 30, December 31, Demand deposits $ 3,525,905 $ 2,766,748 Savings deposits 2,059,833 1,615,833 NOW accounts 1,970,036 1,675,421 Money market deposits 1,905,402 1,577,316 Time deposits less than $100,000 894,530 755,558 Time deposits greater than $100,000 644,014 437,727 Total deposits $ 10,999,720 $ 8,828,603

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The table below displays the calculation of basic and diluted earnings per common share (" EPS "). Basic and Diluted EPS (Amounts in thousands, except per share data) Quarters Ended Six Months Ended 2017 2016 2017 2016 Net income $ 34,950 $ 25,267 $ 57,805 $ 43,229 Net income applicable to non-vested restricted shares (336 ) (290 ) (570 ) (502 ) Net income applicable to common shares $ 34,614 $ 24,977 $ 57,235 $ 42,727 Weighted-average common shares outstanding: Weighted-average common shares outstanding (basic) 101,743 80,383 101,081 79,182 Dilutive effect of common stock equivalents 20 13 20 12 Weighted-average diluted common shares outstanding 101,763 80,396 101,101 79,194 Basic EPS $ 0.34 $ 0.31 $ 0.57 $ 0.54 Diluted EPS $ 0.34 $ 0.31 $ 0.57 $ 0.54 Anti-dilutive shares not included in the computation of diluted EPS (1) 195 469 269 539 (1) This amount represents outstanding stock options for which the exercise price is greater than the average market price of the Company's common stock.

Derivative Instruments and He34

Derivative Instruments and Hedging Activities (Tables)	6 Months Ended
	Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Interest Rate Derivatives	Fair Value Hedges (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Gross notional amount outstanding $ 5,708 $ 5,958 Derivative liability fair value (186 ) (282 ) Weighted-average interest rate received 3.08 % 2.63 % Weighted-average interest rate paid 5.96 % 5.96 % Weighted-average maturity (in years) 1.35 1.84 Fair value of derivative (1) $ 197 $ 296 (1) This amount represents the fair value if credit risk related contingent features were triggered. Cash Flow Hedges (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Gross notional amount outstanding $ 1,960,000 $ 1,470,000 Derivative asset fair value 3,528 5,402 Derivative liability fair value (7,627 ) (7,390 ) Weighted-average interest rate received 1.51 % 1.37 % Weighted-average interest rate paid 1.40 % 1.11 % Weighted-average maturity (in years) 2.75 2.83
Schedule of Derivative Instruments	Other Derivative Instruments (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Gross notional amount outstanding $ 2,252,704 $ 1,656,612 Derivative asset fair value 17,370 13,478 Derivative liability fair value (15,347 ) (13,478 ) Fair value of derivative (1) 15,605 13,753 (1) This amount represents the fair value if credit risk related contingent features were triggered.
Offsetting Assets	The following table presents the fair value of the Company's derivatives and offsetting positions as of June 30, 2017 and December 31, 2016 . Fair Value of Offsetting Derivatives (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Assets Liabilities Assets Liabilities Gross amounts recognized $ 20,898 $ 23,160 $ 18,880 $ 21,150 Less: amounts offset in the Consolidated Statements of Financial Condition — — — — Net amount presented in the Consolidated Statements of Financial Condition (1) 20,898 23,160 18,880 21,150 Gross amounts not offset in the Consolidated Statements of Financial Condition: Offsetting derivative positions (8,646 ) (8,646 ) (10,889 ) (10,889 ) Cash collateral pledged — (14,514 ) — (10,261 ) Net credit exposure $ 12,252 $ — $ 7,991 $ — (1) Included in other assets or other liabilities in the Consolidated Statements of Financial Condition.
Offsetting Liabilities	The following table presents the fair value of the Company's derivatives and offsetting positions as of June 30, 2017 and December 31, 2016 . Fair Value of Offsetting Derivatives (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Assets Liabilities Assets Liabilities Gross amounts recognized $ 20,898 $ 23,160 $ 18,880 $ 21,150 Less: amounts offset in the Consolidated Statements of Financial Condition — — — — Net amount presented in the Consolidated Statements of Financial Condition (1) 20,898 23,160 18,880 21,150 Gross amounts not offset in the Consolidated Statements of Financial Condition: Offsetting derivative positions (8,646 ) (8,646 ) (10,889 ) (10,889 ) Cash collateral pledged — (14,514 ) — (10,261 ) Net credit exposure $ 12,252 $ — $ 7,991 $ — (1) Included in other assets or other liabilities in the Consolidated Statements of Financial Condition.

Commitments, Guarantees, and 35

Commitments, Guarantees, and Contingent Liabilities (Tables)	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments Disclosure	Contractual or Notional Amounts of Financial Instruments (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Commitments to extend credit: Commercial, industrial, and agricultural $ 1,750,477 $ 1,522,152 Commercial real estate 347,330 397,423 Home equity 508,295 426,384 Other commitments (1) 248,320 214,943 Total commitments to extend credit $ 2,854,422 $ 2,560,902 Letters of credit $ 137,913 $ 100,430 Recourse on assets sold: Unpaid principal balance of loans sold $ 185,182 $ 187,158 Carrying value of recourse obligation (2) 153 142 (1) Other commitments includes installment and overdraft protection program commitments. (2) Included in other liabilities in the Consolidated Statements of Financial Condition.

Fair Value (Tables)

Fair Value (Tables)	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring Basis	The following table provides the fair value for assets and liabilities required to be measured at fair value on a recurring basis in the Consolidated Statements of Financial Condition by level in the fair value hierarchy. Recurring Fair Value Measurements (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets: Trading securities: Money market funds $ 1,717 $ — $ — $ 1,645 $ — $ — Mutual funds 17,828 — — 16,275 — — Total trading securities 19,545 — — 17,920 — — Securities available-for-sale: U.S. treasury securities 48,483 — — 48,541 — — U.S. agency securities — 175,058 — — 183,637 — CMOs — 1,006,164 — — 1,047,446 — MBSs — 373,660 — — 332,655 — Municipal securities — 264,402 — — 270,846 — CDOs — — 33,454 — — 33,260 Equity securities — 7,027 — — 3,065 — Total securities available-for-sale 48,483 1,826,311 33,454 48,541 1,837,649 33,260 Mortgage servicing rights ("MSRs") (1) — — 5,925 6,120 Derivative assets (1) — 20,898 — — 18,880 — Liabilities: Derivative liabilities (2) $ — $ 23,160 $ — $ — $ 21,150 $ — (1) Included in other assets in the Consolidated Statements of Financial Condition. (2) Included in other liabilities in the Consolidated Statements of Financial Condition.
Significant Unobservable Inputs Used in the Valuation of CDOs	The following table presents the ranges of significant, unobservable inputs used by the Company to determine the fair value of MSR s as of June 30, 2017 and December 31, 2016 . Significant Unobservable Inputs Used in the Valuation of MSR s As of June 30, 2017 December 31, 2016 Prepayment speed 8.8 % - 25.3% 7.7 % - 22.8% Maturity (months) 8 - 92 12 - 103 Discount rate 9.5 % - 13.0% 9.5 % - 13.0% The following table presents the ranges of significant, unobservable inputs calculated using the weighted-average of the Issuers used by the Company as of June 30, 2017 and December 31, 2016. Significant Unobservable Inputs Used in the Valuation of CDOs As of June 30, 2017 December 31, 2016 Probability of prepayment 0.0 % - 10.9% 0.0 % - 10.9% Probability of default 15.6 % - 44.1% 16.7 % - 46.8% Loss given default 93.3 % - 99.2% 93.3 % - 98.9% Probability of deferral cure 0.0 % - 100.0% 7.6 % - 100.0%
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	A rollforward of the carrying value of CDOs for the quarters and six months ended June 30, 2017 and 2016 is presented in the following table. Carrying Value of CDOs (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 33,436 $ 30,757 $ 33,260 $ 31,529 Change in other comprehensive income (1) 6 (244 ) 135 (1,030 ) Other 12 (82 ) 59 (68 ) Ending balance $ 33,454 $ 30,431 $ 33,454 $ 30,431 (1) Included in unrealized holding gains in the Consolidated Statements of Comprehensive Income.
Significant Unobservable Inputs Used in the Valuation of MSRs	The following table presents the ranges of significant, unobservable inputs used by the Company to determine the fair value of MSR s as of June 30, 2017 and December 31, 2016 . Significant Unobservable Inputs Used in the Valuation of MSR s As of June 30, 2017 December 31, 2016 Prepayment speed 8.8 % - 25.3% 7.7 % - 22.8% Maturity (months) 8 - 92 12 - 103 Discount rate 9.5 % - 13.0% 9.5 % - 13.0% The following table presents the ranges of significant, unobservable inputs calculated using the weighted-average of the Issuers used by the Company as of June 30, 2017 and December 31, 2016. Significant Unobservable Inputs Used in the Valuation of CDOs As of June 30, 2017 December 31, 2016 Probability of prepayment 0.0 % - 10.9% 0.0 % - 10.9% Probability of default 15.6 % - 44.1% 16.7 % - 46.8% Loss given default 93.3 % - 99.2% 93.3 % - 98.9% Probability of deferral cure 0.0 % - 100.0% 7.6 % - 100.0%
Schedule of Servicing Assets at Fair Value	A rollforward of the carrying value of MSR s for the quarters and six months ended June 30, 2017 and 2016 is presented in the following table. Carrying Value of MSR s (Dollar amounts in thousands) Quarters Ended Six Months Ended 2017 2016 2017 2016 Beginning balance $ 6,245 $ 5,022 $ 6,120 $ 1,853 Additions from acquisition — — — 3,092 New MSRs 205 162 361 347 Total gains (losses) included in earnings (1) : Changes in valuation inputs and assumptions (260 ) (132 ) (88 ) (172 ) Other changes in fair value (2) (265 ) (114 ) (468 ) (182 ) Ending balance $ 5,925 $ 4,938 $ 5,925 $ 4,938 Contractual servicing fees earned (1) $ 384 $ 366 $ 779 $ 549 (1) Included in mortgage banking income in the Condensed Consolidated Statements of Income and related to assets held as of June 30, 2017 and 2016 . (2) Primarily represents changes in expected future cash flows due to payoffs and paydowns.
Fair Value Measurements, Nonrecurring	The following table provides the fair value for each class of assets and liabilities required to be measured at fair value on a non-recurring basis in the Consolidated Statements of Financial Condition by level in the fair value hierarchy. Non-Recurring Fair Value Measurements (Dollar amounts in thousands) As of June 30, 2017 As of December 31, 2016 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Collateral-dependent impaired loans (1) $ — $ — $ 40,698 $ — $ — $ 22,019 OREO (2) — — 6,835 — — 8,624 Loans held-for-sale (3) — — 16,922 — — 10,484 Assets held-for-sale (4) — — 11,732 — — 4,075 (1) Includes impaired loans with charge-offs and impaired loans with a specific reserve during the periods presented. (2) Includes OREO with fair value adjustments subsequent to initial transfer that occurred during the periods presented. (3) Included in other assets in the Consolidated Statements of Financial Condition. (4) Included in premises, furniture, and equipment in the Consolidated Statements of Financial Condition.
Fair Value, by Balance Sheet Grouping	For certain financial instruments that are not required to be measured at fair value in the Consolidated Statements of Financial Condition, the Company must disclose the estimated fair values and the level within the fair value hierarchy as shown in the following table. Fair Value Measurements of Other Financial Instruments (Dollar amounts in thousands) As of June 30, 2017 December 31, 2016 Fair Value Hierarchy Level Carrying Amount Fair Value Carrying Amount Fair Value Assets: Cash and due from banks 1 $ 181,171 $ 181,171 $ 155,055 $ 155,055 Interest-bearing deposits in other banks 2 103,181 103,181 107,093 107,093 Securities held-to-maturity 2 17,353 14,899 22,291 18,212 FHLB and FRB stock 2 66,333 66,333 59,131 59,131 Loans 3 10,143,706 9,905,748 8,172,584 7,973,845 Investment in BOLI 3 278,353 278,353 219,746 219,746 Accrued interest receivable 3 39,766 39,766 34,384 34,384 Other interest-earning assets 3 454 454 834 834 Liabilities: Deposits 2 $ 10,999,720 $ 10,989,384 $ 8,828,603 $ 8,820,572 Borrowed funds 2 639,333 639,333 879,008 879,008 Senior and subordinated debt 2 194,886 205,757 194,603 197,888 Accrued interest payable 2 4,470 4,470 3,416 3,416

Recent Accounting Pronounceme37

Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Share-based compensation tax benefit	$ 638
Deferred gain, net	$ 78,100	$ 82,500

Acquisitions (Details) - Narrat

Acquisitions (Details) - Narrative $ / shares in Units, $ in Thousands

Jan. 06, 2017USD ($)$ / sharesshares

Mar. 08, 2016USD ($)locationshares

Jun. 30, 2017USD ($)

Jun. 30, 2016USD ($)

Jun. 30, 2017USD ($)

Jun. 30, 2016USD ($)

Dec. 31, 2017USD ($)

Mar. 31, 2017USD ($)

Feb. 28, 2017USD ($)

Dec. 31, 2016USD ($)

Mar. 31, 2016USD ($)

Dec. 31, 2015USD ($)

Business Acquisition [Line Items]

Goodwill

$ 691,527

$ 341,513

$ 691,527

$ 341,513

$ 691,572

$ 340,879

$ 339,768

$ 319,007

Acquisition and integration related expenses

1,174

$ 618

19,739

$ 5,638

Standard Bancshares, Inc.

Business Acquisition [Line Items]

Fixed exchange ratio (in Shares) | shares

0.4350

Consideration transferred

$ 580,715

Common stock, shares issued (in Shares) | shares

21,057,085

Cash paid

$ 47,125

Goodwill

$ 339,253

Acquisition and integration related expenses

$ 1,200

$ 18,700

Premier Asset Management LLC

Business Acquisition [Line Items]

Assets under management acquired

$ 550,000

NI Bancshares Corporation

Business Acquisition [Line Items]

Consideration transferred

$ 70,082

Common stock, shares issued (in Shares) | shares

3,042,494

Cash paid

$ 15,186

Goodwill

$ 22,174

Number of retail branches acquired | location

10

Minimum value of trust assets under management acquired

$ 700,000

Standard Bancshares, Inc.

Business Acquisition [Line Items]

Share price (in Dollars per share) | $ / shares

$ 11.02

First Midwest Bancorp, Inc

Business Acquisition [Line Items]

Share price (in Dollars per share) | $ / shares

$ 25.34

Scenario, Forecast | Standard Bancshares, Inc.

Business Acquisition [Line Items]

Estimated acquisition and integration related expenses

$ 27,000

Acquisitions (Details) - Acquis

Acquisitions (Details) - Acquisition Activity - USD ($) $ / shares in Units, $ in Thousands	Jan. 06, 2017	Mar. 08, 2016	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Assets
Goodwill			$ 691,527	$ 691,572	$ 340,879	$ 341,513	$ 339,768	$ 319,007
Liabilities
Intangible liabilities			$ 7,503
Standard Bancshares, Inc.
Assets
Cash and due from banks and interest-bearing deposits in other banks	$ 102,149
Securities available-for-sale	214,107
Securities held-to-maturity	0
FHLB and FRB stock	3,247
Loans	1,769,655
OREO	8,424
Investment in BOLI	55,629
Goodwill	339,253
Other intangible assets	31,072
Premises, furniture, and equipment	60,207
Accrued interest receivable and other assets	56,036
Total assets	2,639,779
Liabilities
Noninterest-bearing deposits	675,354
Interest-bearing deposits	1,348,520
Total deposits	2,023,874
Borrowed funds	0
Intangible liabilities	0
Accrued interest payable and other liabilities	35,190
Total liabilities	2,059,064
Consideration Paid
Common stock (2017 - 21,057,085 shares issued at $25.34 per share, 2016 - 3,042,494 shares issued at $18.059 per share), net of issuance costs	533,590
Cash paid	47,125
Total consideration paid	$ 580,715
Common stock, shares issued (in Shares)	21,057,085
Shares issued (in dollars per share)	$ 25.34
NI Bancshares Corporation
Assets
Cash and due from banks and interest-bearing deposits in other banks		$ 72,533
Securities available-for-sale		125,843
Securities held-to-maturity		1,864
FHLB and FRB stock		1,549
Loans		396,181
OREO		2,863
Investment in BOLI		8,384
Goodwill		22,174
Other intangible assets		10,408
Premises, furniture, and equipment		19,636
Accrued interest receivable and other assets		16,453
Total assets		677,888
Liabilities
Noninterest-bearing deposits		130,909
Interest-bearing deposits		464,012
Total deposits		594,921
Borrowed funds		2,416
Intangible liabilities		230
Accrued interest payable and other liabilities		10,239
Total liabilities		607,806
Consideration Paid
Common stock (2017 - 21,057,085 shares issued at $25.34 per share, 2016 - 3,042,494 shares issued at $18.059 per share), net of issuance costs		54,896
Cash paid		15,186
Total consideration paid		$ 70,082
Common stock, shares issued (in Shares)		3,042,494
Shares issued (in dollars per share)		$ 18.059

Acquisitions (Details) - Unaudi

Acquisitions (Details) - Unaudited Pro Forma Combined Results of Operations (Details) - Standard Bancshares, Inc. - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Business Acquisition [Line Items]
Total revenues	[1]	$ 162,528	$ 154,831	$ 319,285	$ 298,176
Net income		$ 35,652	$ 29,304	$ 68,386	$ 52,465
[1]	Includes net interest income and total noninterest income.

Acquisitions (Details) - Acquir

Acquisitions (Details) - Acquired Loans - Standard Bancshares, Inc. - Acquired loans $ in Thousands	Jan. 06, 2017USD ($)
Business Acquisition [Line Items]
Fair value of acquired loans	$ 1,644,163
Contractually required principal and interest payments	1,938,100
Best estimate of contractual cash flows not expected to be collected	100,791	[1]
Best estimate of contractual cash flows expected to be collected	1,837,309
Receivables acquired with deteriorated credit quality
Business Acquisition [Line Items]
Fair value of acquired loans	125,492
Contractually required principal and interest payments	210,891
Best estimate of contractual cash flows not expected to be collected	57,754	[1]
Best estimate of contractual cash flows expected to be collected	$ 153,137
[1]	Includes interest payments not expected to be collected due to loan prepayments as well as principal and interest payments not expected to be collected due to customer default.

Securities (Details) - Securiti

Securities (Details) - Securities Portfolio - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	$ 19,545	$ 17,920
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,936,016	1,957,584
Gross Unrealized Gains	5,844	4,562
Gross Unrealized Losses	(33,612)	(42,696)
Fair Value	1,908,248	1,919,450
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	17,353	22,291
Fair Value	14,899
U.S. treasury securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	48,568	48,581
Gross Unrealized Gains	19	26
Gross Unrealized Losses	(104)	(66)
Fair Value	48,483	48,541
U.S. agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	174,757	183,528
Gross Unrealized Gains	599	519
Gross Unrealized Losses	(298)	(410)
Fair Value	175,058	183,637
Collateralized mortgage obligations (CMOs)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,017,896	1,064,130
Gross Unrealized Gains	1,086	969
Gross Unrealized Losses	(12,818)	(17,653)
Fair Value	1,006,164	1,047,446
Other mortgage-backed securities (MBSs)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	377,043	337,139
Gross Unrealized Gains	1,261	1,395
Gross Unrealized Losses	(4,644)	(5,879)
Fair Value	373,660	332,655
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	262,906	273,319
Gross Unrealized Gains	2,446	1,245
Gross Unrealized Losses	(950)	(3,718)
Fair Value	264,402	270,846
Trust-preferred collateralized debt obligations (CDOs)
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	47,740	47,681
Gross Unrealized Gains	279	261
Gross Unrealized Losses	(14,565)	(14,682)
Fair Value	33,454	33,260
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,106	3,206
Gross Unrealized Gains	154	147
Gross Unrealized Losses	(233)	(288)
Fair Value	7,027	3,065
Trading Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	19,545	17,920
Municipal securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	17,353	22,291
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2,454)	(4,079)
Fair Value	$ 14,899	$ 18,212

Securities (Details) - Remainin

Securities (Details) - Remaining Contractual Maturity of Securities - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Available-for-sale Securities, Amortized Cost [Abstract]
One year or less	$ 94,163
After one year to five years	362,886
After five years to ten years	2,595
After ten years	74,327
Securities that do not have a single contractual maturity date	1,402,045
Amortized Cost	1,936,016	$ 1,957,584
Available-for-sale Securities, Fair Value [Abstract]
One year or less	91,946
After one year to five years	354,341
After five years to ten years	2,533
After ten years	72,577
Securities that do not have a single contractual maturity date	1,386,851
Fair Value	1,908,248	1,919,450
Held-to-maturity Securities, Amortized Cost [Abstract]
One year or less	1,935
After one year to five years	6,321
After five years to ten years	2,259
After ten years	6,838
Securities that do not have a single contractual maturity date	0
Amortized Cost	17,353	$ 22,291
Held-to-maturity Securities, Fair Value [Abstract]
One year or less	1,661
After one year to five years	5,427
After five years to ten years	1,940
After ten years	5,871
Securities that do not have a single contractual maturity date	0
Fair Value	$ 14,899

Securities (Details) - Narrativ

Securities (Details) - Narrative - USD ($)	3 Months Ended
	Mar. 31, 2017	Jun. 30, 2017	Jan. 06, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Available-for-sale securities pledged as collateral		$ 1,100,000,000		$ 1,100,000,000
Held-to-maturity securities pledged as collateral		0		0
Business Acquisition [Line Items]
Carrying value of securities sold	$ 210,200,000
OTTI balance		$ 23,300,000		$ 23,300,000
Standard Bancshares, Inc.
Business Acquisition [Line Items]
Securities available-for-sale			$ 214,107,000

Securities (Details) - Securi45

Securities (Details) - Securities Gains (Losses) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Gains on sales of securities:
Gross realized gains	$ 284	$ 149	$ 284	$ 1,079
Gross realized losses	0	(126)	0	(169)
Net realized gains on sales of securities	284	23	284	910
Non-cash impairment charges:
Other-than-temporary securities impairment (OTTI)	0	0	0	0
Net realized gains	$ 284	$ 23	$ 284	$ 910

Securities (Details) - Securi46

Securities (Details) - Securities In An Unrealized Loss Position $ in Thousands	Jun. 30, 2017USD ($)security	Dec. 31, 2016USD ($)security
Securities Available-for-Sale
Number of Securities | security	463	695
Fair Value
Less Than 12 Months	$ 1,193,833	$ 974,337
12 Months or Longer	163,268	567,538
Total	1,357,101	1,541,875
Unrealized Losses
Less Than 12 Months	15,648	18,720
12 Months or Longer	17,964	23,976
Total	$ 33,612	$ 42,696
U.S. treasury securities
Securities Available-for-Sale
Number of Securities | security	18	16
Fair Value
Less Than 12 Months	$ 42,442	$ 33,505
12 Months or Longer	0	3,995
Total	42,442	37,500
Unrealized Losses
Less Than 12 Months	104	61
12 Months or Longer	0	5
Total	$ 104	$ 66
U.S. agency securities
Securities Available-for-Sale
Number of Securities | security	36	28
Fair Value
Less Than 12 Months	$ 68,096	$ 62,064
12 Months or Longer	13,235	11,814
Total	81,331	73,878
Unrealized Losses
Less Than 12 Months	245	364
12 Months or Longer	53	46
Total	$ 298	$ 410
CMOs
Securities Available-for-Sale
Number of Securities | security	186	194
Fair Value
Less Than 12 Months	$ 737,140	$ 523,233
12 Months or Longer	87,787	411,758
Total	824,927	934,991
Unrealized Losses
Less Than 12 Months	10,196	10,309
12 Months or Longer	2,622	7,344
Total	$ 12,818	$ 17,653
MBSs
Securities Available-for-Sale
Number of Securities | security	73	68
Fair Value
Less Than 12 Months	$ 287,409	$ 221,174
12 Months or Longer	21,101	77,780
Total	308,510	298,954
Unrealized Losses
Less Than 12 Months	4,235	4,726
12 Months or Longer	409	1,154
Total	$ 4,644	$ 5,880
Municipal securities
Securities Available-for-Sale
Number of Securities | security	141	380
Fair Value
Less Than 12 Months	$ 58,746	$ 133,957
12 Months or Longer	3,623	29,280
Total	62,369	163,237
Unrealized Losses
Less Than 12 Months	868	3,059
12 Months or Longer	82	659
Total	$ 950	$ 3,718
CDOs
Securities Available-for-Sale
Number of Securities | security	7	7
Fair Value
Less Than 12 Months	$ 0	$ 0
12 Months or Longer	30,744	30,592
Total	30,744	30,592
Unrealized Losses
Less Than 12 Months	0	0
12 Months or Longer	14,565	14,682
Total	$ 14,565	$ 14,682
Equity securities
Securities Available-for-Sale
Number of Securities | security	2	2
Fair Value
Less Than 12 Months	$ 0	$ 404
12 Months or Longer	6,778	2,319
Total	6,778	2,723
Unrealized Losses
Less Than 12 Months	0	201
12 Months or Longer	233	86
Total	$ 233	$ 287
Municipal securities
Securities Held-to-Maturity
Number of Securities | security	11	14
Fair Value
Less Than 12 Months	$ 0	$ 0
12 Months or Longer	14,899	18,212
Total	14,899	18,212
Unrealized Losses
Less Than 12 Months	0	0
12 Months or Longer	2,454	4,079
Total	$ 2,454	$ 4,079

Loans (Details) - Loan Portfoli

Loans (Details) - Loan Portfolio - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 10,232,159	$ 8,254,145
Deferred loan fees included in total loans	4,375	3,838
Overdrawn demand deposits included in total loans	7,946	7,836
Commercial, industrial, and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	3,844,172	3,217,154
Commercial, industrial, and agricultural | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,410,748	2,827,658
Total Loans	3,410,748	2,827,658
Commercial, industrial, and agricultural | Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	433,424	389,496
Total Loans	433,424	389,496
Commercial real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	4,592,663	3,627,087
Total Loans	4,592,663	3,627,087
Commercial real estate loans | Office, retail, and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,983,802	1,581,967
Total Loans	1,983,802	1,581,967
Commercial real estate loans | Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	681,032	614,052
Total Loans	681,032	614,052
Commercial real estate loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	543,892	451,540
Total Loans	543,892	451,540
Commercial real estate loans | Other commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,383,937	979,528
Total Loans	1,383,937	979,528
Total corporate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	8,436,835	6,844,241
Total Loans	8,436,835	6,844,241
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,795,324	1,409,904
Total Loans	1,795,324	1,409,904
Consumer loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	865,656	747,983
Total Loans	865,656	747,983
Consumer loans | 1-4 family mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	614,818	423,922
Total Loans	614,818	423,922
Consumer loans | Installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	314,850	237,999
Total Loans	$ 314,850	$ 237,999

Loans (Details) - Loans Sales

Loans (Details) - Loans Sales - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total net gains on loan sales		$ 1,879	$ 1,680	$ 3,293	$ 2,965
Corporate loan sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales		19,569	14,271	34,937	23,859
Less book value of loans sold		19,123	13,760	34,240	22,890
Total net gains on loan sales	[1]	446	511	697	969
1-4 family mortgage loan sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales		60,894	53,258	116,655	92,765
Less book value of loans sold		59,461	52,089	114,059	90,769
Total net gains on loan sales	[2]	$ 1,433	$ 1,169	$ 2,596	$ 1,996
[1]	Net gains on corporate loan sales are included in other service charges, commissions, and fees in the Condensed Consolidated Statements of Income.
[2]	Net gains on 1-4 family mortgage loan sales are included in mortgage banking income in the Condensed Consolidated Statements of Income.

Acquired and Covered Loans (Det

Acquired and Covered Loans (Details) - Acquired Loans - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Acquired Loans (Details) - Acquired Loans [Line Items]
Non-PCI	[1]	$ 1,885,413	$ 628,718
Total	[1]	2,054,022	690,385
Acquired loans
Acquired Loans (Details) - Acquired Loans [Line Items]
Non-PCI	[1]	1,871,576	613,339
Total	[1]	2,032,798	667,111
Covered loans
Acquired Loans (Details) - Acquired Loans [Line Items]
Non-PCI	[1]	13,837	15,379
Total	[1]	21,224	23,274
Receivables acquired with deteriorated credit quality
Acquired Loans (Details) - Acquired Loans [Line Items]
PCI	[1]	168,609	61,667
Receivables acquired with deteriorated credit quality | Acquired loans
Acquired Loans (Details) - Acquired Loans [Line Items]
PCI	[1]	161,222	53,772
Receivables acquired with deteriorated credit quality | Covered loans
Acquired Loans (Details) - Acquired Loans [Line Items]
PCI	[1]	$ 7,387	$ 7,895
[1]	Included in loans in the Consolidated Statements of Condition.

Acquired and Covered Loans (D50

Acquired and Covered Loans (Details) - Narrative - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Acquired Loans [Abstract]
Outstanding balance of PCI loans	$ 242,000		$ 242,000		$ 84,800
Renewed non-purchased credit impaired loans	233,600		233,600		$ 117,600
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Accretion on acquired loans	3,888	$ 2,303	7,843	$ 3,849
Acquired and Covered Receivables
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Accretion on acquired loans	$ 8,800	$ 4,900	$ 20,100	$ 7,400

Acquired and Covered Loans (D51

Acquired and Covered Loans (Details) - Changes in FDIC Indemnification Asset - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
FDIC Indemnification Asset [Roll Forward]
Beginning balance	$ 4,220	$ 5,680	$ 4,522	$ 3,903
Amortization	(302)	(302)	(604)	(582)
Change in expected reimbursements from the FDIC for changes in expected credit losses	(202)	(475)	(530)	(259)
Net payments to the FDIC	202	268	530	2,109
Ending balance	$ 3,918	$ 5,171	$ 3,918	$ 5,171

Acquired and Covered Loans (D52

Acquired and Covered Loans (Details) - Changes in Accretable Yield - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Changes in Accretable Yield [Roll Forward]
Beginning balances		$ 41,249	$ 27,258	$ 19,385	$ 24,912
Additions		0	0	27,316	3,981
Accretion		(3,888)	(2,303)	(7,843)	(3,849)
Other	[1]	2,509	127	1,012	38
Ending balance		$ 39,870	$ 25,082	$ 39,870	$ 25,082
[1]	Increases represent a rise in the expected future cash flows to be collected over the remaining estimated life of the underlying portfolio.

Past Due Loans, Allowance For53

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Aging Analysis of Past Due Loans and Non-Performing Loans by Class - USD ($)		Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	$ 10,191,558,000	$ 8,204,440,000
Total Past Due		40,601,000	49,705,000
Total Loans		10,232,159,000	8,254,145,000
Non- accrual	[2]	79,196,000	59,289,000
90 Days or More Past Due, Still Accruing Interest		2,059,000	5,009,000
30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		22,329,000	22,923,000
90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		18,272,000	26,782,000
Commercial, industrial, and agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans		3,844,172,000	3,217,154,000
Commercial, industrial, and agricultural | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	3,399,763,000	2,816,442,000
Total Past Due		10,985,000	11,216,000
Total Loans		3,410,748,000	2,827,658,000
Non- accrual	[2]	51,400,000	29,938,000
90 Days or More Past Due, Still Accruing Interest		1,550,000	374,000
Commercial, industrial, and agricultural | Agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	432,672,000	388,596,000
Total Past Due		752,000	900,000
Total Loans		433,424,000	389,496,000
Non- accrual	[2]	387,000	181,000
90 Days or More Past Due, Still Accruing Interest		0	736,000
Commercial, industrial, and agricultural | 30-89 Days Past Due | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		8,282,000	6,426,000
Commercial, industrial, and agricultural | 30-89 Days Past Due | Agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		379,000	0
Commercial, industrial, and agricultural | 90 Days or More Past Due | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		2,703,000	4,790,000
Commercial, industrial, and agricultural | 90 Days or More Past Due | Agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		373,000	900,000
Commercial real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	4,574,960,000	3,601,955,000
Total Past Due		17,703,000	25,132,000
Total Loans		4,592,663,000	3,627,087,000
Non- accrual	[2]	19,122,000	20,766,000
90 Days or More Past Due, Still Accruing Interest		173,000	3,259,000
Commercial real estate loans | Office, retail, and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	1,973,608,000	1,564,007,000
Total Past Due		10,194,000	17,960,000
Total Loans		1,983,802,000	1,581,967,000
Non- accrual	[2]	15,031,000	17,277,000
90 Days or More Past Due, Still Accruing Interest		0	1,129,000
Commercial real estate loans | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	679,795,000	612,446,000
Total Past Due		1,237,000	1,606,000
Total Loans		681,032,000	614,052,000
Non- accrual	[2]	158,000	311,000
90 Days or More Past Due, Still Accruing Interest		109,000	604,000
Commercial real estate loans | Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	543,023,000	450,927,000
Total Past Due		869,000	613,000
Total Loans		543,892,000	451,540,000
Non- accrual	[2]	197,000	286,000
90 Days or More Past Due, Still Accruing Interest		0	0
Commercial real estate loans | Other commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	1,378,534,000	974,575,000
Total Past Due		5,403,000	4,953,000
Total Loans		1,383,937,000	979,528,000
Non- accrual	[2]	3,736,000	2,892,000
90 Days or More Past Due, Still Accruing Interest		64,000	1,526,000
Commercial real estate loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		6,013,000	7,824,000
Commercial real estate loans | 30-89 Days Past Due | Office, retail, and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		1,847,000	5,327,000
Commercial real estate loans | 30-89 Days Past Due | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		1,128,000	858,000
Commercial real estate loans | 30-89 Days Past Due | Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		675,000	332,000
Commercial real estate loans | 30-89 Days Past Due | Other commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		2,363,000	1,307,000
Commercial real estate loans | 90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		11,690,000	17,308,000
Commercial real estate loans | 90 Days or More Past Due | Office, retail, and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		8,347,000	12,633,000
Commercial real estate loans | 90 Days or More Past Due | Multi-family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		109,000	748,000
Commercial real estate loans | 90 Days or More Past Due | Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		194,000	281,000
Commercial real estate loans | 90 Days or More Past Due | Other commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		3,040,000	3,646,000
Total corporate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	8,407,395,000	6,806,993,000
Total Past Due		29,440,000	37,248,000
Total Loans		8,436,835,000	6,844,241,000
Non- accrual	[2]	70,909,000	50,885,000
90 Days or More Past Due, Still Accruing Interest		1,723,000	4,369,000
Total corporate loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		14,674,000	14,250,000
Total corporate loans | 90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		14,766,000	22,998,000
Consumer loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	1,784,163,000	1,397,447,000
Total Past Due		11,161,000	12,457,000
Total Loans		1,795,324,000	1,409,904,000
Non- accrual	[2]	8,287,000	8,404,000
90 Days or More Past Due, Still Accruing Interest		336,000	640,000
Consumer loans | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	859,362,000	740,919,000
Total Past Due		6,294,000	7,064,000
Total Loans		865,656,000	747,983,000
Non- accrual	[2]	5,126,000	5,465,000
90 Days or More Past Due, Still Accruing Interest		41,000	109,000
Consumer loans | 1-4 family mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	612,669,000	420,264,000
Total Past Due		2,149,000	3,658,000
Total Loans		614,818,000	423,922,000
Non- accrual	[2]	3,161,000	2,939,000
90 Days or More Past Due, Still Accruing Interest		0	272,000
Consumer loans | Installment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	[1]	312,132,000	236,264,000
Total Past Due		2,718,000	1,735,000
Total Loans		314,850,000	237,999,000
Non- accrual	[2]	0	0
90 Days or More Past Due, Still Accruing Interest		295,000	259,000
Consumer loans | 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		7,655,000	8,673,000
Consumer loans | 30-89 Days Past Due | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		4,083,000	4,545,000
Consumer loans | 30-89 Days Past Due | 1-4 family mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		1,149,000	2,652,000
Consumer loans | 30-89 Days Past Due | Installment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		2,423,000	1,476,000
Consumer loans | 90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		3,506,000	3,784,000
Consumer loans | 90 Days or More Past Due | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		2,211,000	2,519,000
Consumer loans | 90 Days or More Past Due | 1-4 family mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		1,000,000	1,006,000
Consumer loans | 90 Days or More Past Due | Installment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		295,000	259,000
Receivables acquired with deteriorated credit quality
Financing Receivable, Recorded Investment, Past Due [Line Items]
PCI	[3]	168,609,000	61,667,000
Receivables acquired with deteriorated credit quality | Commercial, industrial, and agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
PCI		30,125,000	3,182,000
Receivables acquired with deteriorated credit quality | Commercial real estate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
PCI		115,431,000	41,461,000
Receivables acquired with deteriorated credit quality | Total corporate loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
PCI		145,556,000	44,643,000
Receivables acquired with deteriorated credit quality | Consumer loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
PCI		23,053,000	17,024,000
Receivables acquired with deteriorated credit quality | Non-accrual
Financing Receivable, Recorded Investment, Past Due [Line Items]
PCI		$ 243,000	$ 682,000
[1]	PCI loans with an accretable yield are considered current.
[2]	Includes PCI loans of $243,000 and $682,000 as of June 30, 2017 and December 31, 2016, respectively, which no longer have an accretable yield as estimates of expected future cash flows have decreased since the acquisition due to credit deterioration.
[3]	Included in loans in the Consolidated Statements of Condition.

Past Due Loans, Allowance For54

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Allowance for Credit Losses - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	$ 89,163	$ 78,375	$ 87,083	$ 74,855
Charge-offs	(4,859)	(6,133)	(11,137)	(11,322)
Recoveries	828	1,003	4,268	2,119
Net charge-offs	(4,031)	(5,130)	(6,869)	(9,203)
Provision for loan losses and other	8,239	8,260	13,157	15,853
Ending balance	93,371	81,505	93,371	81,505
Reserve for Unfunded Commitments
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	1,000	1,225	1,000	1,225
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Net charge-offs	0	0	0	0
Provision for loan losses and other	0	175	0	175
Ending balance	1,000	1,400	1,000	1,400
Commercial, Industrial, and Agricultural
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	41,786	37,736	40,709	37,074
Charge-offs	(2,957)	(2,026)	(7,031)	(3,924)
Recoveries	400	576	2,066	1,078
Net charge-offs	(2,557)	(1,450)	(4,965)	(2,846)
Provision for loan losses and other	7,042	3,798	10,527	5,856
Ending balance	46,271	40,084	46,271	40,084
Commercial Real Estate Loans
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance			32,039
Ending balance	29,500		29,500
Commercial Real Estate Loans | Office, Retail, and Industrial
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	17,701	14,420	17,595	13,124
Charge-offs	0	(1,641)	(127)	(2,165)
Recoveries	8	8	983	111
Net charge-offs	8	(1,633)	856	(2,054)
Provision for loan losses and other	(2,701)	198	(3,443)	1,915
Ending balance	15,008	12,985	15,008	12,985
Commercial Real Estate Loans | Multi-family
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	2,860	2,547	3,261	2,469
Charge-offs	0	(84)	0	(288)
Recoveries	6	1	34	26
Net charge-offs	6	(83)	34	(262)
Provision for loan losses and other	53	469	(376)	726
Ending balance	2,919	2,933	2,919	2,933
Commercial Real Estate Loans | Construction
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	4,110	2,433	3,444	1,440
Charge-offs	(39)	(8)	(44)	(134)
Recoveries	12	20	239	35
Net charge-offs	(27)	12	195	(99)
Provision for loan losses and other	11	(206)	455	898
Ending balance	4,094	2,239	4,094	2,239
Commercial Real Estate Loans | Other Commercial Real Estate
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	6,922	6,588	7,739	6,109
Charge-offs	(307)	(879)	(715)	(2,324)
Recoveries	79	69	180	220
Net charge-offs	(228)	(810)	(535)	(2,104)
Provision for loan losses and other	785	1,714	275	3,487
Ending balance	7,479	7,492	7,479	7,492
Consumer Loans
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance			13,335
Ending balance	16,600		16,600
Consumer Loans | Consumer Loans
Allowance for Credit Losses by Portfolio Segment [Roll Forward]
Beginning balance	14,784	13,426	13,335	13,414
Charge-offs	(1,556)	(1,495)	(3,220)	(2,487)
Recoveries	323	329	766	649
Net charge-offs	(1,233)	(1,166)	(2,454)	(1,838)
Provision for loan losses and other	3,049	2,112	5,719	2,796
Ending balance	$ 16,600	$ 14,372	$ 16,600	$ 14,372

Past Due Loans, Allowance For55

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Loans and Related Allowance for Credit Losses by Portfolio Segment - USD ($) $ in Thousands		Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		$ 66,872		$ 42,650
Loans Collectively Evaluated for Impairment		9,996,678		8,149,828
Loans		10,232,159		8,254,145
Allowance for Credit Losses Individually Evaluated for Impairment		5,238		525
Allowance for Credit Losses Collectively Evaluated for Impairment		83,068		81,864
Total Allowance for Credit Losses		93,371	$ 89,163	87,083	$ 81,505	$ 78,375	$ 74,855
Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI	[1]	168,609		61,667
Total Allowance for Credit Losses		5,065		4,694
Reserve for unfunded commitments
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		0		0
Loans Collectively Evaluated for Impairment		0		0
Loans		0		0
Allowance for Credit Losses Individually Evaluated for Impairment		0		0
Allowance for Credit Losses Collectively Evaluated for Impairment		1,000		1,000
Total Allowance for Credit Losses		1,000		1,000
Reserve for unfunded commitments | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		0		0
Total Allowance for Credit Losses		0		0
Commercial, industrial, and agricultural
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		50,521		24,645
Loans Collectively Evaluated for Impairment		3,763,526		3,189,327
Loans		3,844,172		3,217,154
Allowance for Credit Losses Individually Evaluated for Impairment		4,859		507
Allowance for Credit Losses Collectively Evaluated for Impairment		40,922		39,554
Total Allowance for Credit Losses		46,271	$ 41,786	40,709	$ 40,084	$ 37,736	$ 37,074
Commercial, industrial, and agricultural | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		30,125		3,182
Total Allowance for Credit Losses		490		648
Commercial real estate loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		16,351		18,005
Loans Collectively Evaluated for Impairment		4,460,881		3,567,621
Loans		4,592,663		3,627,087
Allowance for Credit Losses Individually Evaluated for Impairment		379		18
Allowance for Credit Losses Collectively Evaluated for Impairment		25,973		29,100
Total Allowance for Credit Losses		29,500		32,039
Commercial real estate loans | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		115,431		41,461
Total Allowance for Credit Losses		3,148		2,921
Commercial real estate loans | Office, retail, and industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		13,781		16,287
Loans Collectively Evaluated for Impairment		1,951,097		1,553,234
Loans		1,983,802		1,581,967
Allowance for Credit Losses Individually Evaluated for Impairment		379		0
Allowance for Credit Losses Collectively Evaluated for Impairment		12,970		16,148
Total Allowance for Credit Losses		15,008		17,595
Commercial real estate loans | Office, retail, and industrial | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		18,924		12,446
Total Allowance for Credit Losses		1,659		1,447
Commercial real estate loans | Multi-family
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		396		398
Loans Collectively Evaluated for Impairment		666,237		601,429
Loans		681,032		614,052
Allowance for Credit Losses Individually Evaluated for Impairment		0		0
Allowance for Credit Losses Collectively Evaluated for Impairment		2,833		3,059
Total Allowance for Credit Losses		2,919		3,261
Commercial real estate loans | Multi-family | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		14,399		12,225
Total Allowance for Credit Losses		86		202
Commercial real estate loans | Construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		0		34
Loans Collectively Evaluated for Impairment		528,570		447,058
Loans		543,892		451,540
Allowance for Credit Losses Individually Evaluated for Impairment		0		0
Allowance for Credit Losses Collectively Evaluated for Impairment		3,945		3,280
Total Allowance for Credit Losses		4,094		3,444
Commercial real estate loans | Construction | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		15,322		4,448
Total Allowance for Credit Losses		149		164
Commercial real estate loans | Other commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		2,174		1,286
Loans Collectively Evaluated for Impairment		1,314,977		965,900
Loans		1,383,937		979,528
Allowance for Credit Losses Individually Evaluated for Impairment		0		18
Allowance for Credit Losses Collectively Evaluated for Impairment		6,225		6,613
Total Allowance for Credit Losses		7,479		7,739
Commercial real estate loans | Other commercial real estate | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		66,786		12,342
Total Allowance for Credit Losses		1,254		1,108
Total corporate loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		66,872		42,650
Loans Collectively Evaluated for Impairment		8,224,407		6,756,948
Loans		8,436,835		6,844,241
Allowance for Credit Losses Individually Evaluated for Impairment		5,238		525
Allowance for Credit Losses Collectively Evaluated for Impairment		66,895		68,654
Total Allowance for Credit Losses		75,771		72,748
Total corporate loans | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		145,556		44,643
Total Allowance for Credit Losses		3,638		3,569
Consumer loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans Individually Evaluated for Impairment		0		0
Loans Collectively Evaluated for Impairment		1,772,271		1,392,880
Loans		1,795,324		1,409,904
Allowance for Credit Losses Individually Evaluated for Impairment		0		0
Allowance for Credit Losses Collectively Evaluated for Impairment		15,173		12,210
Total Allowance for Credit Losses		16,600		13,335
Consumer loans | Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
PCI		23,053		17,024
Total Allowance for Credit Losses		$ 1,427		$ 1,125
[1]	Included in loans in the Consolidated Statements of Condition.

Past Due Loans, Allowance For56

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Impaired Loans Individually Evaluated by Class - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	$ 29,189	$ 29,314
Recorded Investment in Loans with a Specific Reserve	37,683	13,336
Unpaid Principal Balance	74,807	53,144
Specific Reserve	5,238	525
Commercial, industrial, and agricultural | Commercial and industrial
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	16,215	11,579
Recorded Investment in Loans with a Specific Reserve	34,027	13,066
Unpaid Principal Balance	53,545	29,514
Specific Reserve	4,859	507
Commercial, industrial, and agricultural | Agricultural
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	279	0
Recorded Investment in Loans with a Specific Reserve	0	0
Unpaid Principal Balance	1,629	0
Specific Reserve	0	0
Commercial real estate loans
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	12,695	17,735
Recorded Investment in Loans with a Specific Reserve	3,656	270
Unpaid Principal Balance	19,633	23,630
Specific Reserve	379	18
Commercial real estate loans | Office, retail, and industrial
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	10,125	16,287
Recorded Investment in Loans with a Specific Reserve	3,656	0
Unpaid Principal Balance	16,966	21,057
Specific Reserve	379	0
Commercial real estate loans | Multi-family
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	396	398
Recorded Investment in Loans with a Specific Reserve	0	0
Unpaid Principal Balance	396	398
Specific Reserve	0	0
Commercial real estate loans | Construction
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	0	34
Recorded Investment in Loans with a Specific Reserve	0	0
Unpaid Principal Balance	0	34
Specific Reserve	0	0
Commercial real estate loans | Other commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment in Loans with No Specific Reserve	2,174	1,016
Recorded Investment in Loans with a Specific Reserve	0	270
Unpaid Principal Balance	2,271	2,141
Specific Reserve	$ 0	$ 18

Past Due Loans, Allowance For57

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Impaired Loans Individually Evaluated by Class (Continued) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		$ 50,687	$ 20,024	$ 48,006	$ 17,908
Interest Income Recognized	[1]	519	94	1,002	200
Commercial, industrial, and agricultural | Commercial and industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		33,648	3,236	30,647	3,114
Interest Income Recognized	[1]	342	12	556	50
Commercial, industrial, and agricultural | Agricultural
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		697	0	464	0
Interest Income Recognized	[1]	0	0	0	0
Commercial real estate loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		16,342	16,788	16,895	14,794
Interest Income Recognized	[1]	177	82	446	150
Commercial real estate loans | Office, retail, and industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		13,612	12,712	14,503	10,529
Interest Income Recognized	[1]	169	29	262	77
Commercial real estate loans | Multi-family
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		396	401	397	534
Interest Income Recognized	[1]	0	0	28	1
Commercial real estate loans | Construction
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		0	34	11	82
Interest Income Recognized	[1]	0	0	136	0
Commercial real estate loans | Other commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment		2,334	3,641	1,984	3,649
Interest Income Recognized	[1]	$ 8	$ 53	$ 20	$ 72
[1]	Recorded using the cash basis of accounting.

Past Due Loans, Allowance For58

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Credit Quality Indicators by Class - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Accruing		$ 2,029	$ 2,291
Special Mention and Substandard Loans
Financing Receivable, Recorded Investment [Line Items]
Accruing		669	834
Total corporate loans
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		8,436,835	6,843,914
Total corporate loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		8,040,671	6,493,630
Total corporate loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	144,537	159,675
Total corporate loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	180,718	139,724
Total corporate loans | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	70,909	50,885
Commercial, industrial, and agricultural | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		3,410,748	2,827,658
Accruing		273	281
Commercial, industrial, and agricultural | Commercial and industrial | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		3,199,001	2,638,833
Commercial, industrial, and agricultural | Commercial and industrial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	67,252	92,340
Commercial, industrial, and agricultural | Commercial and industrial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	93,095	66,547
Commercial, industrial, and agricultural | Commercial and industrial | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	51,400	29,938
Commercial, industrial, and agricultural | Agricultural
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		433,424	389,496
Accruing		0	0
Commercial, industrial, and agricultural | Agricultural | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		409,969	366,382
Commercial, industrial, and agricultural | Agricultural | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	14,464	17,039
Commercial, industrial, and agricultural | Agricultural | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	8,604	5,894
Commercial, industrial, and agricultural | Agricultural | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	387	181
Commercial real estate loans
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		4,592,663	3,626,760
Accruing		776	1,009
Commercial real estate loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		4,431,701	3,488,415
Commercial real estate loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	62,821	50,296
Commercial real estate loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	79,019	67,283
Commercial real estate loans | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	19,122	20,766
Commercial real estate loans | Office, retail, and industrial
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		1,983,802	1,581,827
Accruing		0	155
Commercial real estate loans | Office, retail, and industrial | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		1,896,327	1,491,030
Commercial real estate loans | Office, retail, and industrial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	27,894	34,007
Commercial real estate loans | Office, retail, and industrial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	44,550	39,513
Commercial real estate loans | Office, retail, and industrial | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	15,031	17,277
Commercial real estate loans | Multi-family
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		681,032	614,034
Accruing		579	586
Commercial real estate loans | Multi-family | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		673,946	607,324
Commercial real estate loans | Multi-family | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	5,051	4,370
Commercial real estate loans | Multi-family | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	1,877	2,029
Commercial real estate loans | Multi-family | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	158	311
Commercial real estate loans | Construction
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		543,892	451,540
Accruing		0	0
Commercial real estate loans | Construction | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		523,046	438,946
Commercial real estate loans | Construction | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	8,739	111
Commercial real estate loans | Construction | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	11,910	12,197
Commercial real estate loans | Construction | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	197	286
Commercial real estate loans | Other commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		1,383,937	979,359
Accruing		197	268
Commercial real estate loans | Other commercial real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class		1,338,382	951,115
Commercial real estate loans | Other commercial real estate | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[1],[2]	21,137	11,808
Commercial real estate loans | Other commercial real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[2],[3]	20,682	13,544
Commercial real estate loans | Other commercial real estate | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Credit Quality Indicators by Class	[4]	$ 3,736	$ 2,892
[1]	Loans categorized as special mention exhibit potential weaknesses that require the close attention of management since these potential weaknesses may result in the deterioration of repayment prospects in the future.
[2]	Total special mention and substandard loans includes accruing TDRs of $669,000 as of June 30, 2017 and $834,000 as of December 31, 2016.
[3]	Loans categorized as substandard exhibit well-defined weaknesses that may jeopardize the liquidation of the debt. These loans continue to accrue interest because they are well-secured and collection of principal and interest is expected within a reasonable time.
[4]	Loans categorized as non-accrual exhibit well-defined weaknesses that may jeopardize the liquidation of the debt or result in a loss if the deficiencies are not corrected.

Past Due Loans, Allowance For59

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Credit Quality Indicators by Class (Continued) - Consumer loans - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	$ 1,795,324	$ 1,386,957
Performing
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	1,787,037	1,379,032
Non-accrual
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	8,287	7,925
Home equity
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	865,656	732,604
Home equity | Performing
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	860,530	727,618
Home equity | Non-accrual
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	5,126	4,986
1-4 family mortgages
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	614,818	416,354
1-4 family mortgages | Performing
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	611,657	413,415
1-4 family mortgages | Non-accrual
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	3,161	2,939
Installment
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	314,850	237,999
Installment | Performing
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	314,850	237,999
Installment | Non-accrual
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - Credit Quality Indicators by Class, Excluding Covered Loans (Continued) [Line Items]
Credit Quality Indicators by Class	$ 0	$ 0

Past Due Loans, Allowance For60

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - TDRs By Class - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		$ 2,029	$ 2,291
Non-accrual	[1]	3,036	6,297
Total		5,065	8,588	$ 4,181
Commercial, industrial, and agricultural | Commercial and industrial
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		273	281
Non-accrual	[1]	891	150
Total		1,164	431
Commercial, industrial, and agricultural | Agricultural
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	0
Non-accrual	[1]	0	0
Total		0	0
Commercial real estate loans
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		776	1,009
Non-accrual	[1]	1,018	4,949
Total		1,794	5,958
Commercial real estate loans | Office, retail, and industrial
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	155
Non-accrual	[1]	860	4,733
Total		860	4,888
Commercial real estate loans | Multi-family
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		579	586
Non-accrual	[1]	158	168
Total		737	754
Commercial real estate loans | Construction
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	0
Non-accrual	[1]	0	0
Total		0	0
Commercial real estate loans | Other commercial real estate
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		197	268
Non-accrual	[1]	0	48
Total		197	316
Total corporate loans
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		1,049	1,290
Non-accrual	[1]	1,909	5,099
Total		2,958	6,389
Consumer loans
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		980	1,001
Non-accrual	[1]	1,127	1,198
Total		2,107	2,199
Consumer loans | Home equity
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		168	177
Non-accrual	[1]	771	820
Total		939	997
Consumer loans | 1-4 family mortgages
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		812	824
Non-accrual	[1]	356	378
Total		1,168	1,202
Consumer loans | Installment
Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Details) - TDRs By Class [Line Items]
Accruing		0	0
Non-accrual	[1]	0	0
Total		$ 0	$ 0
[1]	These TDRs are included in non-accrual loans in the preceding tables.

Past Due Loans, Allowance For61

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - Narrative - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Valuation allowance on TDR loans	$ 0	$ 0
Commitments to lend additional funds on TDRs loans	$ 0	$ 0

Past Due Loans, Allowance For62

Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRS (Details) - TDR Rollforward - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Troubled Debt Restructuring Activity Rollforward [Roll Forward]
Beginning balance			$ 8,588
Ending balance	$ 5,065	$ 4,181	5,065	$ 4,181
Accruing
Troubled Debt Restructuring Activity Rollforward [Roll Forward]
Beginning balance	2,112	2,702	2,291	2,743
Additions	0	0	922	0
Net payments received	(83)	(28)	(107)	(69)
Net transfers to non-accrual	0	(183)	(1,077)	(183)
Ending balance	2,029	2,491	2,029	2,491
Non-accrual
Troubled Debt Restructuring Activity Rollforward [Roll Forward]
Beginning balance	3,112	2,268	6,297	2,324
Net payments received	(75)	(522)	(4,225)	(578)
Charge-offs	(1)	(239)	(113)	(239)
Net transfers from accruing	0	183	1,077	183
Ending balance	$ 3,036	$ 1,690	$ 3,036	$ 1,690

Premises, Furniture, and Equi63

Premises, Furniture, and Equipment (Details) - Premises, Furniture, and Equipment - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Land	$ 31,623	$ 18,304
Premises	139,137	94,369
Furniture and equipment	135,328	105,859
Total cost	306,088	218,532
Accumulated depreciation	(182,075)	(140,030)
Net book value of premises, furniture, and equipment	124,013	78,502
Assets held-for-sale	11,732	4,075
Total premises, furniture, and equipment	$ 135,745	$ 82,577

Premises, Furniture, and Equi64

Premises, Furniture, and Equipment (Details) - Narrative $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)renewal_optionretail_branch
Property, Plant and Equipment [Line Items]
Aggregate cash purchase price					$ 150.3
Number of branches sold | retail_branch					55
Net book value of properties					$ 58.8
Initial term of lease for sale-leaseback transaction					14 years
Number of lease renewal options | renewal_option					5
Pre-tax gain on sale-leaseback transaction					$ 88
Deferred gain, net	$ 78.1		$ 78.1		$ 82.5
Depreciation of premises, furniture, and equipment	$ 3.5	$ 3.4	$ 7	$ 6.6
Five Year Renewal Period
Property, Plant and Equipment [Line Items]
Renewal lease periods for sale-leaseback transactions					5 years

Premises, Furniture, and Equi65

Premises, Furniture, and Equipment (Details) - Operating Leases $ in Thousands	Jun. 30, 2017USD ($)
Property, Plant and Equipment [Abstract]
One year or less	$ 18,383
After one year to two years	16,751
After two years to three years	16,606
After three years to four years	16,268
After four years to five years	16,119
After five years	120,356
Total minimum lease payments	$ 204,483

Premises, Furniture, and Equi66

Premises, Furniture, and Equipment (Details) - Accretion of Operating Leases $ in Thousands	Jun. 30, 2017USD ($)
Property, Plant and Equipment [Abstract]
One year or less	$ 1,095
After one year to two years	791
After two years to three years	648
After three years to four years	648
After four years to five years	648
After five years	3,673
Total accretion	$ 7,503

Premises, Furniture, and Equi67

Premises, Furniture, and Equipment (Details) - Rental Expense - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Property, Plant and Equipment [Abstract]
Lease expense charged to operations		$ 4,721	$ 1,773	$ 9,280	$ 3,500
Accretion of operating lease intangible	[1]	(295)	(295)	(590)	(581)
Accretion of deferred gain on sale-leaseback transaction	[1]	(1,473)	0	(2,946)	0
Rental income from premises leased to others	[1]	(169)	(128)	(350)	(286)
Net operating lease expense		$ 2,784	$ 1,350	$ 5,394	$ 2,633
[1]	Included as reductions to net occupancy and equipment expense in the Condensed Consolidated Statements of Income.

Goodwill and Other Intangible68

Goodwill and Other Intangible Assets (Details) - Changes in Carrying Amount of Goodwill - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Goodwill [Roll Forward]
Beginning balance	$ 691,572	$ 339,768	$ 340,879	$ 319,007
Acquisitions	(45)	1,745	350,648	22,506
Ending balance	$ 691,527	$ 341,513	$ 691,527	$ 341,513

Goodwill and Other Intangible69

Goodwill and Other Intangible Assets (Details) - Other Intangible Assets - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Finite-lived Intangible Assets [Roll Forward]
Balance at the beginning of the year, gross	$ 58,959	$ 48,550
Balance at the beginning of the year, accumulated amortization	32,962	28,280
Balance at the beginning of the year, net	25,997	20,270
Additions	39,017	10,409
Amortization expense	4,128	2,230
Balance at the end of the year, gross	97,976	58,959
Balance at the end of the year, accumulated amortization	37,090	30,510
Balance at the end of the year, net	$ 60,886	$ 28,449

Goodwill and Other Intangible70

Goodwill and Other Intangible Assets (Details) - Amortization of Other Intangible Assets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
2,018	$ 7,332
2,019	7,086
2,020	7,055
2,021	6,986
2,022	6,908
2023 and thereafter	25,519
Total	$ 60,886	$ 25,997	$ 28,449	$ 20,270

Deposits (Details) - Summary of

Deposits (Details) - Summary of Deposits - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Deposits [Abstract]
Demand deposits	$ 3,525,905	$ 2,766,748
Savings deposits	2,059,833	1,615,833
NOW accounts	1,970,036	1,675,421
Money market deposits	1,905,402	1,577,316
Time deposits less than $100,000	894,530	755,558
Time deposits greater than $100,000	644,014	437,727
Total deposits	$ 10,999,720	$ 8,828,603

Material Transactions Affecti72

Material Transactions Affecting Stockholders' Equity (Details) - $ / shares	May 17, 2017	Jun. 30, 2017	Dec. 31, 2016
Equity [Abstract]
Increase to authorized common stock (in shares)	100,000,000
Increase to common and preferred shares authorized (in shares)	251,000,000
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000	1,000,000
Common stock, shares authorized (in shares)	250,000,000	250,000,000	150,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01

Earnings Per Common Share (Deta

Earnings Per Common Share (Details) - Basic and Diluted Earnings Per Common Share - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Net income		$ 34,950	$ 25,267	$ 57,805	$ 43,229
Net income applicable to non-vested restricted shares		(336)	(290)	(570)	(502)
Net income applicable to common shares		$ 34,614	$ 24,977	$ 57,235	$ 42,727
Weighted-average common shares outstanding:
Weighted-average common shares outstanding (basic) (in Shares)		101,743	80,383	101,081	79,182
Dilutive effect of common stock equivalents (in Shares)		20	13	20	12
Weighted-average diluted common shares outstanding (in Shares)		101,763	80,396	101,101	79,194
Basic EPS (in dollars per share)		$ 0.34	$ 0.31	$ 0.57	$ 0.54
Diluted EPS (in dollars per share)		$ 0.34	$ 0.31	$ 0.57	$ 0.54
Anti-dilutive shares not included in the computation of diluted EPS (in Shares)	[1]	195	469	269	539
[1]	This amount represents outstanding stock options for which the exercise price is greater than the average market price of the Company's common stock.

Derivative Instruments and He74

Derivative Instruments and Hedging Activities (Details) - Fair Value Hedges - Fair Value Hedging - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
		Jun. 30, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross notional amount outstanding		$ 5,708	$ 5,958
Derivative liability fair value		$ (186)	$ (282)
Weighted-average interest rate received		3.08%	2.63%
Weighted-average interest rate paid		5.96%	5.96%
Weighted-average maturity (in years)		1 year 4 months 7 days	1 year 10 months 2 days
Fair value of derivative	[1]	$ 197	$ 296
[1]	This amount represents the fair value if credit risk related contingent features were triggered.

Derivative Instruments and He75

Derivative Instruments and Hedging Activities (Details) - Narrative - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Feb. 28, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Amount of variable rate loans hedged using interest rate swaps	$ 980,000		$ 980,000
Amount hedged of borrowed funds using forward starting interest rate swaps	980,000		980,000		$ 415,000
Amount to be hedged of borrowed funds using forward starting interest rate swaps	$ 565,000		$ 565,000
Weighted-average interest rate to be paid	1.96%		1.96%
Interest rate cash flow hedge loss (gain) to be reclassified during the next 12 months, net	$ 303		$ 303
Capital market products income	$ 2,217	$ 2,066	$ 3,593	$ 5,281
Portion of fair value of outstanding interest rate swaps covered by collateral agreements (percent)	100.00%		100.00%			100.00%

Derivative Instruments and He76

Derivative Instruments and Hedging Activities (Details) - Cash Flow Hedges - Cash Flow Hedging - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross notional amount outstanding	$ 1,960,000	$ 1,470,000
Derivative asset fair value	3,528	5,402
Derivative liability fair value	$ (7,627)	$ (7,390)
Weighted-average interest rate received	1.51%	1.37%
Weighted-average interest rate paid	1.40%	1.11%
Weighted-average maturity (in years)	2 years 9 months	2 years 9 months 28 days

Derivative Instruments and He77

Derivative Instruments and Hedging Activities (Details) - Other Derivative Instruments - Other Derivative Instruments - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Gross notional amount outstanding		$ 2,252,704	$ 1,656,612
Derivative asset fair value		17,370	13,478
Derivative liability fair value		(15,347)	(13,478)
Fair value of derivative	[1]	$ 15,605	$ 13,753
[1]	This amount represents the fair value if credit risk related contingent features were triggered.

Derivative Instruments and He78

Derivative Instruments and Hedging Activities (Details) - Offsetting Derivatives - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Assets
Gross amounts recognized		$ 20,898	$ 18,880
Less: amounts offset in the Consolidated Statements of Financial Condition		0	0
Net amount presented in the Consolidated Statements of Financial Condition	[1]	20,898	18,880
Offsetting derivative positions		(8,646)	(10,889)
Cash collateral pledged		0	0
Net credit exposure		12,252	7,991
Liabilities
Gross amounts recognized		23,160	21,150
Less: amounts offset in the Consolidated Statements of Financial Condition		0	0
Net amount presented in the Consolidated Statements of Financial Condition	[1]	23,160	21,150
Offsetting derivative positions		(8,646)	(10,889)
Cash collateral pledged		(14,514)	(10,261)
Net credit exposure		$ 0	$ 0
[1]	Included in other assets or other liabilities in the Consolidated Statements of Financial Condition.

Commitments, Guarantees, and 79

Commitments, Guarantees, and Contingent Liabilities (Details) - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Other Commitments [Line Items]
Letters of credit		$ 137,913	$ 100,430
Recourse on assets sold:
Unpaid principal balance of loans sold		185,182	187,158
Carrying value of recourse obligation	[1]	153	142
Commitments to extend credit
Other Commitments [Line Items]
Commercial, industrial, and agricultural		1,750,477	1,522,152
Commercial real estate		347,330	397,423
Home equity		508,295	426,384
Other commitments	[2]	248,320	214,943
Total commitments to extend credit		$ 2,854,422	$ 2,560,902
[1]	Included in other liabilities in the Consolidated Statements of Financial Condition.
[2]	Other commitments includes installment and overdraft protection program commitments.

Fair Value (Details) - Fair Val

Fair Value (Details) - Fair Value Measurements - USD ($) $ in Thousands		Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Trading securities:
Total trading securities		$ 19,545		$ 17,920
Securities Available-for-Sale
Securities available-for-sale, at fair value		1,908,248		1,919,450
Mortgage servicing rights (MSRs)		5,925	$ 6,245	6,120	$ 4,938	$ 5,022	$ 1,853
U.S. treasury securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		48,483		48,541
U.S. agency securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		175,058		183,637
MBSs
Securities Available-for-Sale
Securities available-for-sale, at fair value		373,660		332,655
Municipal securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		264,402		270,846
CDOs
Securities Available-for-Sale
Securities available-for-sale, at fair value		33,454		33,260
Equity securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		7,027		3,065
Recurring | Level 1
Trading securities:
Money market funds		1,717		1,645
Mutual funds		17,828		16,275
Total trading securities		19,545		17,920
Securities Available-for-Sale
Securities available-for-sale, at fair value		48,483		48,541
Mortgage servicing rights (MSRs)	[1]	0
Derivative assets	[1]	0		0
Liabilities:
Derivative liabilities	[2]	0		0
Recurring | Level 1 | U.S. treasury securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		48,483		48,541
Recurring | Level 1 | U.S. agency securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 1 | CMOs
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 1 | MBSs
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 1 | Municipal securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 1 | CDOs
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 1 | Equity securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 2
Trading securities:
Money market funds		0		0
Mutual funds		0		0
Total trading securities		0		0
Securities Available-for-Sale
Securities available-for-sale, at fair value		1,826,311		1,837,649
Mortgage servicing rights (MSRs)	[1]	0
Derivative assets	[1]	20,898		18,880
Liabilities:
Derivative liabilities	[2]	23,160		21,150
Recurring | Level 2 | U.S. treasury securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 2 | U.S. agency securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		175,058		183,637
Recurring | Level 2 | CMOs
Securities Available-for-Sale
Securities available-for-sale, at fair value		1,006,164		1,047,446
Recurring | Level 2 | MBSs
Securities Available-for-Sale
Securities available-for-sale, at fair value		373,660		332,655
Recurring | Level 2 | Municipal securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		264,402		270,846
Recurring | Level 2 | CDOs
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 2 | Equity securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		7,027		3,065
Recurring | Level 3
Trading securities:
Money market funds		0		0
Mutual funds		0		0
Total trading securities		0		0
Securities Available-for-Sale
Securities available-for-sale, at fair value		33,454		33,260
Mortgage servicing rights (MSRs)	[1]	5,925		6,120
Derivative assets	[1]	0		0
Liabilities:
Derivative liabilities	[2]	0		0
Recurring | Level 3 | U.S. treasury securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 3 | U.S. agency securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 3 | CMOs
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 3 | MBSs
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 3 | Municipal securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		0		0
Recurring | Level 3 | CDOs
Securities Available-for-Sale
Securities available-for-sale, at fair value		33,454		33,260
Recurring | Level 3 | Equity securities
Securities Available-for-Sale
Securities available-for-sale, at fair value		$ 0		$ 0
[1]	Included in other assets in the Consolidated Statements of Financial Condition.
[2]	Included in other liabilities in the Consolidated Statements of Financial Condition.

Fair Value (Details) - Unobserv

Fair Value (Details) - Unobservable Inputs Used In The Valuation of CDOs - CDOs	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Minimum
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
Probability of prepayment	0.00%	0.00%
Probability of default	15.60%	16.70%
Loss given default	93.30%	93.30%
Probability of deferral cure	0.00%	7.60%
Maximum
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
Probability of prepayment	10.90%	10.90%
Probability of default	44.10%	46.80%
Loss given default	99.20%	98.90%
Probability of deferral cure	100.00%	100.00%

Fair Value (Details) - Carrying

Fair Value (Details) - Carrying Value of Level 3 Securities Available-for-Sale - CDOs - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Rollforward of the Carrying Value of CDOs [Roll Forward]
Beginning balance		$ 33,436	$ 30,757	$ 33,260	$ 31,529
Change in other comprehensive income	[1]	6	(244)	135	(1,030)
Other		12	(82)	59	(68)
Ending balance		$ 33,454	$ 30,431	$ 33,454	$ 30,431
[1]	Included in unrealized holding gains in the Consolidated Statements of Comprehensive Income.

Fair Value (Details) - Narrativ

Fair Value (Details) - Narrative - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Total amount of loans being serviced for the benefit of others at the end of the period	$ 626.5	$ 640.5
Minimum
Fair Value (Details) [Line Items]
Appraisal adjustment (percent)	0.00%
Maximum
Fair Value (Details) [Line Items]
Appraisal adjustment (percent)	15.00%

Fair Value (Details) - Signific

Fair Value (Details) - Significant Unobservable Inputs Used In the Valuation of MSRs	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Minimum
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items]
Prepayment speed	8.80%	7.70%
Maturity (months)	8 months	12 months
Discount rate	9.50%	9.50%
Maximum
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items]
Prepayment speed	25.30%	22.80%
Maturity (months)	92 months	103 months
Discount rate	13.00%	13.00%

Fair Value (Details) - Carryi85

Fair Value (Details) - Carrying Value of Mortgage Servicing Rights - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance		$ 6,245	$ 5,022	$ 6,120	$ 1,853
Additions from acquisition		0	0	0	3,092
New MSRs		205	162	361	347
Total gains (losses) included in earnings:
Changes in valuation inputs and assumptions	[1]	(260)	(132)	(88)	(172)
Other changes in fair value	[2]	(265)	(114)	(468)	(182)
Ending balance		5,925	4,938	5,925	4,938
Contractual servicing fees earned	[1]	$ 384	$ 366	$ 779	$ 549
[1]	Included in mortgage banking income in the Condensed Consolidated Statements of Income and related to assets held as of June 30, 2017 and 2016.
[2]	Primarily represents changes in expected future cash flows due to payoffs and paydowns.

Fair Value (Details) - Assets M

Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
OREO		$ 26,493	$ 26,083
Level 1 | Nonrecurring
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
Collateral-dependent impaired loans	[1]	0	0
OREO	[2]	0	0
Loans held-for-sale	[3]	0	0
Assets held-for-sale	[4]	0	0
Level 2 | Nonrecurring
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
Collateral-dependent impaired loans	[1]	0	0
OREO	[2]	0	0
Loans held-for-sale	[3]	0	0
Assets held-for-sale	[4]	0	0
Level 3 | Nonrecurring
Fair Value (Details) - Assets Measured At Fair Value On A Non-Recurring Basis [Line Items]
Collateral-dependent impaired loans	[1]	40,698	22,019
OREO	[2]	6,835	8,624
Loans held-for-sale	[3]	16,922	10,484
Assets held-for-sale	[4]	$ 11,732	$ 4,075
[1]	Includes impaired loans with charge-offs and impaired loans with a specific reserve during the periods presented.
[2]	Includes OREO with fair value adjustments subsequent to initial transfer that occurred during the periods presented.
[3]	Included in other assets in the Consolidated Statements of Financial Condition.
[4]	Included in premises, furniture, and equipment in the Consolidated Statements of Financial Condition.

Fair Value (Details) - Financia

Fair Value (Details) - Financial Instruments - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets:
Cash and due from banks	$ 181,171	$ 155,055
Interest-bearing deposits in other banks	103,181	107,093
Securities held-to-maturity	17,353	22,291
FHLB and FRB stock	66,333	59,131
Loans	10,139,788	8,168,062
Investment in BOLI	278,353	219,746
Liabilities:
Deposits	10,999,720	8,828,603
Borrowed funds	639,333	879,008
Senior and subordinated debt	194,886	194,603
Level 1
Assets:
Cash and due from banks	181,171	155,055
Level 2
Assets:
Interest-bearing deposits in other banks	103,181	107,093
Securities held-to-maturity	14,899	18,212
FHLB and FRB stock	66,333	59,131
Liabilities:
Deposits	10,989,384	8,820,572
Borrowed funds	639,333	879,008
Senior and subordinated debt	205,757	197,888
Accrued interest payable	4,470	3,416
Level 3
Assets:
Loans	9,905,748	7,973,845
Investment in BOLI	278,353	219,746
Accrued interest receivable	39,766	34,384
Other interest-earning assets	454	834
Carrying Amount | Level 1
Assets:
Cash and due from banks	181,171	155,055
Carrying Amount | Level 2
Assets:
Interest-bearing deposits in other banks	103,181	107,093
Securities held-to-maturity	17,353	22,291
FHLB and FRB stock	66,333	59,131
Liabilities:
Deposits	10,999,720	8,828,603
Borrowed funds	639,333	879,008
Senior and subordinated debt	194,886	194,603
Accrued interest payable	4,470	3,416
Carrying Amount | Level 3
Assets:
Loans	10,143,706	8,172,584
Investment in BOLI	278,353	219,746
Accrued interest receivable	39,766	34,384
Other interest-earning assets	$ 454	$ 834