TCF Financial 10-Q 10 May 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	May 08, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	CHEMICAL FINANCIAL CORP
Entity Central Index Key	19,612
Document Type	10-Q
Document Period End Date	Mar. 31, 2017
Amendment Flag	false
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		71,121,541

Consolidated Statements of Fina

Consolidated Statements of Financial Position - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Cash and cash equivalents:
Cash and cash due from banks	$ 191,940	$ 237,758
Interest-bearing deposits with the Federal Reserve Bank and other banks	249,840	236,644
Total cash and cash equivalents	441,780	474,402
Investment securities:
Available-for-sale, at fair value	1,275,846	1,234,964
Held-to-maturity, at amortized cost (fair value of $639,800 and $608,531, respectively)	647,192	623,427
Total investment securities	1,923,038	1,858,391
Loans held-for-sale, at fair value	39,123	81,830
Loans	13,273,392	12,990,779
Allowance for loan losses	(78,774)	(78,268)
Net loans	13,194,618	12,912,511
Premises and equipment	142,763	145,012
Loan servicing rights ($64,604 and $48,085 measured at fair value, respectively)	64,604	58,315
Goodwill	1,133,534	1,133,534
Other intangible assets	38,848	40,211
Interest receivable and other assets	658,665	650,973
Total assets	17,636,973	17,355,179
Deposits:
Noninterest-bearing	3,399,287	3,341,520
Interest-bearing	9,733,060	9,531,602
Total deposits	13,132,347	12,873,122
Interest payable and other liabilities	114,789	134,637
Securities sold under agreements to repurchase with customers	398,910	343,047
Short-term borrowings	900,000	825,000
Long-term borrowings	490,876	597,847
Total liabilities	15,036,922	14,773,653
Shareholders’ equity
Preferred stock, no par value: Authorized – 2,000,000 shares at 3/31/2017 and 12/31/2016, none issued	0	0
Common stock, $1.00 par value per share, Authorized - 100,000,000 shares at 3/31/2017 and 12/31/2016, Issued and outstanding — 71,117,908 shares at 3/31/2017 and 70,599,133 shares at 12/31/2016	71,118	70,599
Additional paid-in capital	2,194,705	2,210,762
Retained earnings	372,193	340,201
Accumulated other comprehensive loss	(37,965)	(40,036)
Total shareholders’ equity	2,600,051	2,581,526
Total liabilities and shareholders’ equity	$ 17,636,973	$ 17,355,179

Consolidated Statements of Fin3

Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Held-to-maturity, fair value	$ 639,800	$ 608,531
Loan servicing rights, fair value	$ 64,604	$ 48,085
Preferred stock, no par value (in dollars per share)
Preferred stock, shares authorized (in shares)	2,000,000	2,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	71,117,908	70,599,133
Common stock, shares outstanding (in shares)	71,117,908	70,599,133

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Interest income
Interest and fees on loans	$ 132,485	$ 74,401
Interest on investment securities:
Taxable	4,756	1,929
Tax-exempt	4,235	2,665
Dividends on nonmarketable equity securities	621	256
Interest on deposits with the Federal Reserve Bank, other banks and Federal funds sold	799	213
Total interest income	142,896	79,464
Interest expense
Interest on deposits	8,916	4,059
Interest on short-term borrowings	1,658	100
Interest on long-term borrowings	2,225	975
Total interest expense	12,799	5,134
Net interest income	130,097	74,330
Provision for loan losses	4,050	1,500
Net interest income after provision for loan losses	126,047	72,830
Noninterest income
Service charges and fees on deposit accounts	8,004	5,720
Wealth management revenue	5,827	5,201
Other charges and fees for customer services	8,891	6,392
Mortgage banking revenue	9,160	1,405
Gain on sale of investment securities	90	19
Other	6,038	682
Total noninterest income	38,010	19,419
Operating expenses
Salaries, wages and employee benefits	60,248	33,890
Occupancy	7,392	4,905
Equipment and software	8,517	4,404
Merger and acquisition-related transaction expenses	4,167	2,594
Other	23,872	13,094
Total operating expenses	104,196	58,887
Income before income taxes	59,861	33,362
Income tax expense	12,257	9,757
Net income	$ 47,604	$ 23,605
Earnings per common share:
Basic (in dollars per share)	$ 0.67	$ 0.61
Diluted (in dollars per share)	0.67	0.60
Cash dividends declared per common share (in dollars per share)	$ 0.27	$ 0.26

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 47,604	$ 23,605
Other comprehensive income, net of tax:
Unrealized holding gains on securities available-for-sale arising during the period	2,739	4,199
Reclassification adjustment for gains on realized income	(90)	(19)
Tax effect	(927)	(1,463)
Net unrealized gains on securities available-for-sale, net of tax	1,722	2,717
Adjustment for pension and other postretirement benefits	537	(577)
Tax effect	(188)	202
Net adjustment for pension and other postretirement benefits	349	(375)
Other comprehensive income, net of tax	2,071	2,342
Total comprehensive income, net of tax	$ 49,675	$ 25,947

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands		Total	Stock options	Restricted stock units	Restricted stock awards	Common stock	Common stockStock options	Common stockRestricted stock units	Common stockRestricted stock awards	Additional paid-in capital	Additional paid-in capitalStock options	Additional paid-in capitalRestricted stock units	Additional paid-in capitalRestricted stock awards	Retained earnings	Accumulated other comprehensive income (loss)
Beginning balance at Dec. 31, 2015		$ 1,015,974				$ 38,168				$ 725,280				$ 281,558	$ (29,032)
Changes in Stockholders' Equity
Comprehensive income		25,947												23,605	2,342
Cash dividends declared and paid, $0.27 and $0.26 per share at March 31, 2017 and March 31, 2016, respectively		(9,961)												(9,961)
Shares issued under share-based compensation			$ 309	$ (727)			$ 36	$ 43			$ 273	$ (770)
Share-based compensation expense		749				1				748
Ending balance at Mar. 31, 2016		1,032,291				38,248				725,531				295,202	(26,690)
Changes in Stockholders' Equity
Cumulative effect adjustment of change in accounting policy, net of tax impact	[1]	3,659												3,659
Beginning balance at Dec. 31, 2016		2,581,526				70,599				2,210,762				340,201	(40,036)
Changes in Stockholders' Equity
Comprehensive income		49,675												47,604	2,071
Cash dividends declared and paid, $0.27 and $0.26 per share at March 31, 2017 and March 31, 2016, respectively		(19,271)												(19,271)
Shares issued under share-based compensation			$ (16,696)	$ (1,295)	$ (1,281)		$ 508	$ 35	$ (25)		$ (17,204)	$ (1,330)	$ (1,256)
Share-based compensation expense		3,734				1				3,733
Ending balance at Mar. 31, 2017		$ 2,600,051				$ 71,118				$ 2,194,705				$ 372,193	$ (37,965)
[1]	Refer to Footnote 1, Basis of Presentation and Accounting Policies and Footnote 8, Loan Servicing Rights, for further details on this change in accounting policy election.

Consolidated Statements of Cha7

Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Stockholders' Equity [Abstract]
Dividend declared (in dollars per share)	$ 0.27	$ 0.26

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities
Net income	$ 47,604	$ 23,605
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	4,050	1,500
Gain on sales of loans	(6,120)	(1,296)
Proceeds from sales of loans	191,531	45,928
Loans originated for sale	(142,704)	(43,972)
Net gains on sale of investment securities	(90)	(19)
Net gains from sales/writedowns of other real estate and repossessed assets	(700)	(547)
Depreciation of premises and equipment	4,521	2,775
Amortization of intangible assets	1,513	2,169
Additions to loan servicing rights	(1,753)	(331)
Valuation change in loan servicing rights	1,125	0
Net amortization of premiums and discounts on investment securities	4,129	1,493
Share-based compensation expense	3,734	749
Deferred income tax expense (benefit)	17,948	0
Net increase in interest receivable and other assets	(29,660)	(737)
Net decrease in interest payable and other liabilities	(19,282)	(11,875)
Net cash provided by operating activities	75,846	19,442
Investment securities – available-for-sale:
Proceeds from maturities, calls and principal reductions	60,885	42,281
Proceeds from sales and redemptions	0	644
Purchases	(102,702)	0
Investment securities – held-to-maturity:
Proceeds from maturities, calls and principal reductions	9,408	8,133
Purchases	(33,628)	(16,965)
Net increase in loans	(290,438)	(101,915)
Proceeds from sales of other real estate and repossessed assets	5,734	2,705
Purchases of premises and equipment, net of disposals	(2,272)	(2,406)
Net cash used in investing activities	(353,013)	(67,523)
Cash flows from financing activities
Net increase in interest- and noninterest-bearing demand deposits and savings accounts	350,763	234,102
Net decrease in time deposits	(91,538)	(40,753)
Net increase (decrease) in securities sold under agreements to repurchase with customers and other short-term borrowings	130,863	(113,816)
Proceeds from issuance of long-term borrowings	0	50,000
Repayment of long-term borrowings	(107,000)	(18,558)
Cash dividends paid	(19,271)	(9,961)
Proceeds from directors’ stock plans and exercise of stock options, net of shares withheld	1,578	382
Cash paid for payroll taxes upon conversion of share-based awards	(20,850)	(730)
Net cash provided by financing activities	244,545	100,666
Net increase (decrease) in cash and cash equivalents	(32,622)	52,585
Cash and cash equivalents at beginning of period	474,402	238,789
Cash and cash equivalents at end of period	441,780	291,374
Supplemental disclosures of cash flow information:
Interest paid	12,989	5,080
Income tax refunds, net of income taxes paid	(24,397)	0
Loans transferred to other real estate and repossessed assets	$ 4,281	$ 1,667

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Nature of Operations Chemical Financial Corporation ("Corporation" or "Chemical") operates in a single operating segment — commercial banking. The Corporation is a financial holding company, headquartered in Midland, Michigan, that operates through one commercial bank, Chemical Bank. Chemical Bank operates within Michigan, Ohio and Indiana as a state-chartered commercial bank. Chemical Bank operates through an internal organizational structure of seven regional banking units and offers a full range of traditional banking and fiduciary products and services to the residents and business customers in the bank’s geographical market areas. The products and services offered by the regional banking units, through branch banking offices, are generally consistent throughout the Corporation, as is the pricing of those products and services. The marketing of products and services throughout the Corporation’s regional banking units is generally uniform, as many of the markets served by the regional banking units overlap. The distribution of products and services is uniform throughout the Corporation’s regional banking units and is achieved primarily through retail branch banking offices, automated teller machines and electronically accessed banking products. The Corporation’s primary sources of revenue are interest from its loan products and investment securities, service charges and fees from customer deposit accounts, wealth management revenue and mortgage banking revenue. Basis of Presentation and Principles of Consolidation The accompanying unaudited consolidated financial statements of the Corporation and its subsidiaries have been prepared in accordance with United States ("U.S.") generally accepted accounting principles ("GAAP") for interim financial information and with instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, the interim consolidated financial statements do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Corporation’s consolidated financial statements and footnotes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2016. In the opinion of management, the accompanying unaudited interim consolidated financial statements contain all adjustments believed necessary to present fairly the financial condition and results of operations of the Corporation for the periods presented. Operating results for the three months ended March 31, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 . Use of Estimates Management makes estimates and assumptions that affect the amounts reported in the Consolidated Financial Statements and accompanying footnotes. Estimates that are particularly susceptible to significant change include the determination of the allowance for loan losses, expected cash flows from acquired loans, fair value amounts related to business combinations, income taxes, goodwill impairment and those assets that require fair value measurement. Actual results could differ from these estimates. Reclassifications Certain amounts appearing in the consolidated financial statements and notes thereto for prior periods have been reclassified to conform with the current presentation. The reclassification had no effect on net income or shareholders’ equity as previously reported. Loan Servicing Rights Effective January 1, 2017, the Corporation elected to account for all loan servicing rights ("LSRs") previously accounted for under the lower of cost or fair value method under the fair value method. The guidance in ASC Subtopic 860-50, "Transfers and Servicing-Servicing Assets and Liabilities" provides that an entity may make an irrevocable decision to subsequently measure a class of servicing assets and servicing liabilities at fair value at the beginning of any fiscal year. The guidance allows for the Corporation to apply this election prospectively to all new and existing servicing assets and servicing liabilities. Management believes this election will provide more comparable results to peers as many of those within our industry group account for loans servicing rights under the fair value method. The change in accounting policy in the first quarter of 2017 results in a cumulative adjustment to increase retained earnings in the amount of $3.7 million , net of taxes. Investments in Qualified Affordable Housing Projects, Federal Historic Projects and New Market Tax Credits The Corporation invests in qualified affordable housing projects, federal historic projects, and new market projects for the purpose of community reinvestment and obtaining tax credits. Return on the Corporation's investment in these projects comes in the form of the tax credits and tax losses that pass through to the Corporation. The carrying value of the investments are reflected in "Interest receivable and other assets" on the Consolidated Statements of Financial Position. The Corporation utilizes the proportional amortization method to account for investments in qualified affordable housing projects and the equity method to account for investments in other tax credit projects. Under the proportional amortization method, the Corporation amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits. The Corporation recognized additional income tax expense attributable to the amortization of investments in qualified affordable housing projects of $0.8 million and $0.6 million during the three months ended March 31, 2017 and 2016, respectively. The Corporation's remaining investment in qualified affordable housing projects accounted for under the proportional amortization method totaled $31.8 million at March 31, 2017 and $29.5 million at December 31, 2016 . Under the equity method, the Corporation's share of the earnings or losses are included in "Other operating expenses" on the Consolidated Statements of Income. The Corporation's remaining investment in new market projects accounted for under the equity method totaled $10.7 million and $10.9 million at March 31, 2017 and December 31, 2016 , respectively. The Corporation's unfunded equity contributions relating to investments in qualified affordable housing projects, federal historic tax projects and new market projects is recorded in "Interest payable and other liabilities" on the Consolidated Statements of Financial Position. The Corporation's remaining unfunded equity contributions totaled $18.5 million and $16.0 million at March 31, 2017 and December 31, 2016 , respectively. Management analyzes these investments for potential impairment when events or changes in circumstances indicate that it is more-likely-than-not that the carrying amount of the investment will not be realized. An impairment loss is measured as the amount by which the carrying amount of an investment exceeds its fair value. There were no impairment losses recognized as of March 31, 2017 or December 31, 2016 . The Corporation consolidates variable interest entities ("VIEs") in which it is the primary beneficiary. In general, a VIE is an entity that either (i) has an insufficient amount of equity to carry out its principal activities without additional subordinated financial support, (ii) has a group of equity owners that are unable to make significant decisions about its activities or (iii) has a group of equity owners that do not have the obligation to absorb losses or the right to receive returns as generated by its operations. If any of these characteristics are present, the entity is subject to a variable interests consolidation model, and consolidation is based on variable interests, not on ownership of the entity's outstanding voting stock. Variable interests are defined as contractual, ownership, or other monetary interests in an entity that change with fluctuations in the entity's net asset value. The primary beneficiary consolidates the VIE. The primary beneficiary is defined as the enterprise that has the power to direct the activities and absorb losses or the right to receive benefits. The Corporation is a significant limited partner in the qualified affo rdable housing, federal historic and new market projects it has invested in . These projects meet the definition of VIEs. However, the Corporation is not the primary beneficiary of any of the VIEs in which it holds a limited partnership interest; therefore, the VIEs are not consolidated in the Corporation's consolidated financial statements.

Mergers and Acquisitions

Mergers and Acquisitions	3 Months Ended
	Mar. 31, 2017
Business Combinations [Abstract]
Mergers and Acquisitions	Mergers and Acquisitions Merger with Talmer Bancorp, Inc. On August 31, 2016, the Corporation completed a merger with Talmer Bancorp, Inc. ("Talmer") for total consideration of $1.61 billion . As a result of the merger, the Corporation issued 32.1 million shares of its common stock based on an exchange ratio where each Talmer shareholder received 0.4725 shares of the Corporation's common stock, and $1.61 in cash, for each share of Talmer common stock. In conjunction with the merger, the Corporation entered into and drew on a $125.0 million credit facility. The proceeds from the credit facility were used to pay off the Corporation's $25.0 million line-of-credit and a $37.5 million line-of-credit of Talmer, with the remaining proceeds used to partially fund the cash portion of the merger consideration. The Corporation incurred $4.2 million and $2.6 million of merger and acquisition-related transaction expenses during the three months ended March 31, 2017 and 2016 , respectively, primarily related to the merger with Talmer. As a result of the merger, Talmer Bank and Trust became a wholly-owned subsidiary of the Corporation. Talmer Bank and Trust was consolidated with and into Chemical Bank during the fourth quarter of 2016. The Company determined that the merger with Talmer constitutes a business combination as defined by ASC 805. Accordingly, the assets acquired and liabilities assumed were recorded at their fair values on the date of acquisition. Fair values were determined in accordance with the guidance provided in ASC Topic 820, Fair Value Measurements. In many cases the determination of the fair values required management to make estimates about discount rates, future expected cash flows, market conditions and other future events that are highly subjective in nature and subject to change. The following allocation is based on the information that was available to make preliminary estimates of the fair value and may change as additional information becomes available and additional analyses are completed. While the Corporation believes that information provided a reasonable basis for estimating the fair values, it expects that it could obtain additional information and evidence during the measurement period that may result in changes to the estimated fair value amounts. This measurement period ends on the earlier of one year after the merger date or the date we receive the information about the facts and circumstances that existed at the merger date. Subsequent adjustments, if necessary, will be reflected in future filings. These refinements include: (1) changes in the estimated fair value of loans acquired: (2) changes in the estimated fair value of intangible assets acquired: (3) changes in deferred tax assets related to fair value estimates and a change in the expected realization of items considered to be net operating loss carry forwards and (4) a change in the goodwill caused by the net effect of these adjustments. (Dollars in thousands) Consideration paid: Stock $ 1,504,811 Cash 107,638 Total consideration 1,612,449 Fair value of identifiable assets acquired: Cash and cash equivalents 433,352 Investment securities: Available-for-sale 808,894 Held-to-maturity 1,657 Loans held-for-sale 244,916 Loans 4,882,402 Premises and equipment 38,793 Loan servicing rights 42,462 Other intangible assets 19,088 Interest receivable and other assets 395,119 Total identifiable assets acquired $ 6,866,683 Fair value of liabilities assumed: Noninterest-bearing deposits 1,236,902 Interest-bearing deposits 4,057,716 Interest payable and other liabilities 99,482 Securities sold under agreements to repurchase with customers 19,704 Short-term borrowings 387,500 Long-term borrowings 299,597 Total liabilities assumed $ 6,100,901 Fair value of net identifiable assets acquired $ 765,782 Goodwill resulting from acquisition $ 846,667 Information regarding loans accounted for under ASC 310-30 at the merger date is as follows: (Dollars in thousands) Accounted for under ASC 310-30: Contractual cash flows $ 5,968,488 Contractual cash flows not expected to be collected (nonaccretable difference) 223,959 Expected cash flows 5,744,529 Interest component of expected cash flows (accretable yield) 862,127 Fair value at acquisition $ 4,882,402 Unaudited Pro Forma Combined Results of Operations The following unaudited pro forma financial information presents the consolidated results of operation of the Corporation and Talmer as if the merger had occurred as of January 1, 2016. The unaudited pro forma combined results of operations are presented solely for information purposes and are not intended to represent or be indicative of the consolidated results of operations that Chemical would have reported had these transactions been completed as of the dates and for the periods presented, nor are they necessarily indicative of future results. In particular, no adjustments have been made to eliminate the amount of Talmer's provision for loan losses incurred prior to the acquisition date that would not have been necessary had the acquired loans been recorded at fair value as of the beginning of each period indicated. In accordance with Article 11 of SEC Regulation S-X, transaction costs directly attributable to the acquisitions have been excluded. For the three months ended, (Dollars in thousands) March 31, 2017 (1) March 31, 2016 Net interest and other income $ 168,107 $ 157,932 Net Income 47,604 39,028 Earnings per share: Basic $ 0.67 $ 0.56 Diluted 0.67 0.55 (1) As the business combination was effective August 31, 2016, there were no proforma adjustments for the three months ended March 31, 2017.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value, as defined by GAAP, is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. A fair value measurement assumes that the transaction to sell the asset or transfer the liability occurs in the principal market for the asset or liability or, in the absence of a principal market, the most advantageous market for the asset or liability. The price in the principal (or most advantageous) market used to measure the fair value of the asset or liability is not adjusted for transaction costs. An orderly transaction is a transaction that assumes exposure to the market for a period prior to the measurement date to allow for market activities that are usual and customary for transactions involving such assets and liabilities; it is not a forced transaction. Market participants are buyers and sellers in the principal market that are (i) independent, (ii) knowledgeable, (iii) able to transact and (iv) willing to transact. The Corporation utilizes fair value measurements to record fair value adjustments to certain assets and to determine fair value disclosures. Investment securities — available-for-sale, loans held-for-sale, loan servicing rights and derivatives are recorded at fair value on a recurring basis. Additionally, the Corporation may be required to record other assets, such as impaired loans, goodwill, other intangible assets, other real estate and repossessed assets, at fair value on a nonrecurring basis. These nonrecurring fair value adjustments typically involve the application of lower of cost or market accounting or write-downs of individual assets. The Corporation determines the fair value of its financial instruments based on a three-level hierarchy established by GAAP. The classification and disclosure of assets and liabilities within the hierarchy is based on whether the inputs to the valuation methodology used for measurement are observable or unobservable. Observable inputs reflect market-derived or market-based information obtained from independent sources, while unobservable inputs reflect management’s estimates about market data. The three levels of inputs that may be used to measure fair value within the GAAP hierarchy are as follows: Level 1 Valuation is based upon quoted prices for identical instruments traded in active markets. Level 1 valuations for the Corporation include U.S. Treasury securities that are traded by dealers or brokers in active over-the-counter markets. Valuations are obtained from a third-party pricing service for these investment securities. Level 2 Valuation is based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-based valuation techniques for which all significant assumptions are observable in the market. Level 2 valuations for the Corporation include government sponsored agency securities, including securities issued by the Federal Home Loan Bank, Federal Home Loan Mortgage Corporation, Federal National Mortgage Association, Federal Farm Credit Bank, Student Loan Marketing Corporation and the Small Business Administration, securities issued by certain state and political subdivisions, residential mortgage-backed securities, collateralized mortgage obligations, corporate bonds, preferred stock and available-for-sale trust preferred securities. Valuations are obtained from a third-party pricing service for these investment securities. Additionally included in Level 2 valuations are loans held for sale and derivative assets and liabilities. Level 3 Valuation is generated from model-based techniques that use at least one significant assumption not observable in the market. These unobservable assumptions reflect estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques include use of option pricing models, discounted cash flow models, yield curves and similar techniques. The determination of fair value requires management judgment or estimation and generally is corroborated by external data, which includes third-party pricing services. Level 3 valuations for the Corporation include securities issued by certain state and political subdivisions, held-to-maturity trust preferred investment securities, impaired loans, goodwill, core deposit intangible assets, non-compete intangible assets, LSRs and other real estate and repossessed assets. A description of the valuation methodologies used for instruments measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below. These valuation methodologies were applied to all of the Corporation’s financial assets and financial liabilities carried at fair value and all financial instruments disclosed at fair value. Transfers of asset or liabilities between levels of the fair value hierarchy are recognized at the beginning of the reporting period, when applicable. In general, fair value is based upon quoted market prices, where available. If quoted market prices are not available, fair value is based upon third-party pricing services when available. Fair value may also be based on internally developed models that primarily use, as inputs, observable market-based parameters. Valuation adjustments may be required to record financial instruments at fair value. Any such valuation adjustments are applied consistently over time. The Corporation's valuation methodologies may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. While management believes the Corporation’s valuation methodologies are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date. Furthermore, the fair value amounts may change significantly after the date of the statement of financial position from the amounts reported in the consolidated financial statements and related notes. Assets and Liabilities Recorded at Fair Value on a Recurring Basis Investment securities: Investment securities classified as available-for-sale are recorded at fair value on a recurring basis. Fair value measurement is based upon quoted prices, if available. If quoted prices are not available, fair values are generally measured using independent pricing models or other model-based valuation techniques that include market inputs, such as benchmark yields, reported trades, broker dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, reference data and industry and economic events. Loans held-for-sale: The Corporation has elected the fair value option for all residential mortgage loans held-for-sale. Accordingly, loans held-for-sale are recorded at fair value on a recurring basis. The fair values of loans held-for-sale are based on the market price for similar loans sold in the secondary market, and therefore, are classified as Level 2 valuations. Loan servicing rights: Effective January 1, 2017, the Corporation elected to account for all LSRs under the fair value measurement method. LSRs acquired related to the merger with Talmer effective August 31, 2016 were also previously accounted for under the fair value measurement method based on accounting election. A third party valuation model is used to determine the fair value at the end of each reporting period utilizing a discounted cash flow analysis using interest rates and prepayment speed assumptions currently quoted for comparable instruments and a discount rate determined by management. Because of the nature of the valuation inputs, the Corporation classifies loan servicing rights as Level 3. Refer to Note 8, “Loan Servicing Rights,” for the assumptions included in the valuation of loan servicing rights. Derivatives: The Corporation enters into interest rate lock commitments with prospective borrowers to be sold into the secondary market and forward commitments for the future delivery of mortgage loans to third party investors, which are carried at fair value on a recurring basis. The fair value of these commitments is based on the fair value of related mortgage loans determined using observable market data. Interest rate lock commitments are adjusted for expectations of exercise and funding. This adjustment is not considered to be a material input. The Corporation classifies interest rate lock commitments and forward contracts related to mortgage loans to be delivered for sale as recurring Level 2. Derivative instruments held or issued for customer-initiated activities are traded in over-the counter markets where quoted market prices are not readily available. Fair value for over-the-counter derivative instruments is measured on a recurring basis using third party models that use primarily market observable inputs, such as yield curves and option volatilities. The fair value for these derivatives may include a credit valuation adjustment that is determined by applying a credit spread for the counterparty or the Corporation, as appropriate, to the total expected exposure of the derivative after considering collateral and other master netting arrangements. These adjustments, which are considered Level 3 inputs, are based on estimates of current credit spreads to evaluate the likelihood of default. The Corporation assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions at both March 31, 2017 and December 31, 2016 and it was determined that the credit valuation adjustments were not significant to the overall valuation of its derivatives. As a result, the Corporation classifies its customer-initiated derivatives valuations in Level 2 of the fair value hierarchy. Written and purchased option derivatives consist of instruments to facilitate an equity-linked time deposit product (the "Power Equity CD"). The Power Equity CD is a time deposit that provides the purchaser a guaranteed return of principal at maturity plus a potential equity return, while the Corporation receives a known stream of funds based on equity returns. The written and purchased options are mirror derivative instruments which are carried at fair value on the Consolidated Statements of Financial Position. Fair value measurements for the Power Equity CD are determined using quoted prices of underlying stocks, along with other terms and features of the derivative instrument. As a result, the Power Equity CD derivatives are classified as Level 2 valuations. Disclosure of Recurring Basis Fair Value Measurements For assets and liabilities measured at fair value on a recurring basis, quantitative disclosures about the fair value measurements for each major category of assets and liabilities follow: (Dollars in thousands) Quoted Prices In Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total March 31, 2017 Investment securities – available-for-sale: U.S. Treasury securities $ 5,793 $ — $ — $ 5,793 Government sponsored agencies — 224,339 — 224,339 State and political subdivisions — 300,409 — 300,409 Residential mortgage-backed securities — 256,544 — 256,544 Collateralized mortgage obligations — 367,321 — 367,321 Corporate bonds — 89,253 — 89,253 Preferred stock and trust preferred securities — 32,187 — 32,187 Total investment securities – available-for-sale 5,793 1,270,053 — 1,275,846 Loans held-for-sale — 39,123 — 39,123 Loan servicing rights — — 64,604 64,604 Derivative assets: Customer-initiated derivatives — 6,377 — 6,377 Interest rate lock commitments — 2,178 — 2,178 Power Equity CD — 2,234 — 2,234 Total derivatives — 10,789 — 10,789 Total assets at fair value $ 5,793 $ 1,319,965 $ 64,604 $ 1,390,362 Derivative liabilities: Customer-initiated derivatives — 6,342 — 6,342 Forward contracts related to mortgage loans to be delivered for sale — 342 — 342 Power Equity CD — 2,234 — 2,234 Total derivatives — 8,918 — 8,918 Total liabilities at fair value $ — $ 8,918 $ — $ 8,918 December 31, 2016 Investment securities – available-for-sale: U.S. Treasury securities $ 5,793 $ — $ — $ 5,793 Government sponsored agencies — 215,011 — 215,011 State and political subdivisions — 300,088 — 300,088 Residential mortgage-backed securities — 272,282 — 272,282 Collateralized mortgage obligations — 320,025 — 320,025 Corporate bonds — 89,474 — 89,474 Preferred stock and trust preferred securities — 32,291 — 32,291 Total investment securities – available-for-sale 5,793 1,229,171 — 1,234,964 Loans held-for-sale — 81,830 — 81,830 Loan servicing rights — — 48,085 48,085 Derivative assets: Customer-initiated derivatives — 4,406 — 4,406 Forward contracts related to mortgage loans to be delivered for sale — 635 — 635 Interest rate lock commitments — 956 — 956 Power Equity CD — 2,218 — 2,218 Total derivatives — 8,215 — 8,215 Total assets at fair value $ 5,793 $ 1,319,216 $ 48,085 $ 1,373,094 Derivative liabilities: Customer-initiated derivatives — 4,141 — 4,141 Power Equity CD — 2,218 — 2,218 Total derivatives — 6,359 — 6,359 Total liabilities at fair value $ — $ 6,359 $ — $ 6,359 There were no transfers between levels within the fair value hierarchy during the three months ended March 31, 2017. The following table summarizes the changes in Level 3 assets measured at fair value on a recurring basis. Three months ended March 31, 2017 (Dollars in thousands) Loan servicing rights Balance, beginning of period $ 48,085 Transfer in based on new accounting policy election (1) 15,891 Gains (losses): Recorded in earnings (realized): Recorded in “Mortgage banking revenue” (1,125 ) New originations 1,753 Balance, end of period $ 64,604 (1) Refer to Note 1 for further details. The Corporation has elected the fair value option for loans held-for-sale. These loans are intended for sale and the Corporation believes that the fair value is the best indicator of the resolution of these loans. Interest income is recorded based on the contractual terms of the loans in accordance with the Corporation's policy on loans held for investment in “Interest and fees on loans” in the Consolidated Statements of Income. There were no loans held-for-sale on nonaccrual status or 90 days past due and on accrual status as of March 31, 2017 and December 31, 2016 . The aggregate fair value, contractual balance (including accrued interest), and gain or loss for loans held-for-sale carried at fair value was as follows: (Dollars in thousands) March 31, 2017 December 31, 2016 Aggregate fair value $ 39,123 $ 81,830 Contractual balance 37,701 81,009 Unrealized gain (loss) 1,422 821 The total amount of gains (losses) from loans held-for-sale included in the Consolidated Statements of Income were as follows: For the three months ended (Dollars in thousands) 2017 2016 Interest income (1) $ 551 $ 19 Change in fair value (2) 601 — Total included in earnings $ 1,152 $ 19 (1) Included in "Interest and fees on loans" in the Consolidated Statements of Income. (2) Included in "Mortgage banking revenue" in the Consolidated Statements of Income. Assets and Liabilities Recorded at Fair Value on a Nonrecurring Basis Loans: The Corporation does not record loans held for investment at fair value on a recurring basis. However, from time to time, a loan is considered impaired and an allocation of the allowance (valuation allowance) may be established or a portion of the loan is charged off. Loans for which it is probable that payment of interest and principal will not be made in accordance with the contractual terms of the loan agreement are considered impaired. The fair value of impaired loans is estimated using one of several methods, including the loan’s observable market price, the fair value of the collateral or the present value of the expected future cash flows discounted at the loan’s effective interest rate. Those impaired loans not requiring a valuation allowance represent loans for which the fair value of the expected repayments or collateral exceed the remaining carrying amount of such loans. Impaired loans where a valuation allowance is established or a portion of the loan is charged off based on the fair value of collateral are subject to nonrecurring fair value measurement and require classification in the fair value hierarchy. The Corporation records impaired loans as Level 3 valuations as there is generally no observable market price or management determines the fair value of the collateral is further impaired below the independent appraised value. When management determines the fair value of the collateral is further impaired below appraised value, discounts ranging between 10% and 25% of the appraised value are used depending on the nature of the collateral and the age of the most recent appraisal. Goodwill: Goodwill is subject to impairment testing on an annual basis. The assessment of goodwill for impairment requires a significant degree of judgment. In the event the assessment indicates that it is more-likely-than-not that the fair value is less than the carrying value, the asset is considered impaired and recorded at fair value. Goodwill that is impaired and subject to nonrecurring fair value measurements is a Level 3 valuation. At March 31, 2017 and December 31, 2016 , no goodwill was impaired. Other intangible assets: Other intangible assets consist of core deposit intangible assets and non-compete intangible assets. These items are recorded at fair value when initially recorded. Subsequently, core deposit intangible assets and non-compete intangible assets are amortized primarily on an accelerated basis over periods ranging from ten to fifteen years and are subject to impairment testing whenever events or changes in circumstances indicate that the carrying amount exceeds the fair value of the asset. If core deposit intangible asset or non-compete intangible asset impairment is identified, the Corporation classifies impaired core deposit intangible assets and impaired non-compete intangible assets subject to nonrecurring fair value measurements as Level 3 valuations. At March 31, 2017 and December 31, 2016 , there was no impairment identified for core deposit intangible assets or non-compete intangible assets. Loan servicing rights: Prior to January 1, 2017, LSRs originated by the Corporation and those acquired in acquisitions of other institutions prior to the merger with Talmer were accounted for under the amortization method. The fair value of these LSRs were initially estimated using a model that calculates the net present value of estimated future cash flows using various assumptions, including prepayment speeds, the discount rate and servicing costs. If the valuation model reflected a value less than the carrying value, LSRs were adjusted to fair value, as determined by the model, through a valuation allowance. The Corporation classified the LSRs subject to nonrecurring fair value measurements as Level 3 valuations. At December 31, 2016 , the Corporation recognized a valuation allowance of $8 thousand related to impairment within certain pools attributable to the Corporation's servicing portfolios. As a result, the LSRs related to these servicing portfolios were considered to be recorded at fair value on a nonrecurring basis as of December 31, 2016 . Other real estate owned and repossessed assets : The carrying amounts for other real estate and repossessed assets are reported in the Consolidated Statements of Financial Position under “Interest receivable and other assets.” Other real estate and repossessed assets include real estate and other types of assets repossessed by the Corporation. Other real estate and repossessed assets are recorded at the lower of cost or fair value upon the transfer of a loan to other real estate and repossessed assets and, subsequently, continue to be measured and carried at the lower of cost or fair value. Fair value is based upon independent market prices, appraised values of the property or management’s estimation of the value of the property. The Corporation records other real estate and repossessed assets as Level 3 valuations as management generally determines that the fair value of the property is impaired below the appraised value. When management determines the fair value of the property is further impaired below appraised value, discounts ranging between 10% and 25% of the appraised value are used depending on the nature of the property and the age of the most recent appraisal. Disclosure of Nonrecurring Basis Fair Value Measurements For assets measured at fair value on a nonrecurring basis, quantitative disclosures about fair value measurements for each major category of assets follows: (Dollars in thousands) Quoted Prices In Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total March 31, 2017 Impaired originated loans $ — $ — $ 63,180 $ 63,180 Other real estate/repossessed assets — — 2,240 2,240 Total $ — $ — $ 65,420 $ 65,420 December 31, 2016 Impaired originated loans $ — $ — $ 62,184 $ 62,184 Other real estate/repossessed assets — — 1,386 1,386 Loan servicing rights — — 2 2 Total $ — $ — $ 63,572 $ 63,572 There were no liabilities recorded at fair value on a nonrecurring basis at March 31, 2017 and December 31, 2016 . The following table presents additional information about the significant unobservable inputs used in the fair value measurement of financial assets measured on a nonrecurring basis that were categorized within the Level 3 of the fair value hierarchy: (Dollars in thousands) Fair Value at March 31, 2017 Valuation Technique Significant Unobservable Inputs Range Impaired originated loans $ 63,180 Appraisal of collateral Discount for type of collateral and age of appraisal 10%-25% Other real estate/repossessed assets 2,240 Appraisal of property Discount for type of property and age of appraisal 10%-25% Disclosures about Fair Value of Financial Instruments GAAP requires disclosures about the estimated fair value of the Corporation's financial instruments, including those financial assets and liabilities that are not measured and reported at fair value on a recurring or nonrecurring basis. However, the method of estimating fair value for certain financial instruments, such as loans, that are not required to be measured on a recurring or nonrecurring basis, as prescribed by FASB ASC Topic 820, "Fair Value Measurement", does not incorporate the exit-price concept of fair value. The Corporation utilized the fair value hierarchy in computing the fair values of its financial instruments. In cases where quoted market prices were not available, the Corporation employed present value methods using unobservable inputs requiring management's judgment to estimate the fair values of its financial instruments, which are considered Level 3 valuations. These Level 3 valuations are affected by the assumptions made and, accordingly, do not necessarily indicate amounts that could be realized in a current market exchange. It is also the Corporation's general practice and intent to hold the majority of its financial instruments until maturity and, therefore, the Corporation does not expect to realize the estimated amounts disclosed. The methodologies for estimating the fair value of financial assets and financial liabilities on a recurring or nonrecurring basis are discussed above. At March 31, 2017 and December 31, 2016 , the estimated fair values of cash and cash equivalents, interest receivable and interest payable approximated their carrying values at those dates. The methodologies for other financial assets and financial liabilities follow. Investment securities — held-to-maturity : Fair value measurements for investment securities — held-to-maturity fair values are measured using independent pricing models or other model-based valuation techniques that include market inputs such as benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, reference data and industry and economic events. Fair value measurements using Level 2 valuations of investment securities — held-to-maturity includes investment securities issued by state and political subdivisions. Level 3 valuations include trust preferred investment securities. Nonmarketable equity securities: Fair value measurements of nonmarketable equity securities, which consist of Federal Home Loan Bank (FHLB) and Federal Reserve Bank (FRB) stock, are based on their redeemable value, which is cost. The market for these securities is restricted to the issuer of the stock and subject to impairment evaluation. It is not practicable to determine the fair value of these securities within the fair value hierarchy due to the restrictions placed on their transferability. Loans: The fair values of loans that are not considered impaired are estimated using a discounted cash flow model. The cash flows take into consideration current portfolio interest rates and repricing characteristics as well as assumptions relating to prepayment speeds. The discount rates take into consideration the current market interest rate environment, a credit risk component based on the credit characteristics of each loan portfolio, and a liquidity premium reflecting the liquidity or illiquidity of the market. The fair value measurements for loans are Level 3 valuations. Deposits: The fair values of deposit accounts without defined maturities, such as interest- and noninterest-bearing checking, savings and money market accounts, are estimated to be the amounts payable on demand. The fair values for variable-interest rate time deposits with defined maturities approximate their carrying amounts. Fair value measurements for fixed-interest rate time deposits with defined maturities are based on the discounted value of contractual cash flows, using the Corporation’s interest rates currently being offered for deposits of similar maturities, and are therefore classified as Level 2 valuations. However, if the estimated fair value is less than the carrying value, the carrying value is reported as the fair value. Securities sold under agreements to repurchase: Fair value measurements are based on the present value of future estimated cash flows using current interest rates offered to the Corporation under similar terms and are Level 2 valuations. Short-term borrowings: Short-term borrowings consist of short-term FHLB advances. Fair value measurements for short-term borrowings are based on the present value of future estimated cash flows using current interest rates offered to the Corporation for debt with similar terms and are Level 2 valuations. Lon g -term borrowings: Long-term borrowings consist of long-term FHLB advances, securities sold under agreements to repurchase with an unaffiliated financial institution, a term line-of-credit and subordinated debt obligations. Fair value measurements for long-term borrowings are based on the present value of future estimated cash flows using current interest rates offered to the Corporation for debt with similar terms and are therefore classified as Level 2 valuations. Financial guarantees : The Corporation’s unused commitments to extend credit, standby letters of credit and loan commitments have no carrying amount and have been estimated to have no realizable fair value. Historically, a majority of the unused commitments to extend credit have not been drawn upon and, generally, the Corporation does not receive fees in connection with these commitments other than standby letter of credit fees, which are not significant. A summary of carrying amounts and estimated fair values of the Corporation’s financial instruments not recorded at fair value in their entirety on a recurring basis on the Consolidated Statements of Financial Position was as follows: Level in Fair Value Measurement Hierarchy March 31, 2017 December 31, 2016 (Dollars in thousands) Carrying Amount Fair Value Carrying Amount Fair Value Financial assets: Cash and cash equivalents Level 1 $ 441,780 $ 441,780 $ 474,402 $ 474,402 Investment securities: Held-to-maturity Level 2 646,692 639,450 622,927 608,221 Held-to-maturity Level 3 500 350 500 310 Nonmarketable equity securities Level 2 129,939 129,939 97,350 97,350 Net loans (1) Level 3 13,194,618 13,347,793 12,912,511 13,069,315 Interest receivable Level 2 45,863 45,863 42,235 42,235 Financial liabilities: Deposits: Deposits without defined maturities Level 2 $ 10,213,518 $ 10,213,518 $ 9,862,755 $ 9,862,755 Time deposits Level 2 2,918,829 2,919,153 3,010,367 3,010,048 Total deposits 13,132,347 13,132,671 12,873,122 12,872,803 Interest payable Level 2 5,225 5,225 5,415 5,415 Securities sold under agreements to repurchase with customers Level 2 398,910 398,910 343,047 343,047 Short-term borrowings Level 2 900,000 899,777 825,000 825,000 Long-term borrowings Level 2 490,876 486,161 597,847 591,227 (1) Included $63.2 million and $62.2 million of impaired loans recorded at fair value on a nonrecurring basis at March 31, 2017 and December 31, 2016 , respectively.

Investment Securities

Investment Securities	3 Months Ended
	Mar. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities The following is a summary of the amortized cost and fair value of investment securities available-for-sale and investment securities held-to-maturity at March 31, 2017 and December 31, 2016 : Investment Securities Available-for-Sale (Dollars in thousands) Amortized Cost Unrealized Gains Unrealized Losses Fair Value March 31, 2017 U.S. Treasury securities $ 5,792 $ 1 $ — $ 5,793 Government sponsored agencies 225,993 153 1,807 224,339 State and political subdivisions 309,518 140 9,249 300,409 Residential mortgage-backed securities 260,703 45 4,204 256,544 Collateralized mortgage obligations 371,084 75 3,838 367,321 Corporate bonds 90,438 27 1,212 89,253 Preferred stock and trust preferred securities 31,426 1,042 281 32,187 Total $ 1,294,954 $ 1,483 $ 20,591 $ 1,275,846 December 31, 2016 U.S. Treasury securities $ 5,788 $ 5 $ — $ 5,793 Government sponsored agencies 216,890 189 2,068 215,011 State and political subdivisions 311,704 163 11,779 300,088 Residential mortgage-backed securities 276,162 112 3,992 272,282 Collateralized mortgage obligations 323,965 63 4,003 320,025 Corporate bonds 90,859 16 1,401 89,474 Preferred stock and trust preferred securities 31,353 1,018 80 32,291 Total $ 1,256,721 $ 1,566 $ 23,323 $ 1,234,964 Investment Securities Held-to-Maturity (Dollars in thousands) Amortized Cost Unrealized Gains Unrealized Losses Fair Value March 31, 2017 State and political subdivisions $ 646,692 $ 3,830 $ 11,072 $ 639,450 Trust preferred securities 500 — 150 350 Total $ 647,192 $ 3,830 $ 11,222 $ 639,800 December 31, 2016 State and political subdivisions $ 622,927 $ 2,648 $ 17,354 $ 608,221 Trust preferred securities 500 — 190 310 Total $ 623,427 $ 2,648 $ 17,544 $ 608,531 The majority of the Corporation’s residential mortgage-backed securities and collateralized mortgage obligations are backed by a U.S. government agency (Government National Mortgage Association) or a government sponsored enterprise (Federal Home Loan Mortgage Corporation or Federal National Mortgage Association). Proceeds from sales of securities and the associated gains and losses recorded in earnings are listed below: For the three months ended March 31, (Dollars in thousands) 2017 2016 Proceeds $ — $ 644 Gross gains 90 19 The following is a summary of the amortized cost and fair value of investment securities at March 31, 2017 , by maturity, for both available-for-sale and held-to-maturity investment securities. The maturities of residential mortgage-backed securities and collateralized mortgage obligations are based on scheduled principal payments. The maturities of all other debt securities are based on final contractual maturity. March 31, 2017 (Dollars in thousands) Amortized Cost Fair Value Investment Securities Available-for-Sale: Due in one year or less $ 248,015 $ 246,683 Due after one year through five years 529,893 524,707 Due after five years through ten years 347,825 340,248 Due after ten years 167,832 162,405 Preferred stock 1,389 1,803 Total $ 1,294,954 $ 1,275,846 Investment Securities Held-to-Maturity: Due in one year or less $ 70,242 $ 70,210 Due after one year through five years 271,055 268,753 Due after five years through ten years 146,712 144,004 Due after ten years 159,183 156,833 Total $ 647,192 $ 639,800 Securities with a carrying value of $911.9 million and $794.0 million were pledged at March 31, 2017 and December 31, 2016 , respectively, to secure borrowings and deposits. At March 31, 2017 and December 31, 2016 , there were no holdings of securities of any one issuer, other than the U.S. government and its agencies, in an amount greater than 10% of shareholders' equity. The following schedule summarizes information for both available-for-sale and held-to-maturity investment securities with gross unrealized losses at March 31, 2017 and December 31, 2016 , aggregated by category and length of time that individual securities have been in a continuous unrealized loss position. As of March 31, 2017 , the Corporation’s securities portfolio consisted of 2,309 securities, 1,418 of which were in an unrealized loss position. Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses March 31, 2017 Government sponsored agencies $ 108,300 $ 1,445 $ 11,203 $ 362 $ 119,503 $ 1,807 State and political subdivisions 705,870 19,603 26,084 718 731,954 20,321 Residential mortgage-backed securities 248,111 4,204 — — 248,111 4,204 Collateralized mortgage obligations 311,566 3,626 12,528 212 324,094 3,838 Corporate bonds 78,815 1,211 1,499 1 80,314 1,212 Trust preferred securities 10,511 281 350 150 10,861 431 Total $ 1,463,173 $ 30,370 $ 51,664 $ 1,443 $ 1,514,837 $ 31,813 December 31, 2016 Government sponsored agencies $ 105,702 $ 1,707 $ 15,023 $ 361 $ 120,725 $ 2,068 State and political subdivisions 758,063 28,158 26,810 975 784,873 29,133 Residential mortgage-backed securities 244,239 3,992 — — 244,239 3,992 Collateralized mortgage obligations 279,001 3,778 14,754 225 293,755 4,003 Corporate bonds 80,536 1,401 — — 80,536 1,401 Trust preferred securities 10,699 80 310 190 11,009 270 Total $ 1,478,240 $ 39,116 $ 56,897 $ 1,751 $ 1,535,137 $ 40,867 An assessment is performed quarterly by the Corporation to determine whether unrealized losses in its investment securities portfolio are temporary or other-than-temporary by carefully considering all reasonably available information. The Corporation reviews factors such as financial statements, credit ratings, news releases and other pertinent information of the underlying issuer or company to make its determination. Management did not believe any individual unrealized loss on any investment security, as of March 31, 2017 , represented other-than-temporary impairment (OTTI) as the unrealized losses for these securities resulted primarily from changes in benchmark U.S. Treasury interest rates and not credit issues. Management believed that the unrealized losses on investment securities at March 31, 2017 were temporary in nature and due primarily to changes in interest rates and reduced market liquidity and not as a result of credit-related issues. At March 31, 2017 , the Corporation did not have the intent to sell any of its impaired investment securities and believed that it was more-likely-than-not that the Corporation will not have to sell any such investment securities before a full recovery of amortized cost. Accordingly, at March 31, 2017 , the Corporation believed the impairments in its investment securities portfolio were temporary in nature. However, there is no assurance that OTTI may not occur in the future.

Loans

Loans	3 Months Ended
	Mar. 31, 2017
Receivables [Abstract]
Loans	Loans Loan portfolio segments are defined as the level at which an entity develops and documents a systematic methodology to determine its allowance. The Corporation has two loan portfolio segments (commercial loans and consumer loans) that it uses in determining the allowance. Both quantitative and qualitative factors are used by management at the loan portfolio segment level in determining the adequacy of the allowance for the Corporation. Classes of loans are a disaggregation of an entity’s loan portfolio segments. Classes of loans are defined as a group of loans which share similar initial measurement attributes, risk characteristics, and methods for monitoring and assessing credit risk. The Corporation has six classes of loans, which are set forth below. Commercial — Loans and lines of credit to varying types of businesses, including municipalities, school districts and nonprofit organizations, for the purpose of supporting working capital, operational needs and term financing of equipment. Repayment of such loans is generally provided through operating cash flows of the business. Commercial loans are predominately secured by equipment, inventory, accounts receivable, personal guarantees of the owner and other sources of repayment, although the Corporation may also secure commercial loans with real estate. Commercial real estate — Loans secured by real estate occupied by the borrower for ongoing operations, non-owner occupied real estate leased to one or more tenants and vacant land that has been acquired for investment or future land development. Real estate construction and land development — Real estate construction loans represent secured loans for the construction of business properties. Real estate construction loans often convert to a commercial real estate loan at the completion of the construction period. Land development loans represent secured development loans made to borrowers for the purpose of infrastructure improvements to vacant land to create finished marketable residential and commercial lots/land. Most land development loans are originated with the intention that the loans will be paid through the sale of developed lots/land by the developers within twelve months of the completion date. Land development loans at March 31, 2017 and December 31, 2016 were primarily comprised of loans to develop residential properties. Residential mortgage — Loans secured by one - to four -family residential properties, generally with fixed interest rates for periods of fifteen years or less. The loan-to-value ratio at the time of origination is generally 80% or less. Residential mortgage loans with a loan-to-value ratio of more than 80% generally require private mortgage insurance. Consumer installment — Loans to consumers primarily for the purpose of acquiring automobiles, recreational vehicles and personal watercraft and comprised primarily of indirect loans purchased from dealers. These loans consist of relatively small amounts that are spread across many individual borrowers. Home equity — Loans and lines of credit whereby consumers utilize equity in their personal residence, generally through a second mortgage, as collateral to secure the loan. Commercial, commercial real estate, and real estate construction and land development loans are referred to as the Corporation’s commercial loan portfolio, while residential mortgage, consumer installment and home equity loans are referred to as the Corporation’s consumer loan portfolio. A summary of the Corporation's loans follows: (Dollars in thousands) Originated Acquired (1) Total Loans March 31, 2017 Commercial loan portfolio: Commercial $ 1,989,609 $ 1,263,999 $ 3,253,608 Commercial real estate 2,114,540 1,983,231 4,097,771 Real estate construction and land development 327,740 126,071 453,811 Subtotal 4,431,889 3,373,301 7,805,190 Consumer loan portfolio: Residential mortgage 1,594,376 1,539,089 3,133,465 Consumer installment 1,342,063 138,994 1,481,057 Home equity 591,441 262,239 853,680 Subtotal 3,527,880 1,940,322 5,468,202 Total loans $ 7,959,769 $ 5,313,623 $ 13,273,392 (2 ) December 31, 2016 Commercial loan portfolio: Commercial $ 1,901,526 $ 1,315,774 $ 3,217,300 Commercial real estate 1,921,799 2,051,341 3,973,140 Real estate construction and land development 281,724 122,048 403,772 Subtotal 4,105,049 3,489,163 7,594,212 Consumer loan portfolio: Residential mortgage 1,475,342 1,611,132 3,086,474 Consumer installment 1,282,588 151,296 1,433,884 Home equity 595,422 280,787 876,209 Subtotal 3,353,352 2,043,215 5,396,567 Total loans $ 7,458,401 $ 5,532,378 $ 12,990,779 (2 ) (1) Acquired loans are accounted for under ASC 310-30. (2) Reported net of deferred costs totaling $15.0 million and $14.8 million at March 31, 2017 and December 31, 2016 , respectively. The Corporation acquired loans at fair value as of the acquisition date, which includes loan acquired in the acquisitions of Talmer, Lake Michigan Financial Corporation ("Lake Michigan"), Monarch Community Bancorp, Inc. ("Monarch"), Northwestern Bancorp, Inc. ("Northwestern") and O.A.K. Financial Corporation ("OAK"). Acquired loans are accounted for under ASC 310-30 which recognizes the expected shortfall of expected future cash flows, as compared to the contractual amount due, as nonaccretable discount. Any excess of the net present value of expected future cash flows over the acquisition date fair value is recognized as the accretable discount, or accretable yield. The accretable discount is recognized over the expected remaining life of the acquired loans on a pool basis. Activity for the accretable yield, which includes contractually due interest for acquired loans that have been renewed or extended since the date of acquisition and continue to be accounted for in loan pools in accordance with ASC 310-30, follows: (Dollars in thousands) Talmer Lake Michigan Monarch North-western OAK Total Three Months Ended March 31, 2017 Balance at beginning of period $ 798,210 $ 121,416 $ 27,182 $ 69,847 $ 23,316 $ 1,039,971 Additions (reductions) (1) — (939 ) 54 (1,058 ) 1,428 (515 ) Accretion recognized in interest income (44,571 ) (7,266 ) (1,181 ) (3,892 ) (3,277 ) (60,187 ) Reclassification from nonaccretable difference 21,139 — — — — 21,139 Balance at end of period $ 774,778 $ 113,211 $ 26,055 $ 64,897 $ 21,467 $ 1,000,408 Three Months Ended March 31, 2016 Balance at beginning of period $ — $ 152,999 $ 34,558 $ 82,623 $ 28,077 $ 298,257 Additions (reductions) (1) — (6,071 ) 128 (2,254 ) 1,516 (6,681 ) Accretion recognized in interest income — (8,953 ) (1,451 ) (4,001 ) (2,557 ) (16,962 ) Balance at end of period $ — $ 137,975 $ 33,235 $ 76,368 $ 27,036 $ 274,614 (1) Represents additions of estimated contractual interest expected to be collected from acquired loans being renewed or extended, less reductions in contractual interest resulting from the early payoff of acquired loans. As part of its ongoing assessment of the acquired loan portfolios, management has determined that the overall credit quality of the Talmer acquired loan portfolios has improved, which has resulted in an improvement in expected cash flows of certain loan pools in these acquired loan portfolios. Accordingly, management reclassified $21.1 million during the three months ended March 31, 2017 from the nonaccretable difference to the accretable yield for each of these acquired loan portfolios, which will increase amounts recognized into interest income over the estimated remaining lives of the loan pools within these portfolios. Credit Quality Monitoring The Corporation maintains loan policies and credit underwriting standards as part of the process of managing credit risk. These standards include making loans generally only within the Corporation’s market areas. The Corporation’s lending markets generally consist of communities throughout Michigan and additional communities located within Northeast Ohio and Northern Indiana. The Corporation, through Chemical Bank, has a commercial loan portfolio approval process involving underwriting and individual and group loan approval authorities to consider credit quality and loss exposure at loan origination. The loans in the Corporation’s commercial loan portfolio are risk rated at origination based on the grading system set forth below. The approval authority of relationship managers is established based on experience levels, with credit decisions greater than $2.0 million requiring group loan authority approval, except for six executive and senior officers who have varying loan limits exceeding $2.0 million and up to $3.5 million . With respect to the group loan authorities, Chemical Bank has various regional loan committees that meet weekly to consider loans ranging in amounts of $2.0 million to $5.0 million , and a senior loan committee, consisting of certain executive and senior officers, that meets weekly to consider loans ranging in amounts from $5.0 million to $10.0 million , depending on risk rating and credit action required. A directors’ loan committee of Chemical Bank, consisting of eight independent members of the board of directors of Chemical Bank, the chief executive officer of Chemical Bank and the chief credit officer of Chemical Bank, meets bi-weekly to consider loans in amounts over $10.0 million , and certain loans under $10.0 million depending on a loan’s risk rating and credit action required. Loans over $25.0 million require the approval of the board of directors of Chemical Bank. The majority of the Corporation’s consumer loan portfolio is comprised of secured loans that are relatively small. The Corporation’s consumer loan portfolio has a centralized approval process which utilizes standardized underwriting criteria. The ongoing measurement of credit quality of the consumer loan portfolio is largely done on an exception basis. If payments are made on schedule, as agreed, then no further monitoring is performed. However, if delinquency occurs, the delinquent loans are turned over to the Corporation’s collection department for resolution, resulting in repossession or foreclosure if payments are not brought current. Credit quality for the entire consumer loan portfolio is measured by the periodic delinquency rate, nonaccrual amounts and actual losses incurred. Loans in the commercial loan portfolio tend to be larger and more complex than those in the consumer loan portfolio, and therefore, are subject to more intensive monitoring. All loans in the commercial loan portfolio have an assigned relationship manager, and most borrowers provide periodic financial and operating information that allows the relationship managers to stay abreast of credit quality during the life of the loans. The risk ratings of loans in the commercial loan portfolio are reassessed at least annually, with loans below an acceptable risk rating reassessed more frequently and reviewed by various loan committees within the Corporation at least quarterly. The Corporation maintains a centralized independent loan review function that monitors the approval process and ongoing asset quality of the loan portfolio, including the accuracy of loan grades. The Corporation also maintains an independent appraisal review function that participates in the review of all appraisals obtained by the Corporation for loans in the commercial loan portfolio. Credit Quality Indicators Commercial Loan Portfolio Risk categories for the Corporation's commercial loan portfolio establish the credit quality of a borrower by measuring liquidity, debt capacity, coverage and payment behavior as shown in the borrower's financial statements. The risk categories also measure the quality of the borrower's management and the repayment support offered by any guarantors. Risk categories for the Corporation's commercial loan portfolio are described as follows: Pass: Includes all loans without weaknesses or potential weaknesses identified in the categories of special mention, substandard or doubtful. Special Mention: Loans with potential credit weakness or credit deficiency, which, if not corrected, pose an unwarranted financial risk that could weaken the loan by adversely impacting the future repayment ability of the borrower. Substandard: Loans with a well-defined weakness, or weaknesses, such as loans to borrowers who may be experiencing losses from operations or inadequate liquidity of a degree and duration that jeopardizes the orderly repayment of the loan. Substandard loans also are distinguished by the distinct possibility of loss in the future if these weaknesses are not corrected. Doubtful: Loans with all the characteristics of a loan classified as Substandard, with the added characteristic that credit weaknesses make collection in full highly questionable and improbable. The following schedule presents the recorded investment of loans in the commercial loan portfolio by credit risk categories at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Pass Special Mention Substandard Doubtful Total March 31, 2017 Originated Portfolio: Commercial $ 1,902,773 $ 34,018 $ 52,818 $ — $ 1,989,609 Commercial real estate 2,040,155 37,528 36,856 1 2,114,540 Real estate construction and land development 326,942 719 79 — 327,740 Subtotal 4,269,870 72,265 89,753 1 4,431,889 Acquired Portfolio: Commercial 1,171,260 39,079 53,625 35 1,263,999 Commercial real estate 1,841,116 52,038 89,912 165 1,983,231 Real estate construction and land development 122,593 1,887 1,591 — 126,071 Subtotal 3,134,969 93,004 145,128 200 3,373,301 Total $ 7,404,839 $ 165,269 $ 234,881 $ 201 $ 7,805,190 December 31, 2016 Originated Portfolio: Commercial $ 1,803,750 $ 44,809 $ 51,898 $ 1,069 $ 1,901,526 Commercial real estate 1,849,315 36,981 35,502 1 1,921,799 Real estate construction and land development 280,968 157 599 — 281,724 Subtotal 3,934,033 81,947 87,999 1,070 4,105,049 Acquired Portfolio: Commercial 1,218,848 46,643 50,283 — 1,315,774 Commercial real estate 1,897,011 61,441 92,636 253 2,051,341 Real estate construction and land development 117,505 1,982 2,561 — 122,048 Subtotal 3,233,364 110,066 145,480 253 3,489,163 Total $ 7,167,397 $ 192,013 $ 233,479 $ 1,323 $ 7,594,212 Consumer Loan Portfolio The Corporation evaluates the credit quality of loans in the consumer loan portfolio based on the performing or nonperforming status of the loan. Loans in the consumer loan portfolio that are performing in accordance with original contractual terms and are less than 90 days past due and accruing interest are considered to be in a performing status, while those that are in nonaccrual status, contractually past due 90 days or more as to interest or principal payments are considered to be in a nonperforming status. Loans accounted for under ASC 310-30, "acquired loans", that are not performing in accordance with contractual terms are not reported as nonperforming because these loans are recorded in pools at their net realizable value based on the principal and interest the Corporation expects to collect on these loans. The following schedule presents the recorded investment of loans in the consumer loan portfolio based on loans in a performing status and loans in a nonperforming status at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Residential Mortgage Consumer Installment Home Equity Total Consumer March 31, 2017 Originated Loans: Performing $ 1,587,627 $ 1,341,308 $ 588,728 $ 3,517,663 Nonperforming 6,749 755 2,713 10,217 Subtotal 1,594,376 1,342,063 591,441 3,527,880 Acquired Loans 1,539,089 138,994 262,239 1,940,322 Total $ 3,133,465 $ 1,481,057 $ 853,680 $ 5,468,202 December 31, 2016 Originated Loans: Performing $ 1,468,373 $ 1,281,709 $ 592,071 $ 3,342,153 Nonperforming 6,969 879 3,351 11,199 Subtotal 1,475,342 1,282,588 595,422 3,353,352 Acquired Loans 1,611,132 151,296 280,787 2,043,215 Total $ 3,086,474 $ 1,433,884 $ 876,209 $ 5,396,567 Nonperforming Assets and Past Due Loans Nonperforming assets consist of loans for which the accrual of interest has been discounted, other real estate owned acquired through acquisitions, other real estate owned obtained through foreclosure and other repossessed assets. Loans are considered past due or delinquent when the contractual principal or interest due in accordance with the terms of the loan agreement or any portion thereof remains unpaid after the due date of the scheduled payments. Loans outside of those accounted for under ASC 310-30 are classified as nonaccrual when, in the opinion of management, collection of principal or interest is doubtful. The accrual of interest is discontinued when a loan is placed in nonaccrual status and any payments received reduce the carrying value of the loan. A loan may be placed back on accrual status if all contractual payments have been received and collection of future principal and interest payments are no longer doubtful. Acquired loans that are not performing in accordance with contractual terms are not reported as nonperforming because these loans are recorded in pools at their net realizable value based on the principal and interest the Corporation expects to collect on these loans. A summary of nonperforming loans follows: (Dollars in thousands) March 31, December 31, Nonperforming assets Nonaccrual loans: Commercial $ 16,717 $ 13,178 Commercial real estate 20,828 19,877 Real estate construction and land development 79 80 Residential mortgage 6,749 6,969 Consumer installment 755 879 Home equity 2,713 3,351 Total nonaccrual loans 47,841 44,334 Other real estate owned and repossessed assets 16,395 17,187 Total nonperforming assets $ 64,236 $ 61,521 Accruing loans contractually past due 90 days or more as to interest or principal payments, excluding acquired loans accounted for under ASC 310-30 Commercial 1,823 11 Commercial real estate 700 277 Home equity 1,169 995 Total accruing loans contractually past due 90 days or more as to interest or principal payments, excluding acquired loans accounted for under ASC 310-30 $ 3,692 $ 1,283 The Corporation’s nonaccrual loans at March 31, 2017 and December 31, 2016 included $27.9 million and $30.5 million , respectively, of nonaccrual TDRs. The Corporation had $5.1 million of residential mortgage loans that were in the process of foreclosure at March 31, 2017 , compared to $7.3 million at December 31, 2016 . Loan delinquency, excluding acquired loans accounted for under ASC 310-30, was as follows: (Dollars in thousands) 30-59 days past due 60-89 days past due 90 days or more past due Total past due Current Total loans 90 days or more past due and still accruing March 31, 2017 Originated Portfolio: Commercial $ 10,603 $ 9,411 $ 8,661 $ 28,675 $ 1,960,934 $ 1,989,609 $ 1,823 Commercial real estate 9,712 2,625 6,016 18,353 2,096,187 2,114,540 700 Real estate construction and land development 3,495 1,770 — 5,265 322,475 327,740 — Residential mortgage 12,918 731 941 14,590 1,579,786 1,594,376 — Consumer installment 2,805 275 235 3,315 1,338,748 1,342,063 — Home equity 3,976 552 1,536 6,064 585,377 591,441 1,169 Total $ 43,509 $ 15,364 $ 17,389 $ 76,262 $ 7,883,507 $ 7,959,769 $ 3,692 December 31, 2016 Originated Portfolio: Commercial $ 10,421 $ 4,842 $ 3,641 $ 18,904 $ 1,882,622 $ 1,901,526 $ 11 Commercial real estate 6,551 1,589 5,165 13,305 1,908,494 1,921,799 277 Real estate construction and land development 2,721 499 — 3,220 278,504 281,724 — Residential mortgage 3,147 62 1,752 4,961 1,470,381 1,475,342 — Consumer installment 3,991 675 238 4,904 1,277,684 1,282,588 — Home equity 3,097 893 2,349 6,339 589,083 595,422 995 Total $ 29,928 $ 8,560 $ 13,145 $ 51,633 $ 7,406,768 $ 7,458,401 $ 1,283 Impaired Loans A loan is impaired when, based on current information and events, it is probable that the Corporation will be unable to collect all amounts due according to the contractual terms of the loan agreement. Impaired loans include nonperforming loans and all TDRs. Impaired loans are accounted for at the lower of the present value of expected cash flows or the estimated fair value of the collateral. When the present value of expected cash flows or the fair value of the collateral of an impaired loan not accounted for under ASC 310-30 is less than the amount of unpaid principal outstanding on the loan, the recorded principal balance of the loan is reduced to its carrying value through either a specific allowance for loan loss or a partial charge-off of the loan balance. The following schedules present impaired loans by classes of loans at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Recorded Investment Unpaid Principal Balance Related Valuation Allowance March 31, 2017 Impaired loans with a valuation allowance: Commercial $ 26,201 $ 29,804 $ 2,468 Commercial real estate 20,416 25,875 1,251 Real estate construction and land development 164 164 2 Residential mortgage 16,944 16,944 1,162 Consumer installment 799 799 102 Home equity 4,296 4,296 655 Subtotal 68,820 77,882 5,640 Impaired loans with no related valuation allowance: Commercial 9,028 14,910 — Commercial real estate 22,791 26,569 — Real estate construction and land development 79 79 — Residential mortgage 3,607 3,607 — Consumer installment 62 62 — Home equity 512 512 — Subtotal 36,079 45,739 — Total impaired loans: Commercial 35,229 44,714 2,468 Commercial real estate 43,207 52,444 1,251 Real estate construction and land development 243 243 2 Residential mortgage 20,551 20,551 1,162 Consumer installment 861 861 102 Home equity 4,808 4,808 655 Total $ 104,899 $ 123,621 $ 5,640 December 31, 2016 Impaired loans with a valuation allowance: Commercial $ 28,925 $ 33,209 $ 3,128 Commercial real estate 21,318 27,558 2,102 Real estate construction and land development 177 177 4 Residential mortgage 20,864 20,864 3,528 Consumer installment 879 879 240 Home equity 2,577 2,577 390 Subtotal 74,740 85,264 9,392 Impaired loans with no related valuation allowance: Commercial 7,435 11,153 — Commercial real estate 20,588 23,535 — Real estate construction and land development 80 80 — Residential mortgage 3,252 3,252 — Home equity 774 774 — Subtotal 32,129 38,794 — Total impaired loans: Commercial 36,360 44,362 3,128 Commercial real estate 41,906 51,093 2,102 Real estate construction and land development 257 257 4 Residential mortgage 24,116 24,116 3,528 Consumer installment 879 879 240 Home equity 3,351 3,351 390 Total $ 106,869 $ 124,058 $ 9,392 The following schedule presents additional information regarding impaired loans by classes of loans segregated by those requiring a valuation allowance and those not requiring a valuation allowance for the three months ended March 31, 2017 and 2016 , and the respective interest income amounts recognized: Three Months Ended March 31, 2017 Three Months Ended March 31, 2016 (Dollars in thousands) Average recorded investment Interest income recognized while on impaired status Average recorded investment Interest income recognized while on impaired status Impaired loans with a valuation allowance: Commercial $ 25,712 $ — $ 10,551 $ — Commercial real estate 20,035 — 7,592 — Real estate construction and land development 161 — — — Residential mortgage 17,398 264 20,988 333 Consumer installment 780 — — — Home equity 4,071 — — — Subtotal $ 68,157 $ 264 $ 39,131 $ 333 Impaired loans with no related valuation allowance: Commercial $ 9,297 $ 255 $ 31,404 $ 277 Commercial real estate 23,473 306 45,737 380 Real estate construction and land development 81 2 918 6 Residential mortgage 3,808 — 5,149 — Consumer installment 215 — 340 — Home equity 880 — 2,388 — Subtotal $ 37,754 $ 563 $ 85,936 $ 663 Total impaired loans: Commercial $ 35,009 $ 255 $ 41,955 $ 277 Commercial real estate 43,508 306 53,329 380 Real estate construction and land development 242 2 918 6 Residential mortgage 21,206 264 26,137 333 Consumer installment 995 — 340 — Home equity 4,951 — 2,388 — Total $ 105,911 $ 827 $ 125,067 $ 996 The difference between an impaired loan’s recorded investment and the unpaid principal balance for originated loans represents a partial charge-off resulting from a confirmed loss due to the value of the collateral securing the loan being below the loan balance and management’s assessment that full collection of the loan balance is not likely. Impaired loans included $57.1 million and $62.5 million at March 31, 2017 and December 31, 2016 , respectively, of accruing TDRs. Loans Modified Under Troubled Debt Restructurings (TDRs) The following tables present the recorded investment of loans modified into TDRs during the three months ended March 31, 2017 and 2016 by type of concession granted. In cases where more than one type of concession was granted, the loans were categorized based on the most significant concession. Concession type (Dollars in thousands) Principal Interest Forbearance Total Pre-modification recorded investment Post-modification recorded investment For the three months ended March 31, 2017 Commercial loan portfolio: Commercial $ 50 $ 1,101 $ 579 5 $ 1,739 $ 1,730 Commercial real estate 447 75 — 3 522 522 Subtotal 497 1,176 579 8 2,261 2,252 Consumer loan portfolio: Residential mortgage 98 — — 1 98 98 Consumer installment 10 — — 2 11 10 Home equity 111 — — 1 165 111 Subtotal 219 — — 4 274 219 Total loans $ 716 $ 1,176 $ 579 12 $ 2,535 $ 2,471 For the three months ended March 31, 2016 Commercial loan portfolio: Commercial $ 3,832 $ — $ — 7 $ 3,832 $ 3,832 Commercial real estate 987 — — 4 987 987 Subtotal 4,819 — — 11 4,819 4,819 Consumer loan portfolio: Residential mortgage 105 — — 1 105 105 Consumer installment 33 — — 4 33 33 Home equity 29 37 — 2 66 66 Subtotal 167 37 — 7 204 204 Total loans $ 4,986 $ 37 $ — 18 $ 5,023 $ 5,023 The pre-modification and post-modification recorded investment represents amounts as of the date of loan modification. The difference between the pre-modification and post-modification recorded investment of residential mortgage TDRs represents impairment recognized by the Corporation through the provision for loan losses computed based on a loan's post-modification present value of expected future cash flows discounted at the loan's original effective interest rate. The following schedule presents the Corporation's TDRs at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Accruing TDRs Nonaccrual TDRs Total March 31, 2017 Commercial loan portfolio $ 41,055 $ 23,842 $ 64,897 Consumer loan portfolio 16,003 4,100 20,103 Total $ 57,058 $ 27,942 $ 85,000 December 31, 2016 Commercial loan portfolio $ 45,388 $ 25,397 $ 70,785 Consumer loan portfolio 17,147 5,134 22,281 Total $ 62,535 $ 30,531 $ 93,066 The following schedule includes TDRs for which there was a payment default during the three months ended March 31, 2017 and 2016 , whereby the borrower was past due with respect to principal and/or interest for 90 days or more, and the loan became a TDR during the twelve-month period prior to the default: Three Months Ended March 31, 2017 Three Months Ended March 31, 2016 (Dollars in thousands) Number of loans Principal balance Number of loans Principal balance Commercial loan portfolio: Commercial 3 $ 620 — $ — Commercial real estate — — 1 933 Subtotal - Commercial loan portfolio 3 620 1 933 Consumer loan portfolio (residential mortgage) 2 105 1 — Total 5 $ 725 2 $ 933 At March 31, 2017, commitments to lend additional funds to borrowers whose terms have been modified in TDRs totaled $2.7 million . Allowance for Loan Losses The following schedule presents, by loan portfolio segment, the changes in the allowance for the three months ended March 31, 2017 and 2016 , and details regarding the balance in the allowance and the recorded investment in loans at March 31, 2017 by impairment evaluation method. (Dollars in thousands) Commercial Loan Portfolio Consumer Loan Portfolio Total Changes in allowance for loan losses for the three months ended March 31, 2017: Beginning balance $ 51,201 $ 27,067 $ 78,268 Provision for loan losses 4,392 (342 ) 4,050 Charge-offs (2,691 ) (2,883 ) (5,574 ) Recoveries 1,413 617 2,030 Ending balance $ 54,315 $ 24,459 $ 78,774 Changes in allowance for loan losses for the three months ended March 31, 2016: Beginning balance $ 47,234 $ 26,094 $ 73,328 Provision for loan losses 1,000 500 1,500 Charge-offs (3,896 ) (1,562 ) (5,458 ) Recoveries 330 618 948 Ending balance $ 44,668 $ 25,650 $ 70,318 Allowance for loan losses balance at March 31, 2017 attributable to: Loans individually evaluated for impairment $ 3,721 $ 1,919 $ 5,640 Loans collectively evaluated for impairment 50,594 22,540 73,134 Loans acquired with deteriorated credit quality — — — Total $ 54,315 $ 24,459 $ 78,774 Recorded investment (loan balance) at March 31, 2017: Loans individually evaluated for impairment $ 78,679 $ 26,220 $ 104,899 Loans collectively evaluated for impairment 4,353,210 3,501,660 7,854,870 Loans acquired with deteriorated credit quality 3,373,301 1,940,322 5,313,623 Total $ 7,805,190 $ 5,468,202 $ 13,273,392 The following schedule presents, by loan portfolio segment, details regarding the balance in the allowance and the recorded investment in loans at December 31, 2016 by impairment evaluation method. (Dollars in thousands) Commercial Loan Portfolio Consumer Loan Portfolio Total Allowance for loan losses balance at December 31, 2016 attributable to: Loans individually evaluated for impairment $ 5,234 $ 4,158 $ 9,392 Loans collectively evaluated for impairment 45,967 22,909 68,876 Loans acquired with deteriorated credit quality — — — Total $ 51,201 $ 27,067 $ 78,268 Recorded investment (loan balance) at December 31, 2016: Loans individually evaluated for impairment $ 78,523 $ 28,346 $ 106,869 Loans collectively evaluated for impairment 4,026,526 3,325,006 7,351,532 Loans acquired with deteriorated credit quality 3,489,163 2,043,215 5,532,378 Total $ 7,594,212 $ 5,396,567 $ 12,990,779

Other Real Estate Owned and Rep

Other Real Estate Owned and Repossessed Assets	3 Months Ended
	Mar. 31, 2017
Other Real Estate [Abstract]
Other Real Estate Owned and Repossessed Assets	Other Real Estate Owned and Repossessed Assets Changes in other real estate owned and repossessed assets, included in interest receivable and other assets on the consolidated statements of financial position, were as follows: (Dollars in thousands) Other real estate Repossessed Balance at January 1, 2017 $ 16,812 $ 375 Other additions (1) 3,119 1,162 Net payments received (39 ) — Disposals (3,728 ) (1,037 ) Write-downs (269 ) — Balance at March 31, 2017 $ 15,895 $ 500 Balance at January 1, 2016 $ 9,716 $ 219 Other additions (1) 938 729 Net payments received (185 ) (11 ) Disposals (1,371 ) (620 ) Write-downs (167 ) — Balance at March 31, 2016 $ 8,931 $ 317 (1) Includes loans transferred to other real estate owned and other repossessed assets. At March 31, 2017 the Corporation had $1.2 million of other real estate owned and repossessed assets as a result of obtaining physical possession in accordance with ASU No. 2014-04, Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans Upon Foreclosure. In addition, there were $5.1 million of consumer mortgage loans secured by residential real estate properties for which formal foreclosure proceedings are in process as of March 31, 2017 . Income and expenses related to other real estate owned and repossessed assets, recorded as a component of "Other expense" in the Consolidated Statements of Income, were as follows: (Dollars in thousands) Other real estate owned Repossessed assets For the three months ended March 31, 2017 Net gain (loss) on sale $ 1,047 $ (78 ) Write-downs (269 ) — Net operating expenses (508 ) (3 ) Total $ 270 $ (81 ) For the three months ended March 31, 2016 Net gain (loss) on sale $ 722 $ (8 ) Write-downs (167 ) — Net operating expenses (153 ) (5 ) Total $ 402 $ (13 )

Goodwill

Goodwill	3 Months Ended
	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill Goodwill was $1.13 billion for the periods ended March 31, 2017 and December 31, 2016 , respectively. Goodwill recorded is primarily attributable to the synergies and economies of scale expected from combining the operations of the Corporation and acquired organizations. The Corporation recorded goodwill in the amount of $846.7 million related to the merger with Talmer completed on August 31, 2016. Goodwill is not amortized but is evaluated at least annually for impairment. The Corporation’s most recent annual goodwill impairment review performed as of October 31, 2016 did not indicate that an impairment of goodwill existed. The Corporation also determined that no triggering events have occurred that indicated impairment from the most recent valuation date through March 31, 2017 and that the Corporation's goodwill was no t impaired at March 31, 2017 .

Loan Servicing Rights

Loan Servicing Rights	3 Months Ended
	Mar. 31, 2017
Transfers and Servicing [Abstract]
Loan Servicing Rights	Loan Servicing Rights Loan servicing rights ("LSRs") are created as a result of selling residential mortgage and commercial real estate loans in the secondary market while retaining the right to service these loans and receive servicing income over the life of the loan, and from acquisitions of other banks that had LSRs. Loans serviced for others are not reported as assets in the Consolidated Statements of Financial Position. The Corporation elected to account for LSRs acquired related to the merger with Talmer under the fair value measurement method. Prior to January 1, 2017, the Corporation accounted for all other LSRs at the lower of cost or fair value ("Amortized LSRs"). The Company elected as of January 1, 2017 to account for all previously Amortized LSRs under the fair value measurement method. This change in accounting policy resulted in a cumulative adjustment to retained earnings as of January 1, 2017 in the amount of $3.7 million . For further information on this election, refer to Footnote 1, Basis of Presentation and Accounting Policies. LSRs are established and recorded at the estimated fair value by calculating the present value of estimated future net servicing cash flows, taking into consideration actual and expected mortgage loan prepayment rates, discount rates, servicing costs, and other economic factors, which are determined based on current market conditions. The following table represents the activity for LSRs and the related fair value changes: For the three months ended March 31, 2017 (Dollars in thousands) Commercial Real Estate Mortgage Total Fair value, beginning of period $ 344 $ 47,741 $ 48,085 Transfers based on new accounting policy election — 15,891 15,891 Additions from loans sold with servicing retained — 1,753 1,753 Changes in fair value due to: Reductions from pay-offs, pay downs and run-off (24 ) (582 ) (606 ) Changes in estimates of fair value (1) — (519 ) (519 ) Fair value, end of period $ 320 $ 64,284 $ 64,604 Principal balance of loans serviced for others that have servicing capitalized $ 50,942 $ 7,253,396 $ 7,304,338 (1) Represents estimated LSR value change resulting primarily from market-driven changes in interest rates and prepayments. Included in "Mortgage banking revenue" in the Consolidated Statements of Income. During the three months ended March 31, 2016, the Corporation accounted for LSRs using the amortization method. Activity for LSRs and the related valuation allowance for the three months ended March 31, 2016 are as follows: (Dollars in thousands) For the three months ended March 31, 2016 Balance at beginning of period $ 11,122 Additions 331 Amortization (975 ) Balance at end of period $ 10,478 Expected and actual loan prepayment speeds are the most significant factors driving the fair value of loan servicing rights. The following table presents assumptions utilized in determining the fair value of loan servicing rights as of March 31, 2017 and December 31, 2016 . Mortgage As of March 31, 2017 Prepayment speed 0.0 - 36.6% Weighted average (“WA”) discount rate 10.1 % Cost to service/per year $ 65 Ancillary income/per year $ 31 WA float range 0.98 % As of December 31, 2016 Prepayment speed 0.0 - 99.8% WA discount rate 10.1 % Cost to service/per year $65-$90 Ancillary income/per year $ 28 WA float range 1.0 % The Corporation realized total loan servicing fee income, included in "Mortgage banking revenue" in the Consolidated Statements of Income, of $4.5 million and $1.3 million for the three months ended March 31, 2017 and 2016 , respectively.

Other Intangible Assets

Other Intangible Assets	3 Months Ended
	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Other Intangible Assets	Other Intangible Assets The following table shows the net carrying value of the Corporation’s other intangible assets: (Dollars in thousands) March 31, December 31, Core deposit intangible assets $ 38,723 $ 40,211 Non-compete intangible assets 125 — Total other intangible assets $ 38,848 $ 40,211 The following table sets forth the carrying amount and accumulated amortization of core deposit intangible assets that are amortizable and arose from business combinations or other acquisitions: (Dollars in thousands) March 31, December 31, Gross original amount $ 59,143 $ 59,143 Accumulated amortization 20,420 18,932 Net carrying amount $ 38,723 $ 40,211 Amortization expense recognized on core deposit intangible assets was $1.5 million and $1.1 million for the three months ended March 31, 2017 and 2016, respectively. The estimated future amortization expense on core deposit intangible assets for periods ending after March 31, 2017 is as follows: 2017 — $4.5 million ; 2018 — $5.7 million ; 2019 — $5.4 million ; 2020 — $4.9 million ; 2021 — $4.5 million ; 2022 and thereafter — $13.8 million .

Derivative Instruments and Bala

Derivative Instruments and Balance Sheet Offsetting	3 Months Ended
	Mar. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Balance Sheet Offsetting	Derivative Instruments and Balance Sheet Offsetting In the normal course of business, the Corporation enters into various transactions involving derivative instruments to manage exposure to fluctuations in interest rates and to meet the financing needs of customers (customer-initiated derivatives). These financial instruments involve, to varying degrees, elements of market and credit risk. Market and credit risk are included in the determination of fair value. Commitments to fund mortgage loans (interest rate locks) to be sold into the secondary market and forward commitments for the future delivery of mortgage loans to third party investors are considered derivatives. It is the Corporation’s practice to enter into forward commitments for the future delivery of mortgage loans when interest rate lock commitments are entered into in order to economically hedge the effect of changes in interest rates resulting from its commitments to fund the loans. The Corporation enters into interest rate derivatives to provide a service to certain qualifying customers to help facilitate their respective risk management strategies, customer-initiated derivatives, and, therefore, are not used for interest rate risk management purposes. The Corporation generally takes offsetting positions with dealer counterparts to mitigate the inherent risk. Income primarily results from the spread between the customer derivative and the offsetting dealer positions. The Corporation additionally has written and purchased option derivatives consisting of instruments to facilitate an equity-linked time deposit product (the "Power Equity CD"). The Power Equity CD is a time deposit that provides the purchaser a guaranteed return of principal at maturity plus a potential equity return (a written option), while the Corporation receives a known stream of funds based on the equity return (a purchased option). The written and purchased options are mirror derivative instruments which are carried at fair value on the Consolidated Statements of Financial Position. The following table presents the notional amount and fair value of the Corporation’s derivative instruments held or issued in connection with customer-initiated and mortgage banking activities. March 31, 2017 December 31, 2016 Fair Value Fair Value (Dollars in thousands) Notional Amount (1) Gross Derivative Assets (2) Gross Derivative Liabilities (2) Notional Amount (1) Gross Derivative Assets (2) Gross Derivative Liabilities (2) Customer-initiated and mortgage banking derivatives: Customer-initiated derivatives $ 837,903 $ 6,377 $ 6,342 $ 600,598 $ 4,406 $ 4,141 Forward contracts related to mortgage loans to be delivered for sale 121,008 — 342 140,155 635 — Interest rate lock commitments 96,764 2,178 — 76,034 956 — Power Equity CD 37,635 2,234 2,234 36,807 2,218 2,218 Total gross derivatives $ 1,093,310 $ 10,789 $ 8,918 $ 853,594 $ 8,215 $ 6,359 (1) Notional or contract amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the Consolidated Statements of Financial Position. (2) Derivative assets are included within "Other assets" and derivative liabilities are included within "Other liabilities" on the Consolidated Statements of Financial Position. Included in the fair value of the derivative assets are credit valuation adjustments for counterparty credit risk totaling $138 thousand at March 31, 2017 and $99 thousand at December 31, 2016 . In the normal course of business, the Corporation may decide to settle a forward contract rather than fulfill the contract. Cash received or paid in this settlement manner is included in "Mortgage banking revenue" in the Consolidated Statements of Income and is considered a cost of executing a forward contract. The following table presents the net gains (losses) related to derivative instruments reflecting the changes in fair value. Three Months Ended March 31, (Dollars in thousands) Location of Gain (Loss) 2017 2016 Forward contracts related to mortgage loans to be delivered for sale Mortgage banking revenue $ (977 ) $ (233 ) Interest rate lock commitments Mortgage banking revenue 1,223 161 Customer-initiated derivatives Other noninterest income (231 ) — Total gain (loss) recognized in income $ 15 $ (72 ) Methods and assumptions used by the Corporation in estimating the fair value of its forward contracts, interest rate lock commitments and customer-initiated derivatives are discussed in Note 3: Fair Value Measurements. Balance Sheet Offsetting Certain financial instruments, including customer-initiated derivatives, may be eligible for offset in the Consolidated Statements of Financial Position and/or subject to master netting arrangements or similar agreements. The Corporation is party to master netting arrangements with its financial institution counterparties; however, the Corporation does not offset assets and liabilities under these arrangements for financial statement presentation purposes based on an accounting policy election. The tables below present information about the Corporation’s financial instruments that are eligible for offset. Gross amounts not offset in the (Dollars in thousands) Gross Gross amounts Net amounts Financial Collateral Net March 31, 2017 Offsetting derivative assets Derivative assets $ 6,355 $ — $ 6,355 $ — $ (450 ) $ 5,905 Offsetting derivative liabilities Derivative liabilities 6,342 — 6,342 — 7,506 (1,164 ) December 31, 2016 Offsetting derivative assets Derivative assets $ 4,405 $ — $ 4,405 $ — $ — $ 4,405 Offsetting derivative liabilities Derivative liabilities 4,141 — 4,141 — 2,550 1,591

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	Commitments, Contingencies and Guarantees Commitments In the normal course of business, the Corporation offers a variety of financial instruments containing credit risk that are not required to be reflected in the Consolidated Statements of Financial Position. These financial instruments include outstanding commitments to extend credit, approved but undisbursed loans (undisbursed loan commitments), credit lines, commercial letters of credit and standby letters of credit. The Corporation has risk management policies to identify, monitor and limit exposure to credit risk. To mitigate credit risk for these financial guarantees, the Corporation generally determines the need for specific covenant, guarantee and collateral requirements on a case-by-case basis, depending on the nature of the financial instrument and the customer’s creditworthiness. At March 31, 2017 and December 31, 2016 , the Corporation had $118.4 million and $118.9 million , respectively, of outstanding financial and performance standby letters of credit. The majority of these standby letters of credit are collateralized. The Corporation determined that there were no potential losses from standby letters of credit at March 31, 2017 and December 31, 2016 . Commitments to extend credit are agreements to lend to a customer provided there is no violation of any condition established in the commitment. Commitments generally have fixed expiration dates or other termination clauses and may not require payment of a fee. Since many commitments expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Corporation evaluates each customer's creditworthiness on an individual basis. The amount of collateral obtained, if deemed necessary by the Corporation upon extension of credit, is based on management's credit evaluation of the counterparty. The collateral held varies, but may include securities, real estate, accounts receivable, inventory, plant or equipment. Unfunded commitments under commercial lines of credit, revolving credit lines and overdraft protection agreements are included in commitments to extend credit. These lines of credit are generally not collateralized, usually do not contain a specified maturity date and may be drawn upon only to the total extent to which the Corporation is committed. At March 31, 2017 and December 31, 2016 , the Corporation had $2.65 billion and $2.70 billion , respectively, of commitments to extend credit. The Corporation had undisbursed loan commitments of $565.6 million and $578.2 million at March 31, 2017 and December 31, 2016 , respectively. Undisbursed loan commitments are not included in loans on the Consolidated Statements of Financial Position. The majority of undisbursed loan commitments will be funded and convert to a portfolio loan within a one year period. The allowance for credit losses on lending-related commitments included $1.0 million and $1.3 million at March 31, 2017 and December 31, 2016 , respectively, for probable credit losses inherent in the Corporation's unused commitments and was recorded in "Interest payable and other liabilities" in the Consolidated Statements of Financial Position. Contingencies and Guarantees The Corporation has originated and sold certain loans, and additionally acquired the potential liability for those historical originated and sold loans by Talmer, for which the buyer has limited recourse to us in the event the loans do not perform as specified in the agreements. These loans had an outstanding balance of $15.4 million and $16.9 million at March 31, 2017 and December 31, 2016 , respectively. The maximum potential amount of undiscounted future payments that the Corporation could be required to make in the event of nonperformance by the borrower totaled $14.8 million and $16.1 million at March 31, 2017 and December 31, 2016 , respectively. In the event of nonperformance, the Corporation has rights to the underlying collateral securing the loans. At both March 31, 2017 and December 31, 2016 , the Corporation had recorded a liability of $200 thousand in connection with the recourse agreements, recorded in "Interest payable and other liabilities" in the Consolidated Statements of Financial Position. Representations and Warranties In connection with the Corporation's mortgage banking loan sales, and the historical sales of Talmer, the Corporation makes certain representations and warranties that the loans meet certain criteria, such as collateral type and underwriting standards. The Corporation may be required to repurchase individual loans and/or indemnify the purchaser against losses if the loan fails to meet established criteria. At March 31, 2017 and December 31, 2016 , respectively, the liability recorded in connection with these representations and warranties totaled $5.7 million and $6.5 million , respectively. A summary of the reserve for unfunded commitments of the Corporation is as follows: For the three months ended March 31, (Dollars in thousands) 2017 2016 Reserve balance at beginning of period $ 6,459 $ 4,048 Reserve reduction (770 ) (150 ) Charge-offs — (73 ) Ending reserve balance $ 5,689 $ 3,825 (Dollars in thousands) March 31, 2017 December 31, 2016 Reserve balance Liability for specific claims 529 730 General allowance 5,160 5,729 Total reserve balance $ 5,689 $ 6,459

Borrowings

Borrowings	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Borrowings	Borrowings A summary of the Corporation's short- and long-term borrowings follows: March 31, December 31, (Dollars in thousands) Amount Weighted Average Rate (1) Amount Weighted Average Rate (1) Securities sold under agreements to repurchase with customers: Securities sold under agreements to repurchase with customers $ 398,910 0.18 % $ 343,047 0.16 % Short-term borrowings: FHLB advances: 0.66% - 0.89% fixed-rate notes 900,000 0.79 825,000 0.65 Long-term borrowings: FHLB advances: 0.92% - 7.44% fixed-rate notes due 2017 to 2020 (2) 386,417 2.11 438,538 1.24 Securities sold under agreements to repurchase: 1.48% - 2.75% fixed-rate notes due in 2017 (3) 9,093 1.29 19,144 3.17 Line-of-credit: floating-rate based on one-month LIBOR plus 1.75% 79,783 2.53 124,625 2.52 Subordinated debt obligations: floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035 (4) 11,320 3.30 11,285 3.14 Subordinated debt obligations: floating-rate based on three-month LIBOR plus 3.25% due in 2032 (5) 4,263 4.40 4,255 4.25 Total long-term borrowings 490,876 2.21 597,847 1.63 Total borrowings $ 1,789,786 1.04 % $ 1,765,894 0.89 % (1) Weighted average rate presented is the contractual rate which excludes premiums and discounts related to purchase accounting. (2) The March 31, 2017 balances include advances payable of $385.9 million and purchase accounting premiums of $0.6 million . The December 31, 2016 balance includes advances payable of $437.8 million and purchase accounting premiums of $0.7 million . (3) The March 31, 2017 balance includes advances payable of $9.0 million and purchase accounting premiums of $0.1 million . The December 31, 2016 balance includes advance payable of $19.0 million and purchase accounting premiums of $0.1 million . (4) The March 31, 2017 balance includes advances payable of $15.0 million and purchase accounting discounts of $3.7 million . The December 31, 2016 balance includes advances payable of $15.0 million and purchase accounting discounts of $3.7 million . (5) The March 31, 2017 balance includes advances payable of $5.0 million and purchase accounting discounts of $0.7 million . The December 31, 2016 balance includes advances payable of $5.0 million and purchase accounting discounts of $0.7 million . Chemical Bank is a member of the FHLB, which provides short- and long-term funding collateralized by mortgage related assets to its members. Each advance is payable at its maturity date, with a prepayment penalty for fixed-rate advances. The Corporation's FHLB advances, including both short-term and long-term, require monthly interest payments and are collateralized by commercial and residential mortgage loans totaling $5.17 billion as of March 31, 2017 . The Corporation's additional borrowing availability through the FHLB, subject to the FHLB's credit requirements and policies and based on the amount of FHLB stock owned by the Corporation, was $53.2 million at March 31, 2017 . Securities sold under agreements to repurchase are with an unaffiliated financial institution and are secured by available for-sale-securities. The Corporation's securities sold under agreements to repurchase do not qualify as sales for accounting purposes. The remaining contractual maturity, excluding purchase accounting adjustments, of long-term securities under agreement to repurchase, is as follows: March 31, 2017 Remaining Contractual Maturities of the Agreements (Dollars in thousands) Overnight and continuous Up to 30 Days 30-90 Days Greater than 90 Days Total Securities sold under agreements to repurchase $ — $ — $ — $ 9,000 $ 9,000 Total borrowings $ — $ — $ — $ 9,000 $ 9,000 Amounts related to securities sold under agreements to repurchase not included in offsetting disclosure in Footnote 10 $ 9,000 The line-of-credit agreement contains certain restrictive covenants. The Corporation was in compliance with all of the covenants at March 31, 2017 .

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Corporation records its federal income tax expense using its estimate of the effective income tax rate expected for the full year and applies that rate on a year-to-date basis. The fluctuations in the Corporation's effective federal income tax rate reflect changes each period in the proportion of interest income exempt from federal taxation, nondeductible transaction costs and other nondeductible expenses relative to pretax income and tax credits. A reconciliation of expected income tax expense at the federal statutory income tax rate and the amounts recorded in the Consolidated Financial Statements were as follows: Three Months Ended March 31, 2017 2016 (Dollars in thousands) Amount Rate Amount Rate Tax at statutory rate $ 20,951 35.0 % $ 11,677 35.0 % Changes resulting from: Tax-exempt interest income (1,757 ) (2.9 ) (1,139 ) (3.4 ) State taxes, net of federal benefit 212 0.4 — — Change in valuation allowance 11 — — — Bank-owned life insurance adjustments (344 ) (0.6 ) (68 ) (0.2 ) Income tax credits, net (695 ) (1.2 ) (797 ) (2.4 ) Tax benefits in excess of compensation costs on share-based payments (6,134 ) (10.2 ) (343 ) (1.0 ) Other, net 13 — 427 1.2 Income tax expense $ 12,257 20.5 % $ 9,757 29.2 %

Share-Based Compensation

Share-Based Compensation	3 Months Ended
	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation The Corporation maintains share-based compensation plans under which it periodically grants share-based awards for a fixed number of shares to certain officers of the Corporation. The fair value of share-based awards is recognized as compensation expense over the requisite service or performance period. During the three-month periods ended March 31, 2017 and 2016 , share-based compensation expense related to share-based awards totaled $3.8 million and $0.8 million , respectively. During the three months ended March 31, 2017 and 2016 , excess tax benefit realized from shared-based compensation transactions was $6.1 million and $0.3 million , respectively. During the three-month period ended March 31, 2017 , the Corporation granted options to purchase 126,695 shares of common stock, 159,462 restricted stock units and 13,300 shares of common stock to certain officers of the Corporation. On April 20, 2015, the shareholders of the Corporation approved the Stock Incentive Plan of 2015, which provides for 1,300,000 shares of the Corporation's common stock to be made available for future equity-based awards and canceled the amount of shares available for future grant under prior share-based compensation plans. At March 31, 2017 , there were 287,348 shares of common stock available for future grants under the Stock Incentive Plan of 2015. On April 26, 2017, the shareholders of the Corporation approved the Stock Incentive Plan of 2017, which provides for 1,750,000 shares of the Corporation's common stock to be made available for future equity-based awards and canceled the amount of shares available for future grant under prior share-based compensation plans. Stock Options The Corporation issues stock options to certain officers from time to time. The exercise price on stock options equals the current market price of the Corporation's common stock on the date of grant and stock options expire ten years from the date of grant. Stock options granted after 2012 vest ratably over a five -year period. Stock options granted prior to 2013 generally vest ratably over a three -year period. Stock options granted prior to 2016 fully vested upon the merger with Talmer. Stock options assumed by the Corporation in the merger with Talmer were fully vested prior to assumption. A summary of activity for the Corporation’s stock options as of and for the three months ended March 31, 2017 is presented below: Non-Vested Stock Options Outstanding Stock Options Outstanding Number of Options Weighted- Average Exercise Price Per Share Weighted- Average Grant Date Fair Value Per Share Number of Options Weighted- Average Exercise Price Per Share Outstanding at December 31, 2016 407,939 $ 32.81 $ 6.15 2,453,395 $ 21.41 Granted 126,695 53.72 10.05 126,695 53.72 Exercised — — — (1,210,264 ) 15.92 Vested (81,584 ) 32.81 6.15 — — Forfeited/expired (3,940 ) 32.81 6.15 (3,940 ) 32.81 Outstanding at March 31, 2017 449,110 $ 38.71 $ 7.25 1,365,886 $ 29.24 Exercisable/vested at March 31, 2017 916,776 $ 24.60 The weighted-average remaining contractual terms were 6.9 years for all outstanding stock options and 5.7 years for exercisable stock options at March 31, 2017 . The intrinsic value of all outstanding in-the-money stock options and exercisable in-the-money stock options was $29.0 million and $24.3 million , respectively, at March 31, 2017 . The aggregate intrinsic values of outstanding and exercisable options at March 31, 2017 were calculated based on the closing market price of the Corporation’s common stock on March 31, 2017 of $51.15 per share less the exercise price. Options with intrinsic values less than zero, or "out-of-the-money" options, are not included in the aggregate intrinsic value reported. The total intrinsic value of stock options for the three months ended March 31, 2016 was $11.0 million . Total cash received from options exercises during the three months ended March 31, 2017 and 2016 was $906 thousand and $498 thousand , respectively, resulting in the issuance of 496 thousand shares and 37 thousand shares, respectively. At March 31, 2017 , unrecognized compensation expense related to stock options totaled $3.2 million and is expected to be recognized over a remaining weighted average period of 4.3 years . The fair value of the stock options granted during the three months ended March 31, 2017 was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions. Expected dividend yield 3.32 % Risk-free interest rate 2.06 % Expected stock price volatility 26.9 % Expected life of options – in years 6.0 Weighted average fair value of options granted $ 10.05 The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant and the expected life of the options granted. Expected stock volatility was based on historical volatility of the Corporation's common stock over the expected life of the option. The expected life of the options represents the period of time that options granted are expected to be outstanding and is based primarily upon historical experience, including option exercise behavior. Because of the unpredictability of the assumptions required, the Black-Scholes (or any other valuation) model is incapable of accurately predicting the Corporation's common stock price or of placing an accurate present value on options to purchase its stock. In addition, the Black-Scholes model was designed to approximate value for types of options that are very different from those issued by the Corporation. In spite of any theoretical value that may be placed on a stock option grant, no value is possible under options issued by the Corporation without an increase in the market price per share of the Corporation's common stock over the market price per share of the Corporation's common stock at the date of grant. Restricted Stock Units The Corporation grants restricted stock performance units and restricted stock service-based units (collectively referred to as restricted stock units) to certain officers from time to time. The restricted stock performance units vest based on the Corporation achieving certain performance target levels and the grantee completing the requisite service period. The restricted stock performance units are eligible to vest from 0.5 x to 1.5 x the number of units originally granted depending on which, if any, of the performance target levels are met. However, if the minimum performance target levels are not achieved, no shares will become vested or be issued for that respective year’s restricted stock performance units. The restricted stock service-based units vest upon satisfaction of a service condition. Upon achievement of the performance target level and/or satisfaction of a service condition, as applicable, the restricted stock units are converted into shares of the Corporation’s common stock on a one-to-one basis. Compensation expense related to restricted stock units is recognized over the expected requisite performance or service period, as applicable. A summary of the activity for restricted stock units as of and for the three months ended March 31, 2017 is presented below: Number of Units Weighted-average grant date fair value per unit Outstanding at December 31, 2016 298,357 $ 32.81 Granted 159,462 52.11 Converted into shares of common stock (40,141 ) 26.86 Forfeited/expired (316 ) 32.81 Outstanding at March 31, 2017 417,362 $ 40.76 At March 31, 2017 , unrecognized compensation expense related to restricted stock units totaled $13.4 million and is expected to be recognized over a remaining weighted average period of 3.3 years . Restricted Stock Awards The Corporation assumed restricted stock awards in the merger with Talmer that vest upon completion of future service requirements. The fair value of these awards is equal to the market price of the Corporation's common stock at the date the awards were assumed with the portion of the fair value related to post-combination service. The Corporation recognizes stock-based compensation expense over the vesting period, using the straight-lined method, based upon the number of shares of restricted stock ultimately expected to vest. If an individual awarded restricted stock awards terminates employment prior to the end of the vesting period, the unvested portion of the stock is forfeited, with certain exceptions. The following table provides information regarding nonvested restricted stock awards: Nonvested restricted stock awards Number of Awards Weighted-average acquisition-date Nonvested at January 1, 2017 365,891 $ 46.23 Vested (61,049 ) 46.23 Forfeited (1,524 ) 46.23 Nonvested at March 31, 2017 303,318 $ 46.23 At March 31, 2017 , unrecognized compensation expense related to nonvested restricted stock awards totaled $4.8 million and is expected to be recognized over a remaining weighted average period of 1.1 years.

Pension and Other Postretiremen

Pension and Other Postretirement Benefit Plans	3 Months Ended
	Mar. 31, 2017
Compensation and Retirement Disclosure [Abstract]
Pension and Other Postretirement Benefit Plans	Pension and Other Postretirement Benefit Plans The Corporation's retirement plans include a qualified pension plan, a nonqualified pension plan, a nonqualified postretirement benefit plan, a 401(k) savings plan, and a multi-employer defined benefit plan. Qualified and Nonqualified Pension Plans and Nonqualified Postretirement Benefit Plans The components of net periodic benefit cost for the Corporation’s qualified and nonqualified pension plans and nonqualified postretirement benefit plan are as follows: Three Months Ended March 31, (Dollars in thousands) 2017 2016 Defined Benefit Pension Plans Service cost $ 233 $ 277 Interest cost 1,302 1,358 Expected return on plan assets (2,217 ) (2,141 ) Amortization of unrecognized net loss 578 572 Net periodic benefit cost (income) $ (104 ) $ 66 Postretirement Benefit Plan Service cost $ 1 $ 2 Interest cost 24 33 Amortization of prior service cost — 29 Amortization of unrecognized net gain (41 ) (24 ) Net periodic benefit cost (income) $ (16 ) $ 40 The Corporation did no t make a contribution to the pension plan during the three months ended March 31, 2017 or 2016 . The discount rate used to compute the Corporation's pension plan expense for 2017 is 4.2% . The discount rate used to compute the Corporation's nonqualified pension plan for 2017 is 3.6% . 401(k) Savings Plan 401(k) Savings Plan expense for the Corporation’s match of participants’ base compensation contributions and a 4.0% of eligible pay contribution to employees who are not grandfathered under the pension plan was $2.5 million and $1.3 million for the three months ended March 31, 2017 and 2016 , respectively. The Corporation's base compensation match equals 50.0% of the participants' elective deferrals on the first 4.0% of the participants' base compensation up to the maximum amount allowed under the Internal Revenue Code. Multi-Employer Defined Benefit Plan In conjunction with the April 1, 2015 acquisition of Monarch, the Corporation acquired a participation in the Pentegra Defined Benefit Plan for Financial Institutions (Pentegra DB Plan), a qualified defined benefit pension plan. Employee benefits for Monarch employees under the Plan were frozen effective April 1, 2004. The Pentegra DB Plan operates as a multi-employer plan for accounting purposes and as a multiple-employer plan under the Employee Retirement Income Security Act of 1974 and the Internal Revenue Code (IRC). The Pentegra DB Plan is a single plan under IRC Section 413(c) and, as a result, all of the plan's assets stand behind all of the plan's liabilities. Accordingly, contributions made by a participating employer may be used to provide benefits to participants of other participating employers. No contributions were made by the Corporation to the Pentegra DB Plan for the three months ended March 31, 2017 and 2016 .

Regulatory Capital

Regulatory Capital	3 Months Ended
	Mar. 31, 2017
Banking and Thrift [Abstract]
Regulatory Capital	Regulatory Capital Federal and state banking regulations place certain restrictions on the transfer of assets, in the form of dividends, loans, or advances, from Chemical Bank to the Corporation. As of March 31, 2017 , substantially all of the assets of Chemical Bank were restricted from transfer to the Corporation in the form of loans or advances. Dividends from the bank are the principal source of funds for the Corporation. In addition to the statutory limits, the Corporation considers the overall financial and capital position of the bank prior to making any cash dividend decisions. The Corporation and Chemical Bank are subject to various regulatory capital requirements administered by federal banking agencies. Under these capital requirements, Chemical Bank must meet specific capital guidelines that involve quantitative measures of assets and certain off-balance sheet items as calculated under regulatory accounting practices. In addition, capital amounts and classifications are subject to qualitative judgments by regulators. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Corporation’s consolidated financial statements. Management believes as of March 31, 2017 , the Corporation and Chemical Bank met all capital adequacy requirements to which they are subject. Quantitative measures established by regulation to ensure capital adequacy require minimum ratios of Tier 1 capital to average assets (Leverage Ratio) and common equity Tier 1, Tier 1 and Total capital to risk-weighted assets. These capital guidelines assign risk weights to on- and off-balance sheet items in arriving at total risk-weighted assets. Minimum capital levels are based upon the perceived risk of various asset categories and certain off-balance sheet instruments. Risk-weighted assets of the Corporation and Chemical Bank totaled $13.62 billion and $13.58 billion at March 31, 2017 , respectively, compared to $13.42 billion and $13.36 billion at December 31, 2016 , respectively. Effective January 1, 2015, the Company adopted the new Basel III regulatory capital framework as approved by federal banking agencies, which are subject to a multi-year phase-in period. The adoption of this new framework modified the calculation of the various capital ratios, added a new ratio, common equity tier 1, and revised the adequately and well capitalized thresholds. In addition, Basel III establishes a new capital conservation buffer of 2.5% of risk-weighted assets, which is phased-in over a four-year period beginning January 1, 2016. The capital conservation buffer for 2017 is 1.25% and was 0.625% for 2016. The Corporation has elected to opt-out of including capital in accumulated other comprehensive income in common equity tier 1 capital. At March 31, 2017 and December 31, 2016 , Chemical Bank's capital ratios exceeded the quantitative capital ratios required for an institution to be considered "well-capitalized." Significant factors that may affect capital adequacy include, but are not limited to, a disproportionate growth in assets versus capital and a change in mix or credit quality of assets. There are no conditions or events since that notification that management believes have changed the institutions' category. The summary below compares the actual capital amounts and ratios with the quantitative measures established by regulation to ensure capital adequacy: Actual Minimum Required for Capital Adequacy Purposes Minimum Required for Capital Adequacy Purposes Plus Capital Conservation Buffer Required to be Well Capitalized Under Prompt Corrective Action Regulations (Dollars in thousands) Capital Amount Ratio Capital Amount Ratio Capital Amount Ratio Capital Amount Ratio March 31, 2017 Total Capital to Risk-Weighted Assets Corporation $ 1,547,145 11.4 % $ 1,089,998 8.0 % $ 1,260,310 9.3 % N/A N/A Chemical Bank 1,581,814 11.7 1,086,008 8.0 1,255,696 9.3 $ 1,357,510 10.0 % Tier 1 Capital to Risk-Weighted Assets Corporation 1,445,929 10.6 817,498 6.0 987,810 7.3 N/A N/A Chemical Bank 1,496,181 11.0 814,506 6.0 984,195 7.3 1,086,008 8.0 Common Equity Tier 1 Capital to Risk-Weighted Assets Corporation 1,445,929 10.6 613,124 4.5 783,436 5.8 N/A N/A Chemical Bank 1,496,181 11.0 610,879 4.5 780,568 5.8 882,381 6.5 Leverage Ratio Corporation 1,445,929 8.9 651,811 4.0 651,811 4.0 N/A N/A Chemical Bank 1,496,181 9.2 650,356 4.0 650,356 4.0 812,945 5.0 December 31, 2016 Total Capital to Risk-Weighted Assets Corporation $ 1,543,018 11.5 % $ 1,073,431 8.0 % $ 1,157,293 8.6 % N/A N/A Chemical Bank 1,608,980 12.0 1,068,560 8.0 1,152,041 8.6 $ 1,335,700 10.0 % Tier 1 Capital to Risk-Weighted Assets Corporation 1,441,209 10.7 805,073 6.0 888,935 6.6 N/A N/A Chemical Bank 1,522,711 11.4 801,420 6.0 884,901 6.6 1,068,560 8.0 Common Equity Tier 1 Capital to Risk-Weighted Asset Corporation 1,441,209 10.7 603,805 4.5 687,667 5.1 N/A N/A Chemical Bank 1,522,711 11.4 601,065 4.5 684,546 5.1 868,205 6.5 Leverage Ratio Corporation 1,441,209 9.0 643,603 4.0 643,603 4.0 N/A N/A Chemical Bank 1,522,711 9.5 641,457 4.0 641,457 4.0 801,822 5.0 On April 26, 2017, a cash dividend on the Corporation's common stock of $0.27 per share was declared. The dividend will be paid on June 16, 2017 to shareholders of record as of June 2, 2017.

Earnings Per Common Share

Earnings Per Common Share	3 Months Ended
	Mar. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share The two-class method is used in the calculation of basic and diluted earnings per share. Under the two-class method, earnings available to common shareholders for the period are allocated between common shareholders and participating securities according to dividends declared (or accumulated) and participating rights in undistributed earnings. Average shares of common stock for diluted net income per common share include shares to be issued upon the exercise of stock options granted under the Corporation’s share-based compensation plans, restricted stock units that may be converted to stock, restricted stock awards and stock to be issued under the deferred stock compensation plan for non-employee directors. The factors used in the earnings per share computation follow: Three Months Ended March 31, (In thousands, except per share data) 2017 2016 Net income $ 47,604 $ 23,605 Net income allocated to participating securities 226 — Net income allocated to common shareholders (1) $ 47,378 $ 23,605 Weighted average common shares - issued 70,969 38,198 Average unvested restricted share awards (341 ) — Weighted average common shares outstanding - basic 70,628 38,198 Effect of dilutive securities Weighted average common stock equivalents 787 323 Weighted average common shares outstanding - diluted 71,415 38,521 EPS available to common shareholders Basic earnings per common share $ 0.67 $ 0.61 Diluted earnings per common share $ 0.67 $ 0.60 (1) Net income allocated to common shareholders for basic and diluted earnings per share may differ under the two-class method as a result of adding common share equivalents for options and warrants to dilutive shares outstanding, which alters the ratio used to allocate net income to common shareholders and participating securities for the purposes of calculating diluted earnings per share. For effect of dilutive securities, the assumed average stock valuation is $51.81 per share and $33.29 per share for the three months ended March 31, 2017 and 2016 , respectively. The average number of exercisable employee stock options outstanding that were "out-of-the-money," whereby the option exercise price per share exceeded the market price per share and, therefore, were not included in the computation of diluted earnings per common share because they would have been anti-dilutive totaled zero and 121,050 for the three months ended March 31, 2017 and 2016 , respectively.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss The following table summarizes the changes within each component of accumulated other comprehensive income (loss), net of related tax benefit/expense for the three months ended March 31, 2017 , and 2016 : (Dollars in thousands) Unrealized gains Defined Benefit Pension Plans Total For the three months ended March 31, 2017 Beginning balance $ (14,142 ) $ (25,894 ) $ (40,036 ) Other comprehensive income before reclassifications 1,780 — 1,780 Amounts reclassified from accumulated other comprehensive income (58 ) 349 291 Net current period other comprehensive income 1,722 349 2,071 Ending balance $ (12,420 ) $ (25,545 ) $ (37,965 ) For the three months ended March 31, 2016 Beginning balance $ (1,888 ) $ (27,144 ) $ (29,032 ) Other comprehensive income before reclassifications 2,729 — 2,729 Amounts reclassified from accumulated other comprehensive income (12 ) (375 ) (387 ) Net current period other comprehensive income (loss) 2,717 (375 ) 2,342 Ending balance $ 829 $ (27,519 ) $ (26,690 ) The following table summarizes the amounts reclassified out of each component of accumulated other comprehensive income (loss) for the three months ended March 31, 2017 , and 2016 : (Dollars in thousands) Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Income Statement Three Months Ended March 31, 2017 2016 Gains and losses on available-for-sale securities $ 90 $ 19 Gain on sale of investment securities (noninterest income) (32 ) (7 ) Income tax (expense)/benefit $ 58 $ 12 Net Income Amortization of defined benefit pension plan items $ 537 $ 577 Salaries, wages and employee benefits (operating expenses) (188 ) (202 ) Income tax (expense)/benefit $ 349 $ 375 Net Income

Basis of Presentation and Sig27

Basis of Presentation and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations Chemical Financial Corporation ("Corporation" or "Chemical") operates in a single operating segment — commercial banking. The Corporation is a financial holding company, headquartered in Midland, Michigan, that operates through one commercial bank, Chemical Bank. Chemical Bank operates within Michigan, Ohio and Indiana as a state-chartered commercial bank. Chemical Bank operates through an internal organizational structure of seven regional banking units and offers a full range of traditional banking and fiduciary products and services to the residents and business customers in the bank’s geographical market areas. The products and services offered by the regional banking units, through branch banking offices, are generally consistent throughout the Corporation, as is the pricing of those products and services. The marketing of products and services throughout the Corporation’s regional banking units is generally uniform, as many of the markets served by the regional banking units overlap. The distribution of products and services is uniform throughout the Corporation’s regional banking units and is achieved primarily through retail branch banking offices, automated teller machines and electronically accessed banking products. The Corporation’s primary sources of revenue are interest from its loan products and investment securities, service charges and fees from customer deposit accounts, wealth management revenue and mortgage banking revenue.
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The accompanying unaudited consolidated financial statements of the Corporation and its subsidiaries have been prepared in accordance with United States ("U.S.") generally accepted accounting principles ("GAAP") for interim financial information and with instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, the interim consolidated financial statements do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Corporation’s consolidated financial statements and footnotes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2016. In the opinion of management, the accompanying unaudited interim consolidated financial statements contain all adjustments believed necessary to present fairly the financial condition and results of operations of the Corporation for the periods presented. Operating results for the three months ended March 31, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 .
Use of Estimates	Use of Estimates Management makes estimates and assumptions that affect the amounts reported in the Consolidated Financial Statements and accompanying footnotes. Estimates that are particularly susceptible to significant change include the determination of the allowance for loan losses, expected cash flows from acquired loans, fair value amounts related to business combinations, income taxes, goodwill impairment and those assets that require fair value measurement. Actual results could differ from these estimates.
Reclassifications	Reclassifications Certain amounts appearing in the consolidated financial statements and notes thereto for prior periods have been reclassified to conform with the current presentation. The reclassification had no effect on net income or shareholders’ equity as previously reported.
Loan Servicing Rights	Loan Servicing Rights Effective January 1, 2017, the Corporation elected to account for all loan servicing rights ("LSRs") previously accounted for under the lower of cost or fair value method under the fair value method. The guidance in ASC Subtopic 860-50, "Transfers and Servicing-Servicing Assets and Liabilities" provides that an entity may make an irrevocable decision to subsequently measure a class of servicing assets and servicing liabilities at fair value at the beginning of any fiscal year. The guidance allows for the Corporation to apply this election prospectively to all new and existing servicing assets and servicing liabilities. Management believes this election will provide more comparable results to peers as many of those within our industry group account for loans servicing rights under the fair value method. The change in accounting policy in the first quarter of 2017 results in a cumulative adjustment to increase retained earnings in the amount of $3.7 million , net of taxes.
Investments in Qualified Affordable Housing Projects, Federal Historic Projects and New Market Tax Credits	Investments in Qualified Affordable Housing Projects, Federal Historic Projects and New Market Tax Credits The Corporation invests in qualified affordable housing projects, federal historic projects, and new market projects for the purpose of community reinvestment and obtaining tax credits. Return on the Corporation's investment in these projects comes in the form of the tax credits and tax losses that pass through to the Corporation. The carrying value of the investments are reflected in "Interest receivable and other assets" on the Consolidated Statements of Financial Position. The Corporation utilizes the proportional amortization method to account for investments in qualified affordable housing projects and the equity method to account for investments in other tax credit projects. Under the proportional amortization method, the Corporation amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits. The Corporation recognized additional income tax expense attributable to the amortization of investments in qualified affordable housing projects of $0.8 million and $0.6 million during the three months ended March 31, 2017 and 2016, respectively. The Corporation's remaining investment in qualified affordable housing projects accounted for under the proportional amortization method totaled $31.8 million at March 31, 2017 and $29.5 million at December 31, 2016 . Under the equity method, the Corporation's share of the earnings or losses are included in "Other operating expenses" on the Consolidated Statements of Income. The Corporation's remaining investment in new market projects accounted for under the equity method totaled $10.7 million and $10.9 million at March 31, 2017 and December 31, 2016 , respectively. The Corporation's unfunded equity contributions relating to investments in qualified affordable housing projects, federal historic tax projects and new market projects is recorded in "Interest payable and other liabilities" on the Consolidated Statements of Financial Position. The Corporation's remaining unfunded equity contributions totaled $18.5 million and $16.0 million at March 31, 2017 and December 31, 2016 , respectively. Management analyzes these investments for potential impairment when events or changes in circumstances indicate that it is more-likely-than-not that the carrying amount of the investment will not be realized. An impairment loss is measured as the amount by which the carrying amount of an investment exceeds its fair value. There were no impairment losses recognized as of March 31, 2017 or December 31, 2016 . The Corporation consolidates variable interest entities ("VIEs") in which it is the primary beneficiary. In general, a VIE is an entity that either (i) has an insufficient amount of equity to carry out its principal activities without additional subordinated financial support, (ii) has a group of equity owners that are unable to make significant decisions about its activities or (iii) has a group of equity owners that do not have the obligation to absorb losses or the right to receive returns as generated by its operations. If any of these characteristics are present, the entity is subject to a variable interests consolidation model, and consolidation is based on variable interests, not on ownership of the entity's outstanding voting stock. Variable interests are defined as contractual, ownership, or other monetary interests in an entity that change with fluctuations in the entity's net asset value. The primary beneficiary consolidates the VIE. The primary beneficiary is defined as the enterprise that has the power to direct the activities and absorb losses or the right to receive benefits. The Corporation is a significant limited partner in the qualified affo rdable housing, federal historic and new market projects it has invested in . These projects meet the definition of VIEs. However, the Corporation is not the primary beneficiary of any of the VIEs in which it holds a limited partnership interest; therefore, the VIEs are not consolidated in the Corporation's consolidated financial statements.

Mergers and Acquisitions (Table

Mergers and Acquisitions (Tables)	3 Months Ended
	Mar. 31, 2017
Business Combinations [Abstract]
Summary of assets acquired and liabilities assumed	The following allocation is based on the information that was available to make preliminary estimates of the fair value and may change as additional information becomes available and additional analyses are completed. While the Corporation believes that information provided a reasonable basis for estimating the fair values, it expects that it could obtain additional information and evidence during the measurement period that may result in changes to the estimated fair value amounts. This measurement period ends on the earlier of one year after the merger date or the date we receive the information about the facts and circumstances that existed at the merger date. Subsequent adjustments, if necessary, will be reflected in future filings. These refinements include: (1) changes in the estimated fair value of loans acquired: (2) changes in the estimated fair value of intangible assets acquired: (3) changes in deferred tax assets related to fair value estimates and a change in the expected realization of items considered to be net operating loss carry forwards and (4) a change in the goodwill caused by the net effect of these adjustments. (Dollars in thousands) Consideration paid: Stock $ 1,504,811 Cash 107,638 Total consideration 1,612,449 Fair value of identifiable assets acquired: Cash and cash equivalents 433,352 Investment securities: Available-for-sale 808,894 Held-to-maturity 1,657 Loans held-for-sale 244,916 Loans 4,882,402 Premises and equipment 38,793 Loan servicing rights 42,462 Other intangible assets 19,088 Interest receivable and other assets 395,119 Total identifiable assets acquired $ 6,866,683 Fair value of liabilities assumed: Noninterest-bearing deposits 1,236,902 Interest-bearing deposits 4,057,716 Interest payable and other liabilities 99,482 Securities sold under agreements to repurchase with customers 19,704 Short-term borrowings 387,500 Long-term borrowings 299,597 Total liabilities assumed $ 6,100,901 Fair value of net identifiable assets acquired $ 765,782 Goodwill resulting from acquisition $ 846,667
Information regarding acquired loans accounted for under ASC 310-30	Information regarding loans accounted for under ASC 310-30 at the merger date is as follows: (Dollars in thousands) Accounted for under ASC 310-30: Contractual cash flows $ 5,968,488 Contractual cash flows not expected to be collected (nonaccretable difference) 223,959 Expected cash flows 5,744,529 Interest component of expected cash flows (accretable yield) 862,127 Fair value at acquisition $ 4,882,402
Pro forma financial information	The following unaudited pro forma financial information presents the consolidated results of operation of the Corporation and Talmer as if the merger had occurred as of January 1, 2016. The unaudited pro forma combined results of operations are presented solely for information purposes and are not intended to represent or be indicative of the consolidated results of operations that Chemical would have reported had these transactions been completed as of the dates and for the periods presented, nor are they necessarily indicative of future results. In particular, no adjustments have been made to eliminate the amount of Talmer's provision for loan losses incurred prior to the acquisition date that would not have been necessary had the acquired loans been recorded at fair value as of the beginning of each period indicated. In accordance with Article 11 of SEC Regulation S-X, transaction costs directly attributable to the acquisitions have been excluded. For the three months ended, (Dollars in thousands) March 31, 2017 (1) March 31, 2016 Net interest and other income $ 168,107 $ 157,932 Net Income 47,604 39,028 Earnings per share: Basic $ 0.67 $ 0.56 Diluted 0.67 0.55 (1) As the business combination was effective August 31, 2016, there were no proforma adjustments for the three months ended March 31, 2017.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Summary of assets measured at fair value on a recurring basis	For assets and liabilities measured at fair value on a recurring basis, quantitative disclosures about the fair value measurements for each major category of assets and liabilities follow: (Dollars in thousands) Quoted Prices In Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total March 31, 2017 Investment securities – available-for-sale: U.S. Treasury securities $ 5,793 $ — $ — $ 5,793 Government sponsored agencies — 224,339 — 224,339 State and political subdivisions — 300,409 — 300,409 Residential mortgage-backed securities — 256,544 — 256,544 Collateralized mortgage obligations — 367,321 — 367,321 Corporate bonds — 89,253 — 89,253 Preferred stock and trust preferred securities — 32,187 — 32,187 Total investment securities – available-for-sale 5,793 1,270,053 — 1,275,846 Loans held-for-sale — 39,123 — 39,123 Loan servicing rights — — 64,604 64,604 Derivative assets: Customer-initiated derivatives — 6,377 — 6,377 Interest rate lock commitments — 2,178 — 2,178 Power Equity CD — 2,234 — 2,234 Total derivatives — 10,789 — 10,789 Total assets at fair value $ 5,793 $ 1,319,965 $ 64,604 $ 1,390,362 Derivative liabilities: Customer-initiated derivatives — 6,342 — 6,342 Forward contracts related to mortgage loans to be delivered for sale — 342 — 342 Power Equity CD — 2,234 — 2,234 Total derivatives — 8,918 — 8,918 Total liabilities at fair value $ — $ 8,918 $ — $ 8,918 December 31, 2016 Investment securities – available-for-sale: U.S. Treasury securities $ 5,793 $ — $ — $ 5,793 Government sponsored agencies — 215,011 — 215,011 State and political subdivisions — 300,088 — 300,088 Residential mortgage-backed securities — 272,282 — 272,282 Collateralized mortgage obligations — 320,025 — 320,025 Corporate bonds — 89,474 — 89,474 Preferred stock and trust preferred securities — 32,291 — 32,291 Total investment securities – available-for-sale 5,793 1,229,171 — 1,234,964 Loans held-for-sale — 81,830 — 81,830 Loan servicing rights — — 48,085 48,085 Derivative assets: Customer-initiated derivatives — 4,406 — 4,406 Forward contracts related to mortgage loans to be delivered for sale — 635 — 635 Interest rate lock commitments — 956 — 956 Power Equity CD — 2,218 — 2,218 Total derivatives — 8,215 — 8,215 Total assets at fair value $ 5,793 $ 1,319,216 $ 48,085 $ 1,373,094 Derivative liabilities: Customer-initiated derivatives — 4,141 — 4,141 Power Equity CD — 2,218 — 2,218 Total derivatives — 6,359 — 6,359 Total liabilities at fair value $ — $ 6,359 $ — $ 6,359
Summary of changes in Level 3 assets measured at fair value on a recurring basis	The following table summarizes the changes in Level 3 assets measured at fair value on a recurring basis. Three months ended March 31, 2017 (Dollars in thousands) Loan servicing rights Balance, beginning of period $ 48,085 Transfer in based on new accounting policy election (1) 15,891 Gains (losses): Recorded in earnings (realized): Recorded in “Mortgage banking revenue” (1,125 ) New originations 1,753 Balance, end of period $ 64,604 (1) Refer to Note 1 for further details.
Schedule of aggregate fair value contractual balance and gain (loss) for loans held-for-sale	The aggregate fair value, contractual balance (including accrued interest), and gain or loss for loans held-for-sale carried at fair value was as follows: (Dollars in thousands) March 31, 2017 December 31, 2016 Aggregate fair value $ 39,123 $ 81,830 Contractual balance 37,701 81,009 Unrealized gain (loss) 1,422 821
Amount of gains (losses) from loans held for sale included in the Consolidated Statements of Income	The total amount of gains (losses) from loans held-for-sale included in the Consolidated Statements of Income were as follows: For the three months ended (Dollars in thousands) 2017 2016 Interest income (1) $ 551 $ 19 Change in fair value (2) 601 — Total included in earnings $ 1,152 $ 19 (1) Included in "Interest and fees on loans" in the Consolidated Statements of Income. (2) Included in "Mortgage banking revenue" in the Consolidated Statements of Income.
Summary of assets measured at fair value on a nonrecurring basis	For assets measured at fair value on a nonrecurring basis, quantitative disclosures about fair value measurements for each major category of assets follows: (Dollars in thousands) Quoted Prices In Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total March 31, 2017 Impaired originated loans $ — $ — $ 63,180 $ 63,180 Other real estate/repossessed assets — — 2,240 2,240 Total $ — $ — $ 65,420 $ 65,420 December 31, 2016 Impaired originated loans $ — $ — $ 62,184 $ 62,184 Other real estate/repossessed assets — — 1,386 1,386 Loan servicing rights — — 2 2 Total $ — $ — $ 63,572 $ 63,572
Additional information about significant unobservable inputs used in the fair value measurement of financial assets	The following table presents additional information about the significant unobservable inputs used in the fair value measurement of financial assets measured on a nonrecurring basis that were categorized within the Level 3 of the fair value hierarchy: (Dollars in thousands) Fair Value at March 31, 2017 Valuation Technique Significant Unobservable Inputs Range Impaired originated loans $ 63,180 Appraisal of collateral Discount for type of collateral and age of appraisal 10%-25% Other real estate/repossessed assets 2,240 Appraisal of property Discount for type of property and age of appraisal 10%-25%
Summary of carrying amounts and estimated fair values of the financial instruments	A summary of carrying amounts and estimated fair values of the Corporation’s financial instruments not recorded at fair value in their entirety on a recurring basis on the Consolidated Statements of Financial Position was as follows: Level in Fair Value Measurement Hierarchy March 31, 2017 December 31, 2016 (Dollars in thousands) Carrying Amount Fair Value Carrying Amount Fair Value Financial assets: Cash and cash equivalents Level 1 $ 441,780 $ 441,780 $ 474,402 $ 474,402 Investment securities: Held-to-maturity Level 2 646,692 639,450 622,927 608,221 Held-to-maturity Level 3 500 350 500 310 Nonmarketable equity securities Level 2 129,939 129,939 97,350 97,350 Net loans (1) Level 3 13,194,618 13,347,793 12,912,511 13,069,315 Interest receivable Level 2 45,863 45,863 42,235 42,235 Financial liabilities: Deposits: Deposits without defined maturities Level 2 $ 10,213,518 $ 10,213,518 $ 9,862,755 $ 9,862,755 Time deposits Level 2 2,918,829 2,919,153 3,010,367 3,010,048 Total deposits 13,132,347 13,132,671 12,873,122 12,872,803 Interest payable Level 2 5,225 5,225 5,415 5,415 Securities sold under agreements to repurchase with customers Level 2 398,910 398,910 343,047 343,047 Short-term borrowings Level 2 900,000 899,777 825,000 825,000 Long-term borrowings Level 2 490,876 486,161 597,847 591,227 (1) Included $63.2 million and $62.2 million of impaired loans recorded at fair value on a nonrecurring basis at March 31, 2017 and December 31, 2016 , respectively.

Investment Securities (Tables)

Investment Securities (Tables)	3 Months Ended
	Mar. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities	The following is a summary of the amortized cost and fair value of investment securities available-for-sale and investment securities held-to-maturity at March 31, 2017 and December 31, 2016 : Investment Securities Available-for-Sale (Dollars in thousands) Amortized Cost Unrealized Gains Unrealized Losses Fair Value March 31, 2017 U.S. Treasury securities $ 5,792 $ 1 $ — $ 5,793 Government sponsored agencies 225,993 153 1,807 224,339 State and political subdivisions 309,518 140 9,249 300,409 Residential mortgage-backed securities 260,703 45 4,204 256,544 Collateralized mortgage obligations 371,084 75 3,838 367,321 Corporate bonds 90,438 27 1,212 89,253 Preferred stock and trust preferred securities 31,426 1,042 281 32,187 Total $ 1,294,954 $ 1,483 $ 20,591 $ 1,275,846 December 31, 2016 U.S. Treasury securities $ 5,788 $ 5 $ — $ 5,793 Government sponsored agencies 216,890 189 2,068 215,011 State and political subdivisions 311,704 163 11,779 300,088 Residential mortgage-backed securities 276,162 112 3,992 272,282 Collateralized mortgage obligations 323,965 63 4,003 320,025 Corporate bonds 90,859 16 1,401 89,474 Preferred stock and trust preferred securities 31,353 1,018 80 32,291 Total $ 1,256,721 $ 1,566 $ 23,323 $ 1,234,964
Held-to-maturity Securities	Investment Securities Held-to-Maturity (Dollars in thousands) Amortized Cost Unrealized Gains Unrealized Losses Fair Value March 31, 2017 State and political subdivisions $ 646,692 $ 3,830 $ 11,072 $ 639,450 Trust preferred securities 500 — 150 350 Total $ 647,192 $ 3,830 $ 11,222 $ 639,800 December 31, 2016 State and political subdivisions $ 622,927 $ 2,648 $ 17,354 $ 608,221 Trust preferred securities 500 — 190 310 Total $ 623,427 $ 2,648 $ 17,544 $ 608,531
Proceeds from sales of securities and the associated gains and losses recorded in earnings	Proceeds from sales of securities and the associated gains and losses recorded in earnings are listed below: For the three months ended March 31, (Dollars in thousands) 2017 2016 Proceeds $ — $ 644 Gross gains 90 19
Amortized cost and fair value of debt securities by contractual maturity	The following is a summary of the amortized cost and fair value of investment securities at March 31, 2017 , by maturity, for both available-for-sale and held-to-maturity investment securities. The maturities of residential mortgage-backed securities and collateralized mortgage obligations are based on scheduled principal payments. The maturities of all other debt securities are based on final contractual maturity. March 31, 2017 (Dollars in thousands) Amortized Cost Fair Value Investment Securities Available-for-Sale: Due in one year or less $ 248,015 $ 246,683 Due after one year through five years 529,893 524,707 Due after five years through ten years 347,825 340,248 Due after ten years 167,832 162,405 Preferred stock 1,389 1,803 Total $ 1,294,954 $ 1,275,846 Investment Securities Held-to-Maturity: Due in one year or less $ 70,242 $ 70,210 Due after one year through five years 271,055 268,753 Due after five years through ten years 146,712 144,004 Due after ten years 159,183 156,833 Total $ 647,192 $ 639,800
Summary of continuous unrealized loss position of securities	The following schedule summarizes information for both available-for-sale and held-to-maturity investment securities with gross unrealized losses at March 31, 2017 and December 31, 2016 , aggregated by category and length of time that individual securities have been in a continuous unrealized loss position. As of March 31, 2017 , the Corporation’s securities portfolio consisted of 2,309 securities, 1,418 of which were in an unrealized loss position. Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses March 31, 2017 Government sponsored agencies $ 108,300 $ 1,445 $ 11,203 $ 362 $ 119,503 $ 1,807 State and political subdivisions 705,870 19,603 26,084 718 731,954 20,321 Residential mortgage-backed securities 248,111 4,204 — — 248,111 4,204 Collateralized mortgage obligations 311,566 3,626 12,528 212 324,094 3,838 Corporate bonds 78,815 1,211 1,499 1 80,314 1,212 Trust preferred securities 10,511 281 350 150 10,861 431 Total $ 1,463,173 $ 30,370 $ 51,664 $ 1,443 $ 1,514,837 $ 31,813 December 31, 2016 Government sponsored agencies $ 105,702 $ 1,707 $ 15,023 $ 361 $ 120,725 $ 2,068 State and political subdivisions 758,063 28,158 26,810 975 784,873 29,133 Residential mortgage-backed securities 244,239 3,992 — — 244,239 3,992 Collateralized mortgage obligations 279,001 3,778 14,754 225 293,755 4,003 Corporate bonds 80,536 1,401 — — 80,536 1,401 Trust preferred securities 10,699 80 310 190 11,009 270 Total $ 1,478,240 $ 39,116 $ 56,897 $ 1,751 $ 1,535,137 $ 40,867

Loans (Tables)

Loans (Tables)	3 Months Ended
	Mar. 31, 2017
Receivables [Abstract]
Summary of loans under portfolio	A summary of the Corporation's loans follows: (Dollars in thousands) Originated Acquired (1) Total Loans March 31, 2017 Commercial loan portfolio: Commercial $ 1,989,609 $ 1,263,999 $ 3,253,608 Commercial real estate 2,114,540 1,983,231 4,097,771 Real estate construction and land development 327,740 126,071 453,811 Subtotal 4,431,889 3,373,301 7,805,190 Consumer loan portfolio: Residential mortgage 1,594,376 1,539,089 3,133,465 Consumer installment 1,342,063 138,994 1,481,057 Home equity 591,441 262,239 853,680 Subtotal 3,527,880 1,940,322 5,468,202 Total loans $ 7,959,769 $ 5,313,623 $ 13,273,392 (2 ) December 31, 2016 Commercial loan portfolio: Commercial $ 1,901,526 $ 1,315,774 $ 3,217,300 Commercial real estate 1,921,799 2,051,341 3,973,140 Real estate construction and land development 281,724 122,048 403,772 Subtotal 4,105,049 3,489,163 7,594,212 Consumer loan portfolio: Residential mortgage 1,475,342 1,611,132 3,086,474 Consumer installment 1,282,588 151,296 1,433,884 Home equity 595,422 280,787 876,209 Subtotal 3,353,352 2,043,215 5,396,567 Total loans $ 7,458,401 $ 5,532,378 $ 12,990,779 (2 ) (1) Acquired loans are accounted for under ASC 310-30. (2) Reported net of deferred costs totaling $15.0 million and $14.8 million at March 31, 2017 and December 31, 2016 , respectively.
Schedule of activity for accretable yield	Activity for the accretable yield, which includes contractually due interest for acquired loans that have been renewed or extended since the date of acquisition and continue to be accounted for in loan pools in accordance with ASC 310-30, follows: (Dollars in thousands) Talmer Lake Michigan Monarch North-western OAK Total Three Months Ended March 31, 2017 Balance at beginning of period $ 798,210 $ 121,416 $ 27,182 $ 69,847 $ 23,316 $ 1,039,971 Additions (reductions) (1) — (939 ) 54 (1,058 ) 1,428 (515 ) Accretion recognized in interest income (44,571 ) (7,266 ) (1,181 ) (3,892 ) (3,277 ) (60,187 ) Reclassification from nonaccretable difference 21,139 — — — — 21,139 Balance at end of period $ 774,778 $ 113,211 $ 26,055 $ 64,897 $ 21,467 $ 1,000,408 Three Months Ended March 31, 2016 Balance at beginning of period $ — $ 152,999 $ 34,558 $ 82,623 $ 28,077 $ 298,257 Additions (reductions) (1) — (6,071 ) 128 (2,254 ) 1,516 (6,681 ) Accretion recognized in interest income — (8,953 ) (1,451 ) (4,001 ) (2,557 ) (16,962 ) Balance at end of period $ — $ 137,975 $ 33,235 $ 76,368 $ 27,036 $ 274,614 (1) Represents additions of estimated contractual interest expected to be collected from acquired loans being renewed or extended, less reductions in contractual interest resulting from the early payoff of acquired loans.
Recorded investment of loans in the commercial loan portfolio by risk rating categories	The following schedule presents the recorded investment of loans in the commercial loan portfolio by credit risk categories at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Pass Special Mention Substandard Doubtful Total March 31, 2017 Originated Portfolio: Commercial $ 1,902,773 $ 34,018 $ 52,818 $ — $ 1,989,609 Commercial real estate 2,040,155 37,528 36,856 1 2,114,540 Real estate construction and land development 326,942 719 79 — 327,740 Subtotal 4,269,870 72,265 89,753 1 4,431,889 Acquired Portfolio: Commercial 1,171,260 39,079 53,625 35 1,263,999 Commercial real estate 1,841,116 52,038 89,912 165 1,983,231 Real estate construction and land development 122,593 1,887 1,591 — 126,071 Subtotal 3,134,969 93,004 145,128 200 3,373,301 Total $ 7,404,839 $ 165,269 $ 234,881 $ 201 $ 7,805,190 December 31, 2016 Originated Portfolio: Commercial $ 1,803,750 $ 44,809 $ 51,898 $ 1,069 $ 1,901,526 Commercial real estate 1,849,315 36,981 35,502 1 1,921,799 Real estate construction and land development 280,968 157 599 — 281,724 Subtotal 3,934,033 81,947 87,999 1,070 4,105,049 Acquired Portfolio: Commercial 1,218,848 46,643 50,283 — 1,315,774 Commercial real estate 1,897,011 61,441 92,636 253 2,051,341 Real estate construction and land development 117,505 1,982 2,561 — 122,048 Subtotal 3,233,364 110,066 145,480 253 3,489,163 Total $ 7,167,397 $ 192,013 $ 233,479 $ 1,323 $ 7,594,212
Recorded investment of loans in the consumer loan portfolio based on the credit risk profile of loans in a performing and nonperforming status	The following schedule presents the recorded investment of loans in the consumer loan portfolio based on loans in a performing status and loans in a nonperforming status at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Residential Mortgage Consumer Installment Home Equity Total Consumer March 31, 2017 Originated Loans: Performing $ 1,587,627 $ 1,341,308 $ 588,728 $ 3,517,663 Nonperforming 6,749 755 2,713 10,217 Subtotal 1,594,376 1,342,063 591,441 3,527,880 Acquired Loans 1,539,089 138,994 262,239 1,940,322 Total $ 3,133,465 $ 1,481,057 $ 853,680 $ 5,468,202 December 31, 2016 Originated Loans: Performing $ 1,468,373 $ 1,281,709 $ 592,071 $ 3,342,153 Nonperforming 6,969 879 3,351 11,199 Subtotal 1,475,342 1,282,588 595,422 3,353,352 Acquired Loans 1,611,132 151,296 280,787 2,043,215 Total $ 3,086,474 $ 1,433,884 $ 876,209 $ 5,396,567
Summary of nonperforming loans	A summary of nonperforming loans follows: (Dollars in thousands) March 31, December 31, Nonperforming assets Nonaccrual loans: Commercial $ 16,717 $ 13,178 Commercial real estate 20,828 19,877 Real estate construction and land development 79 80 Residential mortgage 6,749 6,969 Consumer installment 755 879 Home equity 2,713 3,351 Total nonaccrual loans 47,841 44,334 Other real estate owned and repossessed assets 16,395 17,187 Total nonperforming assets $ 64,236 $ 61,521 Accruing loans contractually past due 90 days or more as to interest or principal payments, excluding acquired loans accounted for under ASC 310-30 Commercial 1,823 11 Commercial real estate 700 277 Home equity 1,169 995 Total accruing loans contractually past due 90 days or more as to interest or principal payments, excluding acquired loans accounted for under ASC 310-30 $ 3,692 $ 1,283
Schedule representing the aging status of the recorded investment in loans by classes	Loan delinquency, excluding acquired loans accounted for under ASC 310-30, was as follows: (Dollars in thousands) 30-59 days past due 60-89 days past due 90 days or more past due Total past due Current Total loans 90 days or more past due and still accruing March 31, 2017 Originated Portfolio: Commercial $ 10,603 $ 9,411 $ 8,661 $ 28,675 $ 1,960,934 $ 1,989,609 $ 1,823 Commercial real estate 9,712 2,625 6,016 18,353 2,096,187 2,114,540 700 Real estate construction and land development 3,495 1,770 — 5,265 322,475 327,740 — Residential mortgage 12,918 731 941 14,590 1,579,786 1,594,376 — Consumer installment 2,805 275 235 3,315 1,338,748 1,342,063 — Home equity 3,976 552 1,536 6,064 585,377 591,441 1,169 Total $ 43,509 $ 15,364 $ 17,389 $ 76,262 $ 7,883,507 $ 7,959,769 $ 3,692 December 31, 2016 Originated Portfolio: Commercial $ 10,421 $ 4,842 $ 3,641 $ 18,904 $ 1,882,622 $ 1,901,526 $ 11 Commercial real estate 6,551 1,589 5,165 13,305 1,908,494 1,921,799 277 Real estate construction and land development 2,721 499 — 3,220 278,504 281,724 — Residential mortgage 3,147 62 1,752 4,961 1,470,381 1,475,342 — Consumer installment 3,991 675 238 4,904 1,277,684 1,282,588 — Home equity 3,097 893 2,349 6,339 589,083 595,422 995 Total $ 29,928 $ 8,560 $ 13,145 $ 51,633 $ 7,406,768 $ 7,458,401 $ 1,283
Schedule of Impaired loans by classes	The following schedules present impaired loans by classes of loans at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Recorded Investment Unpaid Principal Balance Related Valuation Allowance March 31, 2017 Impaired loans with a valuation allowance: Commercial $ 26,201 $ 29,804 $ 2,468 Commercial real estate 20,416 25,875 1,251 Real estate construction and land development 164 164 2 Residential mortgage 16,944 16,944 1,162 Consumer installment 799 799 102 Home equity 4,296 4,296 655 Subtotal 68,820 77,882 5,640 Impaired loans with no related valuation allowance: Commercial 9,028 14,910 — Commercial real estate 22,791 26,569 — Real estate construction and land development 79 79 — Residential mortgage 3,607 3,607 — Consumer installment 62 62 — Home equity 512 512 — Subtotal 36,079 45,739 — Total impaired loans: Commercial 35,229 44,714 2,468 Commercial real estate 43,207 52,444 1,251 Real estate construction and land development 243 243 2 Residential mortgage 20,551 20,551 1,162 Consumer installment 861 861 102 Home equity 4,808 4,808 655 Total $ 104,899 $ 123,621 $ 5,640 December 31, 2016 Impaired loans with a valuation allowance: Commercial $ 28,925 $ 33,209 $ 3,128 Commercial real estate 21,318 27,558 2,102 Real estate construction and land development 177 177 4 Residential mortgage 20,864 20,864 3,528 Consumer installment 879 879 240 Home equity 2,577 2,577 390 Subtotal 74,740 85,264 9,392 Impaired loans with no related valuation allowance: Commercial 7,435 11,153 — Commercial real estate 20,588 23,535 — Real estate construction and land development 80 80 — Residential mortgage 3,252 3,252 — Home equity 774 774 — Subtotal 32,129 38,794 — Total impaired loans: Commercial 36,360 44,362 3,128 Commercial real estate 41,906 51,093 2,102 Real estate construction and land development 257 257 4 Residential mortgage 24,116 24,116 3,528 Consumer installment 879 879 240 Home equity 3,351 3,351 390 Total $ 106,869 $ 124,058 $ 9,392
Schedule presents information related to impaired loans	The following schedule presents additional information regarding impaired loans by classes of loans segregated by those requiring a valuation allowance and those not requiring a valuation allowance for the three months ended March 31, 2017 and 2016 , and the respective interest income amounts recognized: Three Months Ended March 31, 2017 Three Months Ended March 31, 2016 (Dollars in thousands) Average recorded investment Interest income recognized while on impaired status Average recorded investment Interest income recognized while on impaired status Impaired loans with a valuation allowance: Commercial $ 25,712 $ — $ 10,551 $ — Commercial real estate 20,035 — 7,592 — Real estate construction and land development 161 — — — Residential mortgage 17,398 264 20,988 333 Consumer installment 780 — — — Home equity 4,071 — — — Subtotal $ 68,157 $ 264 $ 39,131 $ 333 Impaired loans with no related valuation allowance: Commercial $ 9,297 $ 255 $ 31,404 $ 277 Commercial real estate 23,473 306 45,737 380 Real estate construction and land development 81 2 918 6 Residential mortgage 3,808 — 5,149 — Consumer installment 215 — 340 — Home equity 880 — 2,388 — Subtotal $ 37,754 $ 563 $ 85,936 $ 663 Total impaired loans: Commercial $ 35,009 $ 255 $ 41,955 $ 277 Commercial real estate 43,508 306 53,329 380 Real estate construction and land development 242 2 918 6 Residential mortgage 21,206 264 26,137 333 Consumer installment 995 — 340 — Home equity 4,951 — 2,388 — Total $ 105,911 $ 827 $ 125,067 $ 996
Schedule providing information on TDRs	The following tables present the recorded investment of loans modified into TDRs during the three months ended March 31, 2017 and 2016 by type of concession granted. In cases where more than one type of concession was granted, the loans were categorized based on the most significant concession. Concession type (Dollars in thousands) Principal Interest Forbearance Total Pre-modification recorded investment Post-modification recorded investment For the three months ended March 31, 2017 Commercial loan portfolio: Commercial $ 50 $ 1,101 $ 579 5 $ 1,739 $ 1,730 Commercial real estate 447 75 — 3 522 522 Subtotal 497 1,176 579 8 2,261 2,252 Consumer loan portfolio: Residential mortgage 98 — — 1 98 98 Consumer installment 10 — — 2 11 10 Home equity 111 — — 1 165 111 Subtotal 219 — — 4 274 219 Total loans $ 716 $ 1,176 $ 579 12 $ 2,535 $ 2,471 For the three months ended March 31, 2016 Commercial loan portfolio: Commercial $ 3,832 $ — $ — 7 $ 3,832 $ 3,832 Commercial real estate 987 — — 4 987 987 Subtotal 4,819 — — 11 4,819 4,819 Consumer loan portfolio: Residential mortgage 105 — — 1 105 105 Consumer installment 33 — — 4 33 33 Home equity 29 37 — 2 66 66 Subtotal 167 37 — 7 204 204 Total loans $ 4,986 $ 37 $ — 18 $ 5,023 $ 5,023 The following schedule presents the Corporation's TDRs at March 31, 2017 and December 31, 2016 : (Dollars in thousands) Accruing TDRs Nonaccrual TDRs Total March 31, 2017 Commercial loan portfolio $ 41,055 $ 23,842 $ 64,897 Consumer loan portfolio 16,003 4,100 20,103 Total $ 57,058 $ 27,942 $ 85,000 December 31, 2016 Commercial loan portfolio $ 45,388 $ 25,397 $ 70,785 Consumer loan portfolio 17,147 5,134 22,281 Total $ 62,535 $ 30,531 $ 93,066
Troubled debt restructurings on financing receivables with defaults payment	The following schedule includes TDRs for which there was a payment default during the three months ended March 31, 2017 and 2016 , whereby the borrower was past due with respect to principal and/or interest for 90 days or more, and the loan became a TDR during the twelve-month period prior to the default: Three Months Ended March 31, 2017 Three Months Ended March 31, 2016 (Dollars in thousands) Number of loans Principal balance Number of loans Principal balance Commercial loan portfolio: Commercial 3 $ 620 — $ — Commercial real estate — — 1 933 Subtotal - Commercial loan portfolio 3 620 1 933 Consumer loan portfolio (residential mortgage) 2 105 1 — Total 5 $ 725 2 $ 933
Schedule of allowance and recorded investment related to financing receivables segregated by portfolio segment	The following schedule presents, by loan portfolio segment, the changes in the allowance for the three months ended March 31, 2017 and 2016 , and details regarding the balance in the allowance and the recorded investment in loans at March 31, 2017 by impairment evaluation method. (Dollars in thousands) Commercial Loan Portfolio Consumer Loan Portfolio Total Changes in allowance for loan losses for the three months ended March 31, 2017: Beginning balance $ 51,201 $ 27,067 $ 78,268 Provision for loan losses 4,392 (342 ) 4,050 Charge-offs (2,691 ) (2,883 ) (5,574 ) Recoveries 1,413 617 2,030 Ending balance $ 54,315 $ 24,459 $ 78,774 Changes in allowance for loan losses for the three months ended March 31, 2016: Beginning balance $ 47,234 $ 26,094 $ 73,328 Provision for loan losses 1,000 500 1,500 Charge-offs (3,896 ) (1,562 ) (5,458 ) Recoveries 330 618 948 Ending balance $ 44,668 $ 25,650 $ 70,318 Allowance for loan losses balance at March 31, 2017 attributable to: Loans individually evaluated for impairment $ 3,721 $ 1,919 $ 5,640 Loans collectively evaluated for impairment 50,594 22,540 73,134 Loans acquired with deteriorated credit quality — — — Total $ 54,315 $ 24,459 $ 78,774 Recorded investment (loan balance) at March 31, 2017: Loans individually evaluated for impairment $ 78,679 $ 26,220 $ 104,899 Loans collectively evaluated for impairment 4,353,210 3,501,660 7,854,870 Loans acquired with deteriorated credit quality 3,373,301 1,940,322 5,313,623 Total $ 7,805,190 $ 5,468,202 $ 13,273,392 The following schedule presents, by loan portfolio segment, details regarding the balance in the allowance and the recorded investment in loans at December 31, 2016 by impairment evaluation method. (Dollars in thousands) Commercial Loan Portfolio Consumer Loan Portfolio Total Allowance for loan losses balance at December 31, 2016 attributable to: Loans individually evaluated for impairment $ 5,234 $ 4,158 $ 9,392 Loans collectively evaluated for impairment 45,967 22,909 68,876 Loans acquired with deteriorated credit quality — — — Total $ 51,201 $ 27,067 $ 78,268 Recorded investment (loan balance) at December 31, 2016: Loans individually evaluated for impairment $ 78,523 $ 28,346 $ 106,869 Loans collectively evaluated for impairment 4,026,526 3,325,006 7,351,532 Loans acquired with deteriorated credit quality 3,489,163 2,043,215 5,532,378 Total $ 7,594,212 $ 5,396,567 $ 12,990,779

Other Real Estate Owned and R32

Other Real Estate Owned and Repossessed Assets (Tables)	3 Months Ended
	Mar. 31, 2017
Other Real Estate [Abstract]
Tabular disclosure of the changes in non-covered and covered other real estate on properties owned	Changes in other real estate owned and repossessed assets, included in interest receivable and other assets on the consolidated statements of financial position, were as follows: (Dollars in thousands) Other real estate Repossessed Balance at January 1, 2017 $ 16,812 $ 375 Other additions (1) 3,119 1,162 Net payments received (39 ) — Disposals (3,728 ) (1,037 ) Write-downs (269 ) — Balance at March 31, 2017 $ 15,895 $ 500 Balance at January 1, 2016 $ 9,716 $ 219 Other additions (1) 938 729 Net payments received (185 ) (11 ) Disposals (1,371 ) (620 ) Write-downs (167 ) — Balance at March 31, 2016 $ 8,931 $ 317 (1) Includes loans transferred to other real estate owned and other repossessed assets.
Schedule of income and expenses related to other real estate owned	Income and expenses related to other real estate owned and repossessed assets, recorded as a component of "Other expense" in the Consolidated Statements of Income, were as follows: (Dollars in thousands) Other real estate owned Repossessed assets For the three months ended March 31, 2017 Net gain (loss) on sale $ 1,047 $ (78 ) Write-downs (269 ) — Net operating expenses (508 ) (3 ) Total $ 270 $ (81 ) For the three months ended March 31, 2016 Net gain (loss) on sale $ 722 $ (8 ) Write-downs (167 ) — Net operating expenses (153 ) (5 ) Total $ 402 $ (13 )

Loan Servicing Rights (Tables)

Loan Servicing Rights (Tables)	3 Months Ended
	Mar. 31, 2017
Transfers and Servicing [Abstract]
Schedule of activity for loan servicing rights and the related fair value changes	The following table represents the activity for LSRs and the related fair value changes: For the three months ended March 31, 2017 (Dollars in thousands) Commercial Real Estate Mortgage Total Fair value, beginning of period $ 344 $ 47,741 $ 48,085 Transfers based on new accounting policy election — 15,891 15,891 Additions from loans sold with servicing retained — 1,753 1,753 Changes in fair value due to: Reductions from pay-offs, pay downs and run-off (24 ) (582 ) (606 ) Changes in estimates of fair value (1) — (519 ) (519 ) Fair value, end of period $ 320 $ 64,284 $ 64,604 Principal balance of loans serviced for others that have servicing capitalized $ 50,942 $ 7,253,396 $ 7,304,338 (1) Represents estimated LSR value change resulting primarily from market-driven changes in interest rates and prepayments. Included in "Mortgage banking revenue" in the Consolidated Statements of Income.
Activity for capitalized loan servicing rights	Activity for LSRs and the related valuation allowance for the three months ended March 31, 2016 are as follows: (Dollars in thousands) For the three months ended March 31, 2016 Balance at beginning of period $ 11,122 Additions 331 Amortization (975 ) Balance at end of period $ 10,478
Schedule of assumptions included in loan servicing rights	The following table presents assumptions utilized in determining the fair value of loan servicing rights as of March 31, 2017 and December 31, 2016 . Mortgage As of March 31, 2017 Prepayment speed 0.0 - 36.6% Weighted average (“WA”) discount rate 10.1 % Cost to service/per year $ 65 Ancillary income/per year $ 31 WA float range 0.98 % As of December 31, 2016 Prepayment speed 0.0 - 99.8% WA discount rate 10.1 % Cost to service/per year $65-$90 Ancillary income/per year $ 28 WA float range 1.0 %

Other Intangible Assets (Tables

Other Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Net carrying value of intangible assets	The following table shows the net carrying value of the Corporation’s other intangible assets: (Dollars in thousands) March 31, December 31, Core deposit intangible assets $ 38,723 $ 40,211 Non-compete intangible assets 125 — Total other intangible assets $ 38,848 $ 40,211
Carrying amount, accumulated amortization and amortization expense of core deposit intangible assets	The following table sets forth the carrying amount and accumulated amortization of core deposit intangible assets that are amortizable and arose from business combinations or other acquisitions: (Dollars in thousands) March 31, December 31, Gross original amount $ 59,143 $ 59,143 Accumulated amortization 20,420 18,932 Net carrying amount $ 38,723 $ 40,211

Derivative Instruments and Ba35

Derivative Instruments and Balance Sheet Offsetting (Tables)	3 Months Ended
	Mar. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule reflecting the amount and fair value of risk management derivatives and mortgage banking and customer initiated derivatives	The following table presents the notional amount and fair value of the Corporation’s derivative instruments held or issued in connection with customer-initiated and mortgage banking activities. March 31, 2017 December 31, 2016 Fair Value Fair Value (Dollars in thousands) Notional Amount (1) Gross Derivative Assets (2) Gross Derivative Liabilities (2) Notional Amount (1) Gross Derivative Assets (2) Gross Derivative Liabilities (2) Customer-initiated and mortgage banking derivatives: Customer-initiated derivatives $ 837,903 $ 6,377 $ 6,342 $ 600,598 $ 4,406 $ 4,141 Forward contracts related to mortgage loans to be delivered for sale 121,008 — 342 140,155 635 — Interest rate lock commitments 96,764 2,178 — 76,034 956 — Power Equity CD 37,635 2,234 2,234 36,807 2,218 2,218 Total gross derivatives $ 1,093,310 $ 10,789 $ 8,918 $ 853,594 $ 8,215 $ 6,359 (1) Notional or contract amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the Consolidated Statements of Financial Position. (2) Derivative assets are included within "Other assets" and derivative liabilities are included within "Other liabilities" on the Consolidated Statements of Financial Position. Included in the fair value of the derivative assets are credit valuation adjustments for counterparty credit risk totaling $138 thousand at March 31, 2017 and $99 thousand at December 31, 2016 .
Schedule reflecting the net gains (losses) relating to derivative instruments related to the changes in fair value	The following table presents the net gains (losses) related to derivative instruments reflecting the changes in fair value. Three Months Ended March 31, (Dollars in thousands) Location of Gain (Loss) 2017 2016 Forward contracts related to mortgage loans to be delivered for sale Mortgage banking revenue $ (977 ) $ (233 ) Interest rate lock commitments Mortgage banking revenue 1,223 161 Customer-initiated derivatives Other noninterest income (231 ) — Total gain (loss) recognized in income $ 15 $ (72 )
Schedule of the Company's financial instruments eligible for offset, offsetting assets	The tables below present information about the Corporation’s financial instruments that are eligible for offset. Gross amounts not offset in the (Dollars in thousands) Gross Gross amounts Net amounts Financial Collateral Net March 31, 2017 Offsetting derivative assets Derivative assets $ 6,355 $ — $ 6,355 $ — $ (450 ) $ 5,905 Offsetting derivative liabilities Derivative liabilities 6,342 — 6,342 — 7,506 (1,164 ) December 31, 2016 Offsetting derivative assets Derivative assets $ 4,405 $ — $ 4,405 $ — $ — $ 4,405 Offsetting derivative liabilities Derivative liabilities 4,141 — 4,141 — 2,550 1,591
Schedule of the Company's financial instruments eligible for offset, offsetting liabilities	The tables below present information about the Corporation’s financial instruments that are eligible for offset. Gross amounts not offset in the (Dollars in thousands) Gross Gross amounts Net amounts Financial Collateral Net March 31, 2017 Offsetting derivative assets Derivative assets $ 6,355 $ — $ 6,355 $ — $ (450 ) $ 5,905 Offsetting derivative liabilities Derivative liabilities 6,342 — 6,342 — 7,506 (1,164 ) December 31, 2016 Offsetting derivative assets Derivative assets $ 4,405 $ — $ 4,405 $ — $ — $ 4,405 Offsetting derivative liabilities Derivative liabilities 4,141 — 4,141 — 2,550 1,591

Commitments, Contingencies an36

Commitments, Contingencies and Guarantees (Tables)	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Summary of the reserve for unfunded commitments	A summary of the reserve for unfunded commitments of the Corporation is as follows: For the three months ended March 31, (Dollars in thousands) 2017 2016 Reserve balance at beginning of period $ 6,459 $ 4,048 Reserve reduction (770 ) (150 ) Charge-offs — (73 ) Ending reserve balance $ 5,689 $ 3,825 (Dollars in thousands) March 31, 2017 December 31, 2016 Reserve balance Liability for specific claims 529 730 General allowance 5,160 5,729 Total reserve balance $ 5,689 $ 6,459

Borrowings (Tables)

Borrowings (Tables)	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Schedule of Other Borrowings	A summary of the Corporation's short- and long-term borrowings follows: March 31, December 31, (Dollars in thousands) Amount Weighted Average Rate (1) Amount Weighted Average Rate (1) Securities sold under agreements to repurchase with customers: Securities sold under agreements to repurchase with customers $ 398,910 0.18 % $ 343,047 0.16 % Short-term borrowings: FHLB advances: 0.66% - 0.89% fixed-rate notes 900,000 0.79 825,000 0.65 Long-term borrowings: FHLB advances: 0.92% - 7.44% fixed-rate notes due 2017 to 2020 (2) 386,417 2.11 438,538 1.24 Securities sold under agreements to repurchase: 1.48% - 2.75% fixed-rate notes due in 2017 (3) 9,093 1.29 19,144 3.17 Line-of-credit: floating-rate based on one-month LIBOR plus 1.75% 79,783 2.53 124,625 2.52 Subordinated debt obligations: floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035 (4) 11,320 3.30 11,285 3.14 Subordinated debt obligations: floating-rate based on three-month LIBOR plus 3.25% due in 2032 (5) 4,263 4.40 4,255 4.25 Total long-term borrowings 490,876 2.21 597,847 1.63 Total borrowings $ 1,789,786 1.04 % $ 1,765,894 0.89 % (1) Weighted average rate presented is the contractual rate which excludes premiums and discounts related to purchase accounting. (2) The March 31, 2017 balances include advances payable of $385.9 million and purchase accounting premiums of $0.6 million . The December 31, 2016 balance includes advances payable of $437.8 million and purchase accounting premiums of $0.7 million . (3) The March 31, 2017 balance includes advances payable of $9.0 million and purchase accounting premiums of $0.1 million . The December 31, 2016 balance includes advance payable of $19.0 million and purchase accounting premiums of $0.1 million . (4) The March 31, 2017 balance includes advances payable of $15.0 million and purchase accounting discounts of $3.7 million . The December 31, 2016 balance includes advances payable of $15.0 million and purchase accounting discounts of $3.7 million . (5) The March 31, 2017 balance includes advances payable of $5.0 million and purchase accounting discounts of $0.7 million . The December 31, 2016 balance includes advances payable of $5.0 million and purchase accounting discounts of $0.7 million .
Schedule of Securities Sold Under Agreements to Repurchase	The remaining contractual maturity, excluding purchase accounting adjustments, of long-term securities under agreement to repurchase, is as follows: March 31, 2017 Remaining Contractual Maturities of the Agreements (Dollars in thousands) Overnight and continuous Up to 30 Days 30-90 Days Greater than 90 Days Total Securities sold under agreements to repurchase $ — $ — $ — $ 9,000 $ 9,000 Total borrowings $ — $ — $ — $ 9,000 $ 9,000 Amounts related to securities sold under agreements to repurchase not included in offsetting disclosure in Footnote 10 $ 9,000

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Schedule of reconciliation of expected income tax expense (benefit) at the federal statutory rate to the Company’s provision for income taxes and effective tax rate	A reconciliation of expected income tax expense at the federal statutory income tax rate and the amounts recorded in the Consolidated Financial Statements were as follows: Three Months Ended March 31, 2017 2016 (Dollars in thousands) Amount Rate Amount Rate Tax at statutory rate $ 20,951 35.0 % $ 11,677 35.0 % Changes resulting from: Tax-exempt interest income (1,757 ) (2.9 ) (1,139 ) (3.4 ) State taxes, net of federal benefit 212 0.4 — — Change in valuation allowance 11 — — — Bank-owned life insurance adjustments (344 ) (0.6 ) (68 ) (0.2 ) Income tax credits, net (695 ) (1.2 ) (797 ) (2.4 ) Tax benefits in excess of compensation costs on share-based payments (6,134 ) (10.2 ) (343 ) (1.0 ) Other, net 13 — 427 1.2 Income tax expense $ 12,257 20.5 % $ 9,757 29.2 %

Share-Based Compensation (Table

Share-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of activity for Corporation's stock options	A summary of activity for the Corporation’s stock options as of and for the three months ended March 31, 2017 is presented below: Non-Vested Stock Options Outstanding Stock Options Outstanding Number of Options Weighted- Average Exercise Price Per Share Weighted- Average Grant Date Fair Value Per Share Number of Options Weighted- Average Exercise Price Per Share Outstanding at December 31, 2016 407,939 $ 32.81 $ 6.15 2,453,395 $ 21.41 Granted 126,695 53.72 10.05 126,695 53.72 Exercised — — — (1,210,264 ) 15.92 Vested (81,584 ) 32.81 6.15 — — Forfeited/expired (3,940 ) 32.81 6.15 (3,940 ) 32.81 Outstanding at March 31, 2017 449,110 $ 38.71 $ 7.25 1,365,886 $ 29.24 Exercisable/vested at March 31, 2017 916,776 $ 24.60
Assumptions of Black-Scholes option pricing model	The fair value of the stock options granted during the three months ended March 31, 2017 was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions. Expected dividend yield 3.32 % Risk-free interest rate 2.06 % Expected stock price volatility 26.9 % Expected life of options – in years 6.0 Weighted average fair value of options granted $ 10.05
Summary of activity for restricted stock units and awards	The following table provides information regarding nonvested restricted stock awards: Nonvested restricted stock awards Number of Awards Weighted-average acquisition-date Nonvested at January 1, 2017 365,891 $ 46.23 Vested (61,049 ) 46.23 Forfeited (1,524 ) 46.23 Nonvested at March 31, 2017 303,318 $ 46.23 A summary of the activity for restricted stock units as of and for the three months ended March 31, 2017 is presented below: Number of Units Weighted-average grant date fair value per unit Outstanding at December 31, 2016 298,357 $ 32.81 Granted 159,462 52.11 Converted into shares of common stock (40,141 ) 26.86 Forfeited/expired (316 ) 32.81 Outstanding at March 31, 2017 417,362 $ 40.76

Pension and Other Postretirem40

Pension and Other Postretirement Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2017
Compensation and Retirement Disclosure [Abstract]
Components of net periodic benefit cost (income) for the Corporation's qualified and nonqualified pension plans and nonqualified postretirement benefits plan	The components of net periodic benefit cost for the Corporation’s qualified and nonqualified pension plans and nonqualified postretirement benefit plan are as follows: Three Months Ended March 31, (Dollars in thousands) 2017 2016 Defined Benefit Pension Plans Service cost $ 233 $ 277 Interest cost 1,302 1,358 Expected return on plan assets (2,217 ) (2,141 ) Amortization of unrecognized net loss 578 572 Net periodic benefit cost (income) $ (104 ) $ 66 Postretirement Benefit Plan Service cost $ 1 $ 2 Interest cost 24 33 Amortization of prior service cost — 29 Amortization of unrecognized net gain (41 ) (24 ) Net periodic benefit cost (income) $ (16 ) $ 40

Regulatory Capital (Tables)

Regulatory Capital (Tables)	3 Months Ended
	Mar. 31, 2017
Banking and Thrift [Abstract]
Corporation's and Chemical Bank's actual capital amounts and ratios with the quantitative measures established by regulation to ensure capital adequacy	The summary below compares the actual capital amounts and ratios with the quantitative measures established by regulation to ensure capital adequacy: Actual Minimum Required for Capital Adequacy Purposes Minimum Required for Capital Adequacy Purposes Plus Capital Conservation Buffer Required to be Well Capitalized Under Prompt Corrective Action Regulations (Dollars in thousands) Capital Amount Ratio Capital Amount Ratio Capital Amount Ratio Capital Amount Ratio March 31, 2017 Total Capital to Risk-Weighted Assets Corporation $ 1,547,145 11.4 % $ 1,089,998 8.0 % $ 1,260,310 9.3 % N/A N/A Chemical Bank 1,581,814 11.7 1,086,008 8.0 1,255,696 9.3 $ 1,357,510 10.0 % Tier 1 Capital to Risk-Weighted Assets Corporation 1,445,929 10.6 817,498 6.0 987,810 7.3 N/A N/A Chemical Bank 1,496,181 11.0 814,506 6.0 984,195 7.3 1,086,008 8.0 Common Equity Tier 1 Capital to Risk-Weighted Assets Corporation 1,445,929 10.6 613,124 4.5 783,436 5.8 N/A N/A Chemical Bank 1,496,181 11.0 610,879 4.5 780,568 5.8 882,381 6.5 Leverage Ratio Corporation 1,445,929 8.9 651,811 4.0 651,811 4.0 N/A N/A Chemical Bank 1,496,181 9.2 650,356 4.0 650,356 4.0 812,945 5.0 December 31, 2016 Total Capital to Risk-Weighted Assets Corporation $ 1,543,018 11.5 % $ 1,073,431 8.0 % $ 1,157,293 8.6 % N/A N/A Chemical Bank 1,608,980 12.0 1,068,560 8.0 1,152,041 8.6 $ 1,335,700 10.0 % Tier 1 Capital to Risk-Weighted Assets Corporation 1,441,209 10.7 805,073 6.0 888,935 6.6 N/A N/A Chemical Bank 1,522,711 11.4 801,420 6.0 884,901 6.6 1,068,560 8.0 Common Equity Tier 1 Capital to Risk-Weighted Asset Corporation 1,441,209 10.7 603,805 4.5 687,667 5.1 N/A N/A Chemical Bank 1,522,711 11.4 601,065 4.5 684,546 5.1 868,205 6.5 Leverage Ratio Corporation 1,441,209 9.0 643,603 4.0 643,603 4.0 N/A N/A Chemical Bank 1,522,711 9.5 641,457 4.0 641,457 4.0 801,822 5.0

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	3 Months Ended
	Mar. 31, 2017
Earnings Per Share [Abstract]
Numerator and denominator of the basic and diluted earnings per common share computations	The factors used in the earnings per share computation follow: Three Months Ended March 31, (In thousands, except per share data) 2017 2016 Net income $ 47,604 $ 23,605 Net income allocated to participating securities 226 — Net income allocated to common shareholders (1) $ 47,378 $ 23,605 Weighted average common shares - issued 70,969 38,198 Average unvested restricted share awards (341 ) — Weighted average common shares outstanding - basic 70,628 38,198 Effect of dilutive securities Weighted average common stock equivalents 787 323 Weighted average common shares outstanding - diluted 71,415 38,521 EPS available to common shareholders Basic earnings per common share $ 0.67 $ 0.61 Diluted earnings per common share $ 0.67 $ 0.60 (1) Net income allocated to common shareholders for basic and diluted earnings per share may differ under the two-class method as a result of adding common share equivalents for options and warrants to dilutive shares outstanding, which alters the ratio used to allocate net income to common shareholders and participating securities for the purposes of calculating diluted earnings per share.

Accumulated Other Comprehensi43

Accumulated Other Comprehensive Loss (Tables)	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Components of accumulated other comprehensive loss, net of related tax benefit/expense	The following table summarizes the changes within each component of accumulated other comprehensive income (loss), net of related tax benefit/expense for the three months ended March 31, 2017 , and 2016 : (Dollars in thousands) Unrealized gains Defined Benefit Pension Plans Total For the three months ended March 31, 2017 Beginning balance $ (14,142 ) $ (25,894 ) $ (40,036 ) Other comprehensive income before reclassifications 1,780 — 1,780 Amounts reclassified from accumulated other comprehensive income (58 ) 349 291 Net current period other comprehensive income 1,722 349 2,071 Ending balance $ (12,420 ) $ (25,545 ) $ (37,965 ) For the three months ended March 31, 2016 Beginning balance $ (1,888 ) $ (27,144 ) $ (29,032 ) Other comprehensive income before reclassifications 2,729 — 2,729 Amounts reclassified from accumulated other comprehensive income (12 ) (375 ) (387 ) Net current period other comprehensive income (loss) 2,717 (375 ) 2,342 Ending balance $ 829 $ (27,519 ) $ (26,690 )
Summary of amounts reclassified out of accumulated other comprehensive income (loss)	The following table summarizes the amounts reclassified out of each component of accumulated other comprehensive income (loss) for the three months ended March 31, 2017 , and 2016 : (Dollars in thousands) Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Income Statement Three Months Ended March 31, 2017 2016 Gains and losses on available-for-sale securities $ 90 $ 19 Gain on sale of investment securities (noninterest income) (32 ) (7 ) Income tax (expense)/benefit $ 58 $ 12 Net Income Amortization of defined benefit pension plan items $ 537 $ 577 Salaries, wages and employee benefits (operating expenses) (188 ) (202 ) Income tax (expense)/benefit $ 349 $ 375 Net Income

Basis of Presentation and Sig44

Basis of Presentation and Significant Accounting Policies (Details)		3 Months Ended
		Mar. 31, 2017USD ($)Bank	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)
Accounting Policies [Abstract]
Number of banks through which company operates (in bank) | Bank		1
Number of regional banking units Chemical Bank operates through (in bank) | Bank		7
Business Acquisition
Cumulative effect adjustment of change in accounting policy, net of tax impact	[1]			$ 3,659,000
Expense related to qualified affordable housing projects		$ 800,000	$ 600,000
Remaining investment in qualified affordable housing projects		31,800,000		29,500,000
Equity method investments		10,700,000		10,900,000
Remaining unfunded equity contributions		18,500,000		16,000,000
Impairment on tax credit projects		$ 0		0
Retained earnings
Business Acquisition
Cumulative effect adjustment of change in accounting policy, net of tax impact	[1]			$ 3,659,000
[1]	Refer to Footnote 1, Basis of Presentation and Accounting Policies and Footnote 8, Loan Servicing Rights, for further details on this change in accounting policy election.

Mergers and Acquisitions - Text

Mergers and Acquisitions - Textual (Details) $ / shares in Units, $ in Thousands, shares in Millions	Aug. 31, 2016USD ($)$ / sharesshares	Mar. 31, 2017USD ($)	Mar. 31, 2016USD ($)
Business Acquisition
Repayments of lines of credit	$ 25,000
Merger and acquisition-related transaction expenses		$ 4,167	$ 2,594
Talmer
Business Acquisition
Acquisition purchase price	$ 1,612,449
Stock consideration given (in shares) | shares	32.1
Exchange ratio of common stock issued	0.4725
Share price (in dollars per share) | $ / shares	$ 1.61
Credit facility used for acquisition	$ 125,000
Repayments of lines of credit	$ 37,500

Mergers and Acquisitions - Asse

Mergers and Acquisitions - Assets Acquired and Liabilities Assumed (Details) - Talmer Bank $ in Thousands	Aug. 31, 2016USD ($)
Consideration paid:
Stock	$ 1,504,811
Cash	107,638
Total consideration	1,612,449
Fair value of identifiable assets acquired:
Cash and cash equivalents	433,352
Investment securities:
Available-for-sale	808,894
Held-to-maturity	1,657
Loans held-for-sale	244,916
Loans	4,882,402
Premises and equipment	38,793
Loan servicing rights	42,462
Other intangible assets	19,088
Interest receivable and other assets	395,119
Total identifiable assets acquired	6,866,683
Fair value of liabilities assumed:
Noninterest-bearing deposits	1,236,902
Interest-bearing deposits	4,057,716
Interest payable and other liabilities	99,482
Securities sold under agreements to repurchase with customers	19,704
Short-term borrowings	387,500
Long-term borrowings	299,597
Total liabilities assumed	6,100,901
Fair value of net identifiable assets acquired	765,782
Goodwill resulting from acquisition	$ 846,667

Mergers and Acquisitions - Loan

Mergers and Acquisitions - Loans Accounted for Under ASC 310-30 (Details) - Talmer Bank $ in Thousands	Aug. 31, 2016USD ($)
Accounted for under ASC 310-30:
Contractual cash flows	$ 5,968,488
Contractual cash flows not expected to be collected (nonaccretable difference)	223,959
Expected cash flows	5,744,529
Interest component of expected cash flows (accretable yield)	862,127
Fair value at acquisition	$ 4,882,402

Mergers and Acquisitions - Pro

Mergers and Acquisitions - Pro Forma Information (Details) - Talmer Bank - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Business Acquisition
Net interest and other income	$ 168,107	$ 157,932
Net Income	$ 47,604	$ 39,028
Earnings per share:
Basic (in dollars per share)	$ 0.67	$ 0.56
Diluted (in dollars per share)	$ 0.67	$ 0.55

Fair Value Measurements - Asset

Fair Value Measurements - Assets on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	$ 1,275,846	$ 1,234,964
Loan servicing rights	64,604	48,085
U.S. Treasury securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,793
Government sponsored agencies
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	224,339	215,011
State and political subdivisions
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	300,409	300,088
Residential mortgage-backed securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	256,544	272,282
Collateralized mortgage obligations
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	367,321	320,025
Corporate bonds
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	89,253	89,474
Preferred stock and trust preferred securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	32,187	32,291
Recurring
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	1,275,846	1,234,964
Loans held-for-sale	39,123	81,830
Loan servicing rights	64,604	48,085
Total derivatives	10,789	8,215
Total assets measured at fair value on a recurring basis	1,390,362	1,373,094
Total derivatives	8,918	6,359
Total liabilities at fair value	8,918	6,359
Recurring | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,793
Loans held-for-sale	0	0
Loan servicing rights	0	0
Total derivatives	0	0
Total assets measured at fair value on a recurring basis	5,793	5,793
Total derivatives	0	0
Total liabilities at fair value	0	0
Recurring | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	1,270,053	1,229,171
Loans held-for-sale	39,123	81,830
Loan servicing rights	0	0
Total derivatives	10,789	8,215
Total assets measured at fair value on a recurring basis	1,319,965	1,319,216
Total derivatives	8,918	6,359
Total liabilities at fair value	8,918	6,359
Recurring | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Loans held-for-sale	0	0
Loan servicing rights	64,604	48,085
Total derivatives	0	0
Total assets measured at fair value on a recurring basis	64,604	48,085
Total derivatives	0	0
Total liabilities at fair value	0	0
Recurring | Customer-initiated derivatives
Summary of assets measured at fair value on a recurring basis
Total derivatives	6,377	4,406
Total derivatives	6,342	4,141
Recurring | Customer-initiated derivatives | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Total derivatives	0	0
Total derivatives	0	0
Recurring | Customer-initiated derivatives | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Total derivatives	6,377	4,406
Total derivatives	6,342	4,141
Recurring | Customer-initiated derivatives | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Total derivatives	0	0
Total derivatives	0	0
Recurring | Forward contracts related to mortgage loans to be delivered for sale
Summary of assets measured at fair value on a recurring basis
Total derivatives		635
Total derivatives	342
Recurring | Forward contracts related to mortgage loans to be delivered for sale | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Total derivatives		0
Total derivatives	0
Recurring | Forward contracts related to mortgage loans to be delivered for sale | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Total derivatives		635
Total derivatives	342
Recurring | Forward contracts related to mortgage loans to be delivered for sale | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Total derivatives		0
Total derivatives	0
Recurring | Interest rate lock commitments
Summary of assets measured at fair value on a recurring basis
Total derivatives	2,178	956
Recurring | Interest rate lock commitments | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Total derivatives	0	0
Recurring | Interest rate lock commitments | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Total derivatives	2,178	956
Recurring | Interest rate lock commitments | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Total derivatives	0	0
Recurring | Power Equity CD
Summary of assets measured at fair value on a recurring basis
Total derivatives	2,234	2,218
Total derivatives	2,234	2,218
Recurring | Power Equity CD | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Total derivatives	0	0
Total derivatives	0	0
Recurring | Power Equity CD | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Total derivatives	2,234	2,218
Total derivatives	2,234	2,218
Recurring | Power Equity CD | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Total derivatives	0	0
Total derivatives	0	0
Recurring | U.S. Treasury securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,793
Recurring | U.S. Treasury securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,793
Recurring | U.S. Treasury securities | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | U.S. Treasury securities | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Government sponsored agencies
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	224,339	215,011
Recurring | Government sponsored agencies | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Government sponsored agencies | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	224,339	215,011
Recurring | Government sponsored agencies | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | State and political subdivisions
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	300,409	300,088
Recurring | State and political subdivisions | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | State and political subdivisions | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	300,409	300,088
Recurring | State and political subdivisions | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Residential mortgage-backed securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	256,544	272,282
Recurring | Residential mortgage-backed securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Residential mortgage-backed securities | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	256,544	272,282
Recurring | Residential mortgage-backed securities | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Collateralized mortgage obligations
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	367,321	320,025
Recurring | Collateralized mortgage obligations | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Collateralized mortgage obligations | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	367,321	320,025
Recurring | Collateralized mortgage obligations | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Corporate bonds
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	89,253	89,474
Recurring | Corporate bonds | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Corporate bonds | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	89,253	89,474
Recurring | Corporate bonds | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Preferred stock and trust preferred securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	32,187	32,291
Recurring | Preferred stock and trust preferred securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Preferred stock and trust preferred securities | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	32,187	32,291
Recurring | Preferred stock and trust preferred securities | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	$ 0	$ 0

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Level 3 Assets (Details) - Recurring - Loan servicing rights $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 48,085
Transfer in based on new accounting policy election	15,891
Gains (losses): Recorded in earnings (realized)	(1,125)
New originations	1,753
Balance, end of period	$ 64,604

Fair Value Measurements - Aggre

Fair Value Measurements - Aggregate Fair Value, Contractual Balance, and Gain or Loss for Loans Held-For-Sale (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Aggregate fair value	$ 39,123	$ 81,830
Contractual balance	37,701	81,009
Unrealized gain (loss)	$ 1,422	$ 821

Fair Value Measurements - Gains

Fair Value Measurements - Gains (Losses) from Loans Held-for-Sale (Details) - Loans Held For Sale - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total included in earnings	$ 1,152	$ 19
Interest income
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total included in earnings	551	19
Mortgage banking revenue
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total included in earnings	$ 601	$ 0

Fair Value Measurements - Textu

Fair Value Measurements - Textual (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Fair Value Measurements (Textual) [Abstract]
Impairment of goodwill	$ 0	$ 0
Core deposit intangible assets
Fair Value Measurements (Textual) [Abstract]
Impairment valuation allowance	0
Impairment identified for intangible assets		0
Loan servicing rights
Fair Value Measurements (Textual) [Abstract]
Impairment valuation allowance	$ 8,000	0
Minimum
Fair Value Measurements (Textual) [Abstract]
Expected life of intangible assets	10 years
Maximum
Fair Value Measurements (Textual) [Abstract]
Expected life of intangible assets	15 years
Loans Held For Sale
Fair Value Measurements (Textual) [Abstract]
Loans held for sale that were on nonaccrual status	$ 0	0
Loans held for sale that were 90 days past due and on accrual status	$ 0	0
Total Impaired Loans | Minimum
Fair Value Measurements (Textual) [Abstract]
Percentage of discount factors used to determine fair value	10.00%
Total Impaired Loans | Maximum
Fair Value Measurements (Textual) [Abstract]
Percentage of discount factors used to determine fair value	25.00%
Other Real Estate and Repossessed Assets | Minimum
Fair Value Measurements (Textual) [Abstract]
Percentage of discount factors used to determine fair value	10.00%
Other Real Estate and Repossessed Assets | Maximum
Fair Value Measurements (Textual) [Abstract]
Percentage of discount factors used to determine fair value	25.00%
Measured on a Recurring Basis
Fair Value Measurements (Textual) [Abstract]
Liabilities recorded at fair value	$ 8,918,000	6,359,000
Measured on a Nonrecurring Basis
Fair Value Measurements (Textual) [Abstract]
Liabilities recorded at fair value	0	0
Total assets measured at fair value on a nonrecurring basis	65,420,000	63,572,000
Measured on a Nonrecurring Basis | Impaired originated loans
Fair Value Measurements (Textual) [Abstract]
Total assets measured at fair value on a nonrecurring basis	$ 63,180,000	62,184,000
Measured on a Nonrecurring Basis | Loan servicing rights
Fair Value Measurements (Textual) [Abstract]
Total assets measured at fair value on a nonrecurring basis		$ 2,000

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value of Assets on a Nonrecurring Basis (Details) - Nonrecurring - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	$ 65,420	$ 63,572
Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0
Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0
Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	65,420	63,572
Impaired originated loans
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	63,180	62,184
Impaired originated loans | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0
Impaired originated loans | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0
Impaired originated loans | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	63,180	62,184
Other real estate/repossessed assets
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	2,240	1,386
Other real estate/repossessed assets | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0
Other real estate/repossessed assets | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	0	0
Other real estate/repossessed assets | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis	$ 2,240	1,386
Loan servicing rights
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis		2
Loan servicing rights | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis		0
Loan servicing rights | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis		0
Loan servicing rights | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a nonrecurring basis
Total assets measured at fair value on a nonrecurring basis		$ 2

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Assets, Nonrecurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Impaired originated loans | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	10.00%
Impaired originated loans | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	25.00%
Other Real Estate and Repossessed Assets | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	10.00%
Other Real Estate and Repossessed Assets | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	25.00%
Nonrecurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis	$ 65,420	$ 63,572
Nonrecurring | Impaired originated loans
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis	63,180	62,184
Nonrecurring | Other real estate/repossessed assets
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis	2,240	1,386
Nonrecurring | Loan servicing rights
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis		2
Nonrecurring | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis	65,420	63,572
Nonrecurring | Level 3 | Impaired originated loans
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis	63,180	62,184
Nonrecurring | Level 3 | Other real estate/repossessed assets
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis	$ 2,240	1,386
Nonrecurring | Level 3 | Loan servicing rights
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Total assets measured at fair value on a nonrecurring basis		$ 2

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Amounts and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Investment securities:
Held-to-maturity	$ 639,800	$ 608,531
Carrying Amount | Level 1
Financial assets:
Cash and cash equivalents	441,780	474,402
Carrying Amount | Level 2
Investment securities:
Held-to-maturity	646,692	622,927
Nonmarketable equity securities	129,939	97,350
Interest receivable	45,863	42,235
Deposits:
Deposits without defined maturities	10,213,518	9,862,755
Time deposits	2,918,829	3,010,367
Total deposits	13,132,347	12,873,122
Interest payable	5,225	5,415
Securities sold under agreements to repurchase with customers	398,910	343,047
Short-term borrowings	900,000	825,000
Long-term borrowings	490,876	597,847
Carrying Amount | Level 3
Investment securities:
Held-to-maturity	500	500
Net loans	13,194,618	12,912,511
Fair Value | Level 1
Financial assets:
Cash and cash equivalents	441,780	474,402
Fair Value | Level 2
Investment securities:
Held-to-maturity	639,450	608,221
Nonmarketable equity securities	129,939	97,350
Interest receivable	45,863	42,235
Deposits:
Deposits without defined maturities	10,213,518	9,862,755
Time deposits	2,919,153	3,010,048
Total deposits	13,132,671	12,872,803
Interest payable	5,225	5,415
Securities sold under agreements to repurchase with customers	398,910	343,047
Short-term borrowings	899,777	825,000
Long-term borrowings	486,161	591,227
Fair Value | Level 3
Investment securities:
Held-to-maturity	350	310
Net loans	$ 13,347,793	$ 13,069,315

Investment Securities - Availab

Investment Securities - Available-For-Sale Investment (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Available-for-sale Securities
Amortized Cost	$ 1,294,954	$ 1,256,721
Unrealized Gains	1,483	1,566
Unrealized Losses	20,591	23,323
Available-for-sale, at fair value	1,275,846	1,234,964
U.S. Treasury securities
Available-for-sale Securities
Amortized Cost	5,792	5,788
Unrealized Gains	1	5
Unrealized Losses	0	0
Available-for-sale, at fair value	5,793	5,793
Government sponsored agencies
Available-for-sale Securities
Amortized Cost	225,993	216,890
Unrealized Gains	153	189
Unrealized Losses	1,807	2,068
Available-for-sale, at fair value	224,339	215,011
State and political subdivisions
Available-for-sale Securities
Amortized Cost	309,518	311,704
Unrealized Gains	140	163
Unrealized Losses	9,249	11,779
Available-for-sale, at fair value	300,409	300,088
Residential mortgage-backed securities
Available-for-sale Securities
Amortized Cost	260,703	276,162
Unrealized Gains	45	112
Unrealized Losses	4,204	3,992
Available-for-sale, at fair value	256,544	272,282
Collateralized mortgage obligations
Available-for-sale Securities
Amortized Cost	371,084	323,965
Unrealized Gains	75	63
Unrealized Losses	3,838	4,003
Available-for-sale, at fair value	367,321	320,025
Corporate bonds
Available-for-sale Securities
Amortized Cost	90,438	90,859
Unrealized Gains	27	16
Unrealized Losses	1,212	1,401
Available-for-sale, at fair value	89,253	89,474
Preferred stock and trust preferred securities
Available-for-sale Securities
Amortized Cost	31,426	31,353
Unrealized Gains	1,042	1,018
Unrealized Losses	281	80
Available-for-sale, at fair value	$ 32,187	$ 32,291

Investment Securities - Held-To

Investment Securities - Held-To-Maturity Investment (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Held-to-maturity Securities
Amortized Cost	$ 647,192	$ 623,427
Unrealized Gains	3,830	2,648
Unrealized Losses	11,222	17,544
Held-to-maturity, fair value	639,800	608,531
State and political subdivisions
Held-to-maturity Securities
Amortized Cost	646,692	622,927
Unrealized Gains	3,830	2,648
Unrealized Losses	11,072	17,354
Held-to-maturity, fair value	639,450	608,221
Trust preferred securities
Held-to-maturity Securities
Amortized Cost	500	500
Unrealized Gains	0	0
Unrealized Losses	150	190
Held-to-maturity, fair value	$ 350	$ 310

Investment Securities - Gains a

Investment Securities - Gains and (Losses) Recognized in Earnings (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Proceeds	$ 0	$ 644
Gross gains	$ 90	$ 19

Investment Securities - Maturit

Investment Securities - Maturities of Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Securities with amortized cost pledged to secure borrowings and deposits	$ 911,900	$ 794,000
Investment Securities Available-for-Sale:
Due in one year or less, Amortized Cost	248,015
Due after one year through five years, Amortized Cost	529,893
Due after five years through ten years, Amortized Cost	347,825
Due after ten years, Amortized Cost	167,832
Preferred stock, Amortized Cost	1,389
Total Available-for-sale Securities, Debt Maturities, Amortized Cost	1,294,954
Due in one year or less , Fair Value	246,683
Due after one year through five years, Fair Value	524,707
Due after five years through ten years, Fair Value	340,248
Due after ten years, Fair Value	162,405
Preferred stock, Fair Value	1,803
Total Available-for-sale securities, Debt maturities, Fair Value	1,275,846
Investment Securities Held-to-Maturity:
Due in one year or less, Amortized Cost	70,242
Due after one year through five years, Amortized Cost	271,055
Due after five years through ten years, Amortized Cost	146,712
Due after ten years, Amortized Cost	159,183
Total Held-to-maturity securities, Debt maturities, Amortized Cost	647,192	623,427
Due in one year or less , Fair Value	70,210
Due after one year through five years, Fair Value	268,753
Due after five years through ten years, Fair Value	144,004
Due after ten years, Fair Value	156,833
Total Held-to-maturity securities, Debt maturities, Fair Value	$ 639,800	$ 608,531

Investment Securities - Gross U

Investment Securities - Gross Unrealized Losses (Details) $ in Thousands	Mar. 31, 2017USD ($)security	Dec. 31, 2016USD ($)
Schedule of Investments [Line Items]
Total number of securities, available-for-sale and held-to-maturity | security	2,309
Securities in unrealized loss positions, qualitative disclosure, number of positions | security	1,418
Summary of continuous unrealized loss position of securities
Less Than 12 Months, Fair Value	$ 1,463,173	$ 1,478,240
Less Than 12 Months, Gross Unrealized Losses	30,370	39,116
12 Months or More, Fair Value	51,664	56,897
12 Months or More, Gross Unrealized Losses	1,443	1,751
Total, Fair Value	1,514,837	1,535,137
Total, Gross Unrealized Losses	31,813	40,867
Government sponsored agencies
Summary of continuous unrealized loss position of securities
Less Than 12 Months, Fair Value	108,300	105,702
Less Than 12 Months, Gross Unrealized Losses	1,445	1,707
12 Months or More, Fair Value	11,203	15,023
12 Months or More, Gross Unrealized Losses	362	361
Total, Fair Value	119,503	120,725
Total, Gross Unrealized Losses	1,807	2,068
State and political subdivisions
Summary of continuous unrealized loss position of securities
Less Than 12 Months, Fair Value	705,870	758,063
Less Than 12 Months, Gross Unrealized Losses	19,603	28,158
12 Months or More, Fair Value	26,084	26,810
12 Months or More, Gross Unrealized Losses	718	975
Total, Fair Value	731,954	784,873
Total, Gross Unrealized Losses	20,321	29,133
Residential mortgage-backed securities
Summary of continuous unrealized loss position of securities
Less Than 12 Months, Fair Value	248,111	244,239
Less Than 12 Months, Gross Unrealized Losses	4,204	3,992
12 Months or More, Fair Value	0	0
12 Months or More, Gross Unrealized Losses	0	0
Total, Fair Value	248,111	244,239
Total, Gross Unrealized Losses	4,204	3,992
Collateralized mortgage obligations
Summary of continuous unrealized loss position of securities
Less Than 12 Months, Fair Value	311,566	279,001
Less Than 12 Months, Gross Unrealized Losses	3,626	3,778
12 Months or More, Fair Value	12,528	14,754
12 Months or More, Gross Unrealized Losses	212	225
Total, Fair Value	324,094	293,755
Total, Gross Unrealized Losses	3,838	4,003
Corporate bonds
Summary of continuous unrealized loss position of securities
Less Than 12 Months, Fair Value	78,815	80,536
Less Than 12 Months, Gross Unrealized Losses	1,211	1,401
12 Months or More, Fair Value	1,499	0
12 Months or More, Gross Unrealized Losses	1	0
Total, Fair Value	80,314	80,536
Total, Gross Unrealized Losses	1,212	1,401
Trust preferred securities
Summary of continuous unrealized loss position of securities
Less Than 12 Months, Fair Value	10,511	10,699
Less Than 12 Months, Gross Unrealized Losses	281	80
12 Months or More, Fair Value	350	310
12 Months or More, Gross Unrealized Losses	150	190
Total, Fair Value	10,861	11,009
Total, Gross Unrealized Losses	$ 431	$ 270

Loans - Textual (Details)

Loans - Textual (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)class_of_loansegmentdirectortenantexecutive	Dec. 31, 2016USD ($)
Loans (Textual) [Abstract]
Number of portfolio segment (in segment) | segment	2
Number of classes of loans (in class of loan) | class_of_loan	6
Number of minimum tenants under lease of non-owner occupied commercial real estate (in tenant) | tenant	1
Minimum value of loan that requires regional loan committee approval	$ 2,000
Maximum value of loan that requires regional loan committee approval	$ 5,000
Minimum due period of loans consider in a nonperforming status	90 days
Total troubled debt restructurings	$ 85,000	$ 93,066
Residential mortgage loans in process of foreclosure	5,100	7,300
Commitment to lend additional funds to borrowers whose terms have been modified in TDRs	2,700
Talmer
Loans (Textual) [Abstract]
Reclassification from nonaccretable difference to accretable yield	21,100
Nonperforming
Loans (Textual) [Abstract]
Total troubled debt restructurings	27,942	30,531
Performing
Loans (Textual) [Abstract]
Total troubled debt restructurings	$ 57,058	62,535
Consumer loan portfolio
Loans (Textual) [Abstract]
Maximum due period of loans consider in performing status	90 days
Minimum due period of loans consider in a nonperforming status	90 days
Total troubled debt restructurings	$ 20,103	22,281
Consumer loan portfolio | Nonperforming
Loans (Textual) [Abstract]
Total troubled debt restructurings	4,100	5,134
Consumer loan portfolio | Performing
Loans (Textual) [Abstract]
Total troubled debt restructurings	16,003	17,147
Commercial loan portfolio
Loans (Textual) [Abstract]
Total troubled debt restructurings	64,897	70,785
Commercial loan portfolio | Nonperforming
Loans (Textual) [Abstract]
Total troubled debt restructurings	23,842	25,397
Commercial loan portfolio | Performing
Loans (Textual) [Abstract]
Total troubled debt restructurings	$ 41,055	$ 45,388
Land development loans
Loans (Textual) [Abstract]
Maximum period for payment of loan	12 months
Residential mortgage
Loans (Textual) [Abstract]
Lower limit of number of family residential properties (in tenant) | tenant	1
Upper limit of number of family residential properties (in tenant) | tenant	4
Period for loan secured under real estate residential security	15 years
Loan-to-value ratio at the time of origination (as a percent)	80.00%
Commercial | Commercial loan portfolio
Loans (Textual) [Abstract]
Minimum value of loan requires group loan authority approval	$ 2,000
Number of bank executives and senior officers with credit decision limits similar to group loan authorities (in executive) | executive	6
Minimum value of loan requires executive and senior officer approval	$ 2,000
Maximum value of loan requires executive and senior officer approval	3,500
Minimum value of loan requires group loan authority approval	5,000
Maximum value of loan requires group loan authority approval	$ 10,000
Number of members of the board of directors in loan committee (in director) | director	8
Commercial | Minimum | Commercial loan portfolio
Loans (Textual) [Abstract]
Minimum value of loans requiring only director loan committee approval	$ 10,000
Minimum value of loans depending on risk rating and requires credit action from board of directors	25,000
Commercial | Maximum | Commercial loan portfolio
Loans (Textual) [Abstract]
Other loans requiring director loan committee approval depending on risk rating and credit action required	$ 10,000

Loans - Summary of Loans (Detai

Loans - Summary of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Summary of loans under portfolio
Total loans	$ 13,273,392	$ 12,990,779
Deferred income	15,000	14,800
Commercial loan portfolio
Summary of loans under portfolio
Total loans	7,805,190	7,594,212
Commercial loan portfolio | Commercial
Summary of loans under portfolio
Total loans	3,253,608	3,217,300
Commercial loan portfolio | Commercial real estate
Summary of loans under portfolio
Total loans	4,097,771	3,973,140
Commercial loan portfolio | Real estate construction and land development
Summary of loans under portfolio
Total loans	453,811	403,772
Consumer loan portfolio
Summary of loans under portfolio
Total loans	5,468,202	5,396,567
Consumer loan portfolio | Residential mortgage
Summary of loans under portfolio
Total loans	3,133,465	3,086,474
Consumer loan portfolio | Consumer installment
Summary of loans under portfolio
Total loans	1,481,057	1,433,884
Consumer loan portfolio | Home equity
Summary of loans under portfolio
Total loans	853,680	876,209
Originated
Summary of loans under portfolio
Total loans	7,959,769	7,458,401
Originated | Commercial
Summary of loans under portfolio
Total loans	1,989,609	1,901,526
Originated | Commercial real estate
Summary of loans under portfolio
Total loans	2,114,540	1,921,799
Originated | Real estate construction and land development
Summary of loans under portfolio
Total loans	327,740	281,724
Originated | Residential mortgage
Summary of loans under portfolio
Total loans	1,594,376	1,475,342
Originated | Consumer installment
Summary of loans under portfolio
Total loans	1,342,063	1,282,588
Originated | Home equity
Summary of loans under portfolio
Total loans	591,441	595,422
Originated | Commercial loan portfolio
Summary of loans under portfolio
Total loans	4,431,889	4,105,049
Originated | Commercial loan portfolio | Commercial
Summary of loans under portfolio
Total loans	1,989,609	1,901,526
Originated | Commercial loan portfolio | Commercial real estate
Summary of loans under portfolio
Total loans	2,114,540	1,921,799
Originated | Commercial loan portfolio | Real estate construction and land development
Summary of loans under portfolio
Total loans	327,740	281,724
Originated | Consumer loan portfolio
Summary of loans under portfolio
Total loans	3,527,880	3,353,352
Originated | Consumer loan portfolio | Residential mortgage
Summary of loans under portfolio
Total loans	1,594,376	1,475,342
Originated | Consumer loan portfolio | Consumer installment
Summary of loans under portfolio
Total loans	1,342,063	1,282,588
Originated | Consumer loan portfolio | Home equity
Summary of loans under portfolio
Total loans	591,441	595,422
Acquired
Summary of loans under portfolio
Total loans	5,313,623	5,532,378
Acquired | Commercial loan portfolio
Summary of loans under portfolio
Total loans	3,373,301	3,489,163
Acquired | Commercial loan portfolio | Commercial
Summary of loans under portfolio
Total loans	1,263,999	1,315,774
Acquired | Commercial loan portfolio | Commercial real estate
Summary of loans under portfolio
Total loans	1,983,231	2,051,341
Acquired | Commercial loan portfolio | Real estate construction and land development
Summary of loans under portfolio
Total loans	126,071	122,048
Acquired | Consumer loan portfolio
Summary of loans under portfolio
Total loans	1,940,322	2,043,215
Acquired | Consumer loan portfolio | Residential mortgage
Summary of loans under portfolio
Total loans	1,539,089	1,611,132
Acquired | Consumer loan portfolio | Consumer installment
Summary of loans under portfolio
Total loans	138,994	151,296
Acquired | Consumer loan portfolio | Home equity
Summary of loans under portfolio
Total loans	$ 262,239	$ 280,787

Loans - Activity for Accretable

Loans - Activity for Accretable Yield (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Activity for accretable yield
Balance at beginning of period	$ 1,039,971	$ 298,257
Additions (reductions)	(515)	(6,681)
Accretion recognized in interest income	(60,187)	(16,962)
Reclassification from nonaccretable difference	21,139
Balance at end of period	1,000,408	274,614
Talmer
Activity for accretable yield
Balance at beginning of period	798,210	0
Additions (reductions)	0	0
Accretion recognized in interest income	(44,571)	0
Reclassification from nonaccretable difference	21,139
Balance at end of period	774,778	0
Lake Michigan
Activity for accretable yield
Balance at beginning of period	121,416	152,999
Additions (reductions)	(939)	(6,071)
Accretion recognized in interest income	(7,266)	(8,953)
Reclassification from nonaccretable difference	0
Balance at end of period	113,211	137,975
Monarch
Activity for accretable yield
Balance at beginning of period	27,182	34,558
Additions (reductions)	54	128
Accretion recognized in interest income	(1,181)	(1,451)
Reclassification from nonaccretable difference	0
Balance at end of period	26,055	33,235
North-western
Activity for accretable yield
Balance at beginning of period	69,847	82,623
Additions (reductions)	(1,058)	(2,254)
Accretion recognized in interest income	(3,892)	(4,001)
Reclassification from nonaccretable difference	0
Balance at end of period	64,897	76,368
OAK
Activity for accretable yield
Balance at beginning of period	23,316	28,077
Additions (reductions)	1,428	1,516
Accretion recognized in interest income	(3,277)	(2,557)
Reclassification from nonaccretable difference	0
Balance at end of period	$ 21,467	$ 27,036

Loans - Commercial Loans by Ris

Loans - Commercial Loans by Risk Rating Categories (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	$ 13,273,392	$ 12,990,779
Originated
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	7,959,769	7,458,401
Originated | Commercial
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,989,609	1,901,526
Originated | Commercial real estate
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	2,114,540	1,921,799
Originated | Real estate construction and land development
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	327,740	281,724
Acquired
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	5,313,623	5,532,378
Commercial loan portfolio
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	7,805,190	7,594,212
Commercial loan portfolio | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	7,404,839	7,167,397
Commercial loan portfolio | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	165,269	192,013
Commercial loan portfolio | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	234,881	233,479
Commercial loan portfolio | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	201	1,323
Commercial loan portfolio | Commercial
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	3,253,608	3,217,300
Commercial loan portfolio | Commercial real estate
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	4,097,771	3,973,140
Commercial loan portfolio | Real estate construction and land development
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	453,811	403,772
Commercial loan portfolio | Originated
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	4,431,889	4,105,049
Commercial loan portfolio | Originated | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	4,269,870	3,934,033
Commercial loan portfolio | Originated | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	72,265	81,947
Commercial loan portfolio | Originated | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	89,753	87,999
Commercial loan portfolio | Originated | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1	1,070
Commercial loan portfolio | Originated | Commercial
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,989,609	1,901,526
Commercial loan portfolio | Originated | Commercial | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,902,773	1,803,750
Commercial loan portfolio | Originated | Commercial | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	34,018	44,809
Commercial loan portfolio | Originated | Commercial | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	52,818	51,898
Commercial loan portfolio | Originated | Commercial | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	0	1,069
Commercial loan portfolio | Originated | Commercial real estate
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	2,114,540	1,921,799
Commercial loan portfolio | Originated | Commercial real estate | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	2,040,155	1,849,315
Commercial loan portfolio | Originated | Commercial real estate | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	37,528	36,981
Commercial loan portfolio | Originated | Commercial real estate | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	36,856	35,502
Commercial loan portfolio | Originated | Commercial real estate | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1	1
Commercial loan portfolio | Originated | Real estate construction and land development
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	327,740	281,724
Commercial loan portfolio | Originated | Real estate construction and land development | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	326,942	280,968
Commercial loan portfolio | Originated | Real estate construction and land development | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	719	157
Commercial loan portfolio | Originated | Real estate construction and land development | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	79	599
Commercial loan portfolio | Originated | Real estate construction and land development | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	0	0
Commercial loan portfolio | Acquired
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	3,373,301	3,489,163
Commercial loan portfolio | Acquired | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	3,134,969	3,233,364
Commercial loan portfolio | Acquired | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	93,004	110,066
Commercial loan portfolio | Acquired | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	145,128	145,480
Commercial loan portfolio | Acquired | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	200	253
Commercial loan portfolio | Acquired | Commercial
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,263,999	1,315,774
Commercial loan portfolio | Acquired | Commercial | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,171,260	1,218,848
Commercial loan portfolio | Acquired | Commercial | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	39,079	46,643
Commercial loan portfolio | Acquired | Commercial | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	53,625	50,283
Commercial loan portfolio | Acquired | Commercial | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	35	0
Commercial loan portfolio | Acquired | Commercial real estate
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,983,231	2,051,341
Commercial loan portfolio | Acquired | Commercial real estate | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,841,116	1,897,011
Commercial loan portfolio | Acquired | Commercial real estate | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	52,038	61,441
Commercial loan portfolio | Acquired | Commercial real estate | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	89,912	92,636
Commercial loan portfolio | Acquired | Commercial real estate | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	165	253
Commercial loan portfolio | Acquired | Real estate construction and land development
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	126,071	122,048
Commercial loan portfolio | Acquired | Real estate construction and land development | Pass
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	122,593	117,505
Commercial loan portfolio | Acquired | Real estate construction and land development | Special Mention
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,887	1,982
Commercial loan portfolio | Acquired | Real estate construction and land development | Substandard
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	1,591	2,561
Commercial loan portfolio | Acquired | Real estate construction and land development | Doubtful
Recorded investment of loans in commercial loan portfolio by risk rating categories
Total loans	$ 0	$ 0

Loans - Consumer Loans by Risk

Loans - Consumer Loans by Risk Rating Categories (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	$ 13,273,392	$ 12,990,779
Originated
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	7,959,769	7,458,401
Originated | Residential mortgage
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,594,376	1,475,342
Originated | Consumer installment
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,342,063	1,282,588
Originated | Home equity
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	591,441	595,422
Acquired
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	5,313,623	5,532,378
Consumer loan portfolio
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	5,468,202	5,396,567
Consumer loan portfolio | Residential mortgage
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	3,133,465	3,086,474
Consumer loan portfolio | Consumer installment
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,481,057	1,433,884
Consumer loan portfolio | Home equity
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	853,680	876,209
Consumer loan portfolio | Originated
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	3,527,880	3,353,352
Consumer loan portfolio | Originated | Residential mortgage
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,594,376	1,475,342
Consumer loan portfolio | Originated | Consumer installment
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,342,063	1,282,588
Consumer loan portfolio | Originated | Home equity
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	591,441	595,422
Consumer loan portfolio | Originated | Performing
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	3,517,663	3,342,153
Consumer loan portfolio | Originated | Performing | Residential mortgage
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,587,627	1,468,373
Consumer loan portfolio | Originated | Performing | Consumer installment
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,341,308	1,281,709
Consumer loan portfolio | Originated | Performing | Home equity
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	588,728	592,071
Consumer loan portfolio | Originated | Nonperforming
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	10,217	11,199
Consumer loan portfolio | Originated | Nonperforming | Residential mortgage
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	6,749	6,969
Consumer loan portfolio | Originated | Nonperforming | Consumer installment
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	755	879
Consumer loan portfolio | Originated | Nonperforming | Home equity
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	2,713	3,351
Consumer loan portfolio | Acquired
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,940,322	2,043,215
Consumer loan portfolio | Acquired | Residential mortgage
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	1,539,089	1,611,132
Consumer loan portfolio | Acquired | Consumer installment
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	138,994	151,296
Consumer loan portfolio | Acquired | Home equity
Recorded investment of loans in consumer loan portfolio based on credit risk profile of loans in performing and nonperforming status
Total loans	$ 262,239	$ 280,787

Loans - Nonperforming Loans (De

Loans - Nonperforming Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Summary of nonperforming loans
Total accruing loans contractually past due 90 days or more as to interest or principal payments	$ 3,692	$ 1,283
Commercial
Summary of nonperforming loans
Total accruing loans contractually past due 90 days or more as to interest or principal payments	1,823	11
Commercial real estate
Summary of nonperforming loans
Total accruing loans contractually past due 90 days or more as to interest or principal payments	700	277
Home equity
Summary of nonperforming loans
Total accruing loans contractually past due 90 days or more as to interest or principal payments	1,169	995
Nonperforming
Summary of nonperforming loans
Total nonaccrual loans	47,841	44,334
Other real estate owned and repossessed assets	16,395	17,187
Total nonperforming assets	64,236	61,521
Nonperforming | Commercial
Summary of nonperforming loans
Total nonaccrual loans	16,717	13,178
Nonperforming | Commercial real estate
Summary of nonperforming loans
Total nonaccrual loans	20,828	19,877
Nonperforming | Real estate construction and land development
Summary of nonperforming loans
Total nonaccrual loans	79	80
Nonperforming | Residential mortgage
Summary of nonperforming loans
Total nonaccrual loans	6,749	6,969
Nonperforming | Consumer installment
Summary of nonperforming loans
Total nonaccrual loans	755	879
Nonperforming | Home equity
Summary of nonperforming loans
Total nonaccrual loans	$ 2,713	$ 3,351

Loans - Aging Status of Loans (

Loans - Aging Status of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Schedule representing the aging status of the recorded investment in loans by classes
Total loans	$ 13,273,392	$ 12,990,779
90 days or more past due and still accruing	3,692	1,283
Commercial
Schedule representing the aging status of the recorded investment in loans by classes
90 days or more past due and still accruing	1,823	11
Commercial real estate
Schedule representing the aging status of the recorded investment in loans by classes
90 days or more past due and still accruing	700	277
Home equity
Schedule representing the aging status of the recorded investment in loans by classes
90 days or more past due and still accruing	1,169	995
Originated Portfolio
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	76,262	51,633
Current	7,883,507	7,406,768
Total loans	7,959,769	7,458,401
90 days or more past due and still accruing	3,692	1,283
Originated Portfolio | 30-59 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	43,509	29,928
Originated Portfolio | 60-89 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	15,364	8,560
Originated Portfolio | 90 days or more past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	17,389	13,145
Originated Portfolio | Commercial
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	28,675	18,904
Current	1,960,934	1,882,622
Total loans	1,989,609	1,901,526
90 days or more past due and still accruing	1,823	11
Originated Portfolio | Commercial | 30-59 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	10,603	10,421
Originated Portfolio | Commercial | 60-89 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	9,411	4,842
Originated Portfolio | Commercial | 90 days or more past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	8,661	3,641
Originated Portfolio | Commercial real estate
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	18,353	13,305
Current	2,096,187	1,908,494
Total loans	2,114,540	1,921,799
90 days or more past due and still accruing	700	277
Originated Portfolio | Commercial real estate | 30-59 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	9,712	6,551
Originated Portfolio | Commercial real estate | 60-89 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	2,625	1,589
Originated Portfolio | Commercial real estate | 90 days or more past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	6,016	5,165
Originated Portfolio | Real estate construction and land development
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	5,265	3,220
Current	322,475	278,504
Total loans	327,740	281,724
90 days or more past due and still accruing	0	0
Originated Portfolio | Real estate construction and land development | 30-59 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	3,495	2,721
Originated Portfolio | Real estate construction and land development | 60-89 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	1,770	499
Originated Portfolio | Real estate construction and land development | 90 days or more past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	0	0
Originated Portfolio | Residential mortgage
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	14,590	4,961
Current	1,579,786	1,470,381
Total loans	1,594,376	1,475,342
90 days or more past due and still accruing	0	0
Originated Portfolio | Residential mortgage | 30-59 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	12,918	3,147
Originated Portfolio | Residential mortgage | 60-89 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	731	62
Originated Portfolio | Residential mortgage | 90 days or more past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	941	1,752
Originated Portfolio | Consumer installment
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	3,315	4,904
Current	1,338,748	1,277,684
Total loans	1,342,063	1,282,588
90 days or more past due and still accruing	0	0
Originated Portfolio | Consumer installment | 30-59 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	2,805	3,991
Originated Portfolio | Consumer installment | 60-89 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	275	675
Originated Portfolio | Consumer installment | 90 days or more past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	235	238
Originated Portfolio | Home equity
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	6,064	6,339
Current	585,377	589,083
Total loans	591,441	595,422
90 days or more past due and still accruing	1,169	995
Originated Portfolio | Home equity | 30-59 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	3,976	3,097
Originated Portfolio | Home equity | 60-89 days past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	552	893
Originated Portfolio | Home equity | 90 days or more past due
Schedule representing the aging status of the recorded investment in loans by classes
Total past due	$ 1,536	$ 2,349

Loans - Impaired Loans by Class

Loans - Impaired Loans by Class (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Impaired loans with a valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	$ 68,820	$ 74,740
Unpaid Principal Balance	77,882	85,264
Related Valuation Allowance	5,640	9,392
Impaired loans with no valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	36,079	32,129
Unpaid Principal Balance	45,739	38,794
Related Valuation Allowance	0	0
Total Impaired Loans
Schedule of Impaired loans by classes
Recorded Investment	104,899	106,869
Unpaid Principal Balance	123,621	124,058
Related Valuation Allowance	5,640	9,392
Commercial | Impaired loans with a valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	26,201	28,925
Unpaid Principal Balance	29,804	33,209
Related Valuation Allowance	2,468	3,128
Commercial | Impaired loans with no valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	9,028	7,435
Unpaid Principal Balance	14,910	11,153
Related Valuation Allowance	0	0
Commercial | Total Impaired Loans
Schedule of Impaired loans by classes
Recorded Investment	35,229	36,360
Unpaid Principal Balance	44,714	44,362
Related Valuation Allowance	2,468	3,128
Commercial real estate | Impaired loans with a valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	20,416	21,318
Unpaid Principal Balance	25,875	27,558
Related Valuation Allowance	1,251	2,102
Commercial real estate | Impaired loans with no valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	22,791	20,588
Unpaid Principal Balance	26,569	23,535
Related Valuation Allowance	0	0
Commercial real estate | Total Impaired Loans
Schedule of Impaired loans by classes
Recorded Investment	43,207	41,906
Unpaid Principal Balance	52,444	51,093
Related Valuation Allowance	1,251	2,102
Real estate construction and land development | Impaired loans with a valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	164	177
Unpaid Principal Balance	164	177
Related Valuation Allowance	2	4
Real estate construction and land development | Impaired loans with no valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	79	80
Unpaid Principal Balance	79	80
Related Valuation Allowance	0	0
Real estate construction and land development | Total Impaired Loans
Schedule of Impaired loans by classes
Recorded Investment	243	257
Unpaid Principal Balance	243	257
Related Valuation Allowance	2	4
Residential mortgage | Impaired loans with a valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	16,944	20,864
Unpaid Principal Balance	16,944	20,864
Related Valuation Allowance	1,162	3,528
Residential mortgage | Impaired loans with no valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	3,607	3,252
Unpaid Principal Balance	3,607	3,252
Related Valuation Allowance	0	0
Residential mortgage | Total Impaired Loans
Schedule of Impaired loans by classes
Recorded Investment	20,551	24,116
Unpaid Principal Balance	20,551	24,116
Related Valuation Allowance	1,162	3,528
Consumer installment | Impaired loans with a valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	799	879
Unpaid Principal Balance	799	879
Related Valuation Allowance	102	240
Consumer installment | Impaired loans with no valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	62
Unpaid Principal Balance	62
Related Valuation Allowance	0
Consumer installment | Total Impaired Loans
Schedule of Impaired loans by classes
Recorded Investment	861	879
Unpaid Principal Balance	861	879
Related Valuation Allowance	102	240
Home equity | Impaired loans with a valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	4,296	2,577
Unpaid Principal Balance	4,296	2,577
Related Valuation Allowance	655	390
Home equity | Impaired loans with no valuation allowance
Schedule of Impaired loans by classes
Recorded Investment	512	774
Unpaid Principal Balance	512	774
Related Valuation Allowance	0	0
Home equity | Total Impaired Loans
Schedule of Impaired loans by classes
Recorded Investment	4,808	3,351
Unpaid Principal Balance	4,808	3,351
Related Valuation Allowance	$ 655	$ 390

Loans - Impaired Loans (Details

Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Average recorded investment
Impaired loans with a valuation allowance	$ 68,157	$ 39,131
Impaired loans with no related valuation allowance	37,754	85,936
Total impaired loans	105,911	125,067
Interest income recognized while on impaired status
Impaired loans with a valuation allowance	264	333
Impaired loans with no related valuation allowance	563	663
Total impaired loans	827	996
Commercial
Average recorded investment
Impaired loans with a valuation allowance	25,712	10,551
Impaired loans with no related valuation allowance	9,297	31,404
Total impaired loans	35,009	41,955
Interest income recognized while on impaired status
Impaired loans with a valuation allowance	0	0
Impaired loans with no related valuation allowance	255	277
Total impaired loans	255	277
Commercial real estate
Average recorded investment
Impaired loans with a valuation allowance	20,035	7,592
Impaired loans with no related valuation allowance	23,473	45,737
Total impaired loans	43,508	53,329
Interest income recognized while on impaired status
Impaired loans with a valuation allowance	0	0
Impaired loans with no related valuation allowance	306	380
Total impaired loans	306	380
Real estate construction and land development
Average recorded investment
Impaired loans with a valuation allowance	161	0
Impaired loans with no related valuation allowance	81	918
Total impaired loans	242	918
Interest income recognized while on impaired status
Impaired loans with a valuation allowance	0	0
Impaired loans with no related valuation allowance	2	6
Total impaired loans	2	6
Residential mortgage
Average recorded investment
Impaired loans with a valuation allowance	17,398	20,988
Impaired loans with no related valuation allowance	3,808	5,149
Total impaired loans	21,206	26,137
Interest income recognized while on impaired status
Impaired loans with a valuation allowance	264	333
Impaired loans with no related valuation allowance	0	0
Total impaired loans	264	333
Consumer installment
Average recorded investment
Impaired loans with a valuation allowance	780	0
Impaired loans with no related valuation allowance	215	340
Total impaired loans	995	340
Interest income recognized while on impaired status
Impaired loans with a valuation allowance	0	0
Impaired loans with no related valuation allowance	0	0
Total impaired loans	0	0
Home equity
Average recorded investment
Impaired loans with a valuation allowance	4,071	0
Impaired loans with no related valuation allowance	880	2,388
Total impaired loans	4,951	2,388
Interest income recognized while on impaired status
Impaired loans with a valuation allowance	0	0
Impaired loans with no related valuation allowance	0	0
Total impaired loans	$ 0	$ 0

Loans - Loan Modifications by C

Loans - Loan Modifications by Concession Type (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)loan	Mar. 31, 2016USD ($)loan
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 2,471	$ 5,023
Total number of loans | loan	12	18
Pre-modification recorded investment	$ 2,535	$ 5,023
Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	716	4,986
Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	1,176	37
Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	579	0
Commercial loan portfolio
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 2,252	$ 4,819
Total number of loans | loan	8	11
Pre-modification recorded investment	$ 2,261	$ 4,819
Commercial loan portfolio | Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	497	4,819
Commercial loan portfolio | Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	1,176	0
Commercial loan portfolio | Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	579	0
Commercial loan portfolio | Commercial
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 1,730	$ 3,832
Total number of loans | loan	5	7
Pre-modification recorded investment	$ 1,739	$ 3,832
Commercial loan portfolio | Commercial | Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	50	3,832
Commercial loan portfolio | Commercial | Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	1,101	0
Commercial loan portfolio | Commercial | Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	579	0
Commercial loan portfolio | Commercial real estate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 522	$ 987
Total number of loans | loan	3	4
Pre-modification recorded investment	$ 522	$ 987
Commercial loan portfolio | Commercial real estate | Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	447	987
Commercial loan portfolio | Commercial real estate | Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	75	0
Commercial loan portfolio | Commercial real estate | Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	0
Consumer loan portfolio
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 219	$ 204
Total number of loans | loan	4	7
Pre-modification recorded investment	$ 274	$ 204
Consumer loan portfolio | Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	219	167
Consumer loan portfolio | Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	37
Consumer loan portfolio | Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	0
Consumer loan portfolio | Residential mortgage
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 98	$ 105
Total number of loans | loan	1	1
Pre-modification recorded investment	$ 98	$ 105
Consumer loan portfolio | Residential mortgage | Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	98	105
Consumer loan portfolio | Residential mortgage | Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	0
Consumer loan portfolio | Residential mortgage | Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	0
Consumer loan portfolio | Consumer installment
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 10	$ 33
Total number of loans | loan	2	4
Pre-modification recorded investment	$ 11	$ 33
Consumer loan portfolio | Consumer installment | Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	10	33
Consumer loan portfolio | Consumer installment | Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	0
Consumer loan portfolio | Consumer installment | Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	0
Consumer loan portfolio | Home equity
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 111	$ 66
Total number of loans | loan	1	2
Pre-modification recorded investment	$ 165	$ 66
Consumer loan portfolio | Home equity | Principal deferral
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	111	29
Consumer loan portfolio | Home equity | Interest rate
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	0	37
Consumer loan portfolio | Home equity | Forbearance agreement
Financing Receivable, Modifications [Line Items]
Post-modification recorded investment	$ 0	$ 0

Loans - Summary of TDRs (Detail

Loans - Summary of TDRs (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Financing Receivable, Modifications [Line Items]
Total TDRs	$ 85,000	$ 93,066
Commercial loan portfolio
Financing Receivable, Modifications [Line Items]
Total TDRs	64,897	70,785
Consumer loan portfolio
Financing Receivable, Modifications [Line Items]
Total TDRs	20,103	22,281
Accruing TDRs
Financing Receivable, Modifications [Line Items]
Total TDRs	57,058	62,535
Accruing TDRs | Commercial loan portfolio
Financing Receivable, Modifications [Line Items]
Total TDRs	41,055	45,388
Accruing TDRs | Consumer loan portfolio
Financing Receivable, Modifications [Line Items]
Total TDRs	16,003	17,147
Nonaccrual TDRs
Financing Receivable, Modifications [Line Items]
Total TDRs	27,942	30,531
Nonaccrual TDRs | Commercial loan portfolio
Financing Receivable, Modifications [Line Items]
Total TDRs	23,842	25,397
Nonaccrual TDRs | Consumer loan portfolio
Financing Receivable, Modifications [Line Items]
Total TDRs	$ 4,100	$ 5,134

Loans - TDRs with a Payment Def

Loans - TDRs with a Payment Default During the Period (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)loan	Mar. 31, 2016USD ($)loan
Troubled debt restructurings on financing receivables with defaults payment
Number of loans (in loan) | loan	5	2
Principal balance | $	$ 725	$ 933
Commercial loan portfolio
Troubled debt restructurings on financing receivables with defaults payment
Number of loans (in loan) | loan	3	1
Principal balance | $	$ 620	$ 933
Commercial loan portfolio | Commercial
Troubled debt restructurings on financing receivables with defaults payment
Number of loans (in loan) | loan	3	0
Principal balance | $	$ 620	$ 0
Commercial loan portfolio | Commercial real estate
Troubled debt restructurings on financing receivables with defaults payment
Number of loans (in loan) | loan	0	1
Principal balance | $	$ 0	$ 933
Consumer loan portfolio
Troubled debt restructurings on financing receivables with defaults payment
Number of loans (in loan) | loan	2	1
Principal balance | $	$ 105	$ 0

Loans - Allowance for Loan Loss

Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Dec. 31, 2016
Schedule of allowance and recorded investment related to financing receivables segregated by portfolio segment
Beginning balance	$ 78,268	$ 73,328
Provision for loan losses	4,050	1,500
Charge-offs	(5,574)	(5,458)
Recoveries	2,030	948
Ending balance	78,774	70,318
Allowance for loan losses
Loans individually evaluated for impairment			$ 5,640	$ 9,392
Loans collectively evaluated for impairment			73,134	68,876
Loans acquired with deteriorated credit quality			0	0
Total allowance for loan losses	78,268	73,328	78,774	78,268
Recorded investment (loan balance)
Loans individually evaluated for impairment			104,899	106,869
Loans collectively evaluated for impairment			7,854,870	7,351,532
Loans acquired with deteriorated credit quality			5,313,623	5,532,378
Total loans			13,273,392	12,990,779
Commercial loan portfolio
Schedule of allowance and recorded investment related to financing receivables segregated by portfolio segment
Beginning balance	51,201	47,234
Provision for loan losses	4,392	1,000
Charge-offs	(2,691)	(3,896)
Recoveries	1,413	330
Ending balance	54,315	44,668
Allowance for loan losses
Loans individually evaluated for impairment			3,721	5,234
Loans collectively evaluated for impairment			50,594	45,967
Loans acquired with deteriorated credit quality			0	0
Total allowance for loan losses	51,201	47,234	54,315	51,201
Recorded investment (loan balance)
Loans individually evaluated for impairment			78,679	78,523
Loans collectively evaluated for impairment			4,353,210	4,026,526
Loans acquired with deteriorated credit quality			3,373,301	3,489,163
Total loans			7,805,190	7,594,212
Consumer loan portfolio
Schedule of allowance and recorded investment related to financing receivables segregated by portfolio segment
Beginning balance	27,067	26,094
Provision for loan losses	(342)	500
Charge-offs	(2,883)	(1,562)
Recoveries	617	618
Ending balance	24,459	25,650
Allowance for loan losses
Loans individually evaluated for impairment			1,919	4,158
Loans collectively evaluated for impairment			22,540	22,909
Loans acquired with deteriorated credit quality			0	0
Total allowance for loan losses	$ 27,067	$ 26,094	24,459	27,067
Recorded investment (loan balance)
Loans individually evaluated for impairment			26,220	28,346
Loans collectively evaluated for impairment			3,501,660	3,325,006
Loans acquired with deteriorated credit quality			1,940,322	2,043,215
Total loans			$ 5,468,202	$ 5,396,567

Other Real Estate Owned and R75

Other Real Estate Owned and Repossessed Assets - Rollforward Tables (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Changes in other real estate owned
Balance at the beginning of the period	$ 16,812	$ 9,716
Other additions	3,119	938
Net payments received	(39)	(185)
Disposals	(3,728)	(1,371)
Write-downs	(269)	(167)
Balance at the end of the period	15,895	8,931
Changes in repossessed assets
Balance at the beginning of the period	375	219
Other additions	1,162	729
Net payments received	0	(11)
Disposals	(1,037)	(620)
Write-downs	0	0
Balance at the end of the period	$ 500	$ 317

Other Real Estate Owned and R76

Other Real Estate Owned and Repossessed Assets - Textual (Details) $ in Millions	Mar. 31, 2017USD ($)
Other Real Estate [Abstract]
Other real estate owned and repossessed assets acquired in accordance with ASU 2014-04	$ 1.2
Real estate properties for which formal foreclosure proceedings are in process	$ 5.1

Other Real Estate Owned and R77

Other Real Estate Owned and Repossessed Assets - Income and Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income and expenses related to other real estate owned
Net gain (loss) on sale	$ 1,047	$ 722
Write-downs	(269)	(167)
Net operating expenses	(508)	(153)
Total	270	402
Income and expenses related to repossessed assets
Net gain (loss) on sale	(78)	(8)
Write-downs	0	0
Net operating expenses	(3)	(5)
Total	$ (81)	$ (13)

Goodwill (Details)

Goodwill (Details) - USD ($)	Aug. 31, 2016	Mar. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill		$ 1,133,534,000	$ 1,133,534,000
Goodwill impairment		$ 0
Talmer
Goodwill [Line Items]
Goodwill acquired during period	$ 846,667,000

Loan Servicing Rights - LSRs Ac

Loan Servicing Rights - LSRs Activity (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Dec. 31, 2016
Loan Servicing Rights
Cumulative effect adjustment of change in accounting policy, net of tax impact	[1]		$ 3,659
Activity for loan servicing rights and the related fair value changes
Fair value, beginning of period		$ 48,085
Transfers based on new accounting policy election		15,891
Additions from loans sold with servicing retained		1,753
Changes in fair value due to:
Reductions from pay-offs, pay downs and run-off		(606)
Changes in estimates of fair value		(519)
Fair value, end of period		64,604
Principal balance of loans serviced for others that have servicing capitalized		7,304,338
Commercial real estate
Activity for loan servicing rights and the related fair value changes
Fair value, beginning of period		344
Transfers based on new accounting policy election		0
Additions from loans sold with servicing retained		0
Changes in fair value due to:
Reductions from pay-offs, pay downs and run-off		(24)
Changes in estimates of fair value		0
Fair value, end of period		320
Principal balance of loans serviced for others that have servicing capitalized		50,942
Residential mortgage
Activity for loan servicing rights and the related fair value changes
Fair value, beginning of period		47,741
Transfers based on new accounting policy election		15,891
Additions from loans sold with servicing retained		1,753
Changes in fair value due to:
Reductions from pay-offs, pay downs and run-off		(582)
Changes in estimates of fair value		(519)
Fair value, end of period		64,284
Principal balance of loans serviced for others that have servicing capitalized		$ 7,253,396
Retained earnings
Loan Servicing Rights
Cumulative effect adjustment of change in accounting policy, net of tax impact	[1]		$ 3,659
[1]	Refer to Footnote 1, Basis of Presentation and Accounting Policies and Footnote 8, Loan Servicing Rights, for further details on this change in accounting policy election.

Loan Servicing Rights - Activit

Loan Servicing Rights - Activity for Capitalized LSRs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Activity for Capitalized LSRs
Balance at beginning of period	$ 40,211
Amortization	(1,513)	$ (2,169)
Balance at end of period	$ 38,848
Loan servicing rights
Activity for Capitalized LSRs
Balance at beginning of period		11,122
Additions		331
Amortization		(975)
Balance at end of period		$ 10,478

Loan Servicing Rights - Assumpt

Loan Servicing Rights - Assumptions Used in Determining Fair Value (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Loan servicing rights
Loan servicing fee income	$ 4,500,000	$ 1,300,000
Mortgage
Loan servicing rights
Cost to service/per year	65
Ancillary income/per year	$ 31		$ 28
WA float range (as a percent)	0.98%
Mortgage | Minimum
Loan servicing rights
Prepayment speed (as a percent)	0.00%		0.00%
Cost to service/per year			$ 65
Mortgage | Maximum
Loan servicing rights
Prepayment speed (as a percent)	36.60%		99.80%
Cost to service/per year			$ 90
Mortgage | Weighted Average
Loan servicing rights
Discount rate (as a percent)	10.10%		10.10%
WA float range (as a percent)			1.00%

Other Intangible Assets - Intan

Other Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Carrying amount, accumulated amortization and amortization expense of core deposit intangible assets
Total intangible assets	$ 38,848	$ 40,211
Core deposit intangible assets
Carrying amount, accumulated amortization and amortization expense of core deposit intangible assets
Gross original amount	59,143	59,143
Accumulated amortization	20,420	18,932
Total intangible assets	38,723	40,211
Non-compete intangible assets
Carrying amount, accumulated amortization and amortization expense of core deposit intangible assets
Total intangible assets	$ 125	$ 0

Other Intangible Assets - Textu

Other Intangible Assets - Textual (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 1,513	$ 2,169
Core deposit intangible assets
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	1,500	$ 1,100
Estimated Future Amortization Expense, Fiscal Year Maturity [Abstract]
Remainder of 2017	4,500
2,018	5,700
2,019	5,400
2,020	4,900
2,021	4,500
2022 and thereafter	$ 13,800

Derivative Instruments and Ba84

Derivative Instruments and Balance Sheet Offsetting - Notional Amount and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Derivative instruments
Notional Amount	$ 1,093,310	$ 853,594
Gross Derivative Assets	10,789	8,215
Gross Derivative Liabilities	8,918	6,359
Credit valuation adjustments for counterparty credit risk	138	99
Not designated as hedging | Customer-initiated derivatives
Derivative instruments
Notional Amount	837,903	600,598
Gross Derivative Assets	6,377	4,406
Gross Derivative Liabilities	6,342	4,141
Not designated as hedging | Forward contracts related to mortgage loans to be delivered for sale
Derivative instruments
Notional Amount	121,008	140,155
Gross Derivative Assets	0	635
Gross Derivative Liabilities	342	0
Not designated as hedging | Interest rate lock commitments
Derivative instruments
Notional Amount	96,764	76,034
Gross Derivative Assets	2,178	956
Gross Derivative Liabilities	0	0
Not designated as hedging | Power Equity CD
Derivative instruments
Notional Amount	37,635	36,807
Gross Derivative Assets	2,234	2,218
Gross Derivative Liabilities	$ 2,234	$ 2,218

Derivative Instruments and Ba85

Derivative Instruments and Balance Sheet Offsetting - Net Gains (Losses) Related to Changes in Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Derivative instruments
Net gains (losses) relating to derivative instruments	$ 15	$ (72)
Forward contracts related to mortgage loans to be delivered for sale | Mortgage banking revenue
Derivative instruments
Net gains (losses) relating to derivative instruments	(977)	(233)
Interest rate lock commitments | Mortgage banking revenue
Derivative instruments
Net gains (losses) relating to derivative instruments	1,223	161
Customer-initiated derivatives | Other noninterest income
Derivative instruments
Net gains (losses) relating to derivative instruments	$ (231)	$ 0

Derivative Instruments and Ba86

Derivative Instruments and Balance Sheet Offsetting - Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Offsetting derivative assets
Gross amounts recognized	$ 10,789	$ 8,215
Offsetting derivative liabilities
Gross amounts recognized	8,918	6,359
Interest rate swaps and customer-initiated derivatives
Offsetting derivative assets
Gross amounts recognized	6,355	4,405
Gross amounts offset in the statements of financial condition	0	0
Net amounts presented in the statements of financial position	6,355	4,405
Gross amounts not offset in the statements of financial position
Financial instruments	0	0
Collateral (received)/posted	(450)	0
Net Amount	5,905	4,405
Offsetting derivative liabilities
Gross amounts recognized	6,342	4,141
Gross amounts offset in the statements of financial condition	0	0
Net amounts presented in the statements of financial position	6,342	4,141
Gross amounts not offset in the statements of financial position
Financial instruments	0	0
Collateral (received)/posted	7,506	2,550
Net Amount	$ (1,164)	$ 1,591

Commitments, Contingencies an87

Commitments, Contingencies and Guarantees - Commitments (Details) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Financial Guarantees (Textual) [Abstract]
Potential losses from standby letters of credit	$ 0	$ 0
Undisbursed loan commitments	565,600,000	578,200,000
Probable credit losses	1,000,000	1,300,000
Financial and Performance Standby Letters of Credit
Financial Guarantees (Textual) [Abstract]
Letters of credit outstanding	118,400,000	118,900,000
Commitments to Extend Credit
Financial Guarantees (Textual) [Abstract]
Loan commitments under financial guarantee	$ 2,650,000,000	$ 2,700,000,000

Commitments, Contingencies an88

Commitments, Contingencies and Guarantees - Contingencies and Guarantees (Details) - Performance Guarantee - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Loss Contingencies [Line Items]
Recorded liability	$ 15,400	$ 16,900
Maximum potential amount of undiscounted future payments	14,800	16,100
Recourse liability	$ 200	$ 200

Commitments, Contingencies an89

Commitments, Contingencies and Guarantees - Warranties (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Dec. 31, 2016
Changes in the activity related to liability recorded in connection with representations and warranties
Reserve balance at beginning of period	$ 6,459	$ 4,048
Reserve reduction	(770)	(150)
Charge-offs	0	(73)
Ending reserve balance	5,689	3,825
Reserve balance
Liability for specific claims			$ 529	$ 730
General allowance			5,160	5,729
Total reserve balance	$ 6,459	$ 4,048	$ 5,689	$ 6,459

Borrowings - Other Borrowings (

Borrowings - Other Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Long-term borrowings:
Amount	$ 490,876	$ 597,847
Weighted Average Rate	2.21%	1.63%
Total borrowings	$ 1,789,786	$ 1,765,894
Total short-term and long-term borrowings, Weighted Average Rate	1.04%	0.89%
0.66% - 0.89% fixed-rate notes | Minimum
Long-term borrowings:
Stated interest rate	0.66%
0.66% - 0.89% fixed-rate notes | Maximum
Long-term borrowings:
Stated interest rate	0.89%
FHLB Advances | 0.00% - 0.00% fixed-rate notes due 2016 to 2027
Long-term borrowings:
Amount	$ 386,417	$ 438,538
Weighted Average Rate	2.11%	1.24%
Advances payable from Federal Home Loan Banks	$ 385,900	$ 437,800
Purchase accounting premiums	$ 600	700
FHLB Advances | 0.00% - 0.00% fixed-rate notes due 2016 to 2027 | Minimum
Long-term borrowings:
Stated interest rate	0.92%
FHLB Advances | 0.00% - 0.00% fixed-rate notes due 2016 to 2027 | Maximum
Long-term borrowings:
Stated interest rate	7.44%
Securities sold under agreements to repurchase
Long-term borrowings:
Amount	$ 9,000
Securities sold under agreements to repurchase | 0.00% - 0.00% fixed-rate notes due 2016 to 2017
Long-term borrowings:
Amount	$ 9,093	$ 19,144
Weighted Average Rate	1.29%	3.17%
Purchase accounting premiums	$ 100	$ 100
Advances payable	$ 9,000	19,000
Securities sold under agreements to repurchase | 0.00% - 0.00% fixed-rate notes due 2016 to 2017 | Minimum
Long-term borrowings:
Stated interest rate	1.48%
Securities sold under agreements to repurchase | 0.00% - 0.00% fixed-rate notes due 2016 to 2017 | Maximum
Long-term borrowings:
Stated interest rate	2.75%
Line of credit
Long-term borrowings:
Amount	$ 79,783	$ 124,625
Weighted Average Rate	2.53%	2.52%
Spread on variable rate	1.75%
Subordinated debt obligations | Floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035
Long-term borrowings:
Amount	$ 11,320	$ 11,285
Weighted Average Rate	3.30%	3.14%
Advances payable	$ 15,000	$ 15,000
Purchase accounting discounts	$ 3,700	3,700
Subordinated debt obligations | Floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035 | Minimum
Long-term borrowings:
Spread on variable rate	1.45%
Subordinated debt obligations | Floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035 | Maximum
Long-term borrowings:
Spread on variable rate	2.85%
Subordinated debt obligations | Floating-rate based on three-month LIBOR plus 3.25% due in 2032
Long-term borrowings:
Amount	$ 4,263	$ 4,255
Weighted Average Rate	4.40%	4.25%
Spread on variable rate	3.25%
Advances payable	$ 5,000	$ 5,000
Purchase accounting discounts	700	700
Securities sold under agreements to repurchase
Short-term borrowings:
Amount	$ 398,910	$ 343,047
Weighted Average Rate	0.18%	0.16%
FHLB Advances | 0.66% - 0.89% fixed-rate notes
Short-term borrowings:
Amount	$ 900,000	$ 825,000
Weighted Average Rate	0.79%	0.65%

Borrowings - Textual (Details)

Borrowings - Textual (Details) $ in Millions	Mar. 31, 2017USD ($)
Debt Disclosure [Abstract]
FHLB advances	$ 5,170
Additional borrowing available through FHLB	$ 53.2

Borrowings - Securities Sold Un

Borrowings - Securities Sold Under Agreements to Repurchase (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total	$ 490,876	$ 597,847
Amounts related to securities sold under agreements to repurchase not included in offsetting disclosure in Footnote 10	9,000
Securities sold under agreements to repurchase
Debt Instrument [Line Items]
Overnight and continuous	0
Up to 30 Days	0
30-90 Days	0
Greater than 90 Days	9,000
Total	$ 9,000

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Amount
Tax at statutory rate	$ 20,951	$ 11,677
Changes resulting from:
Tax-exempt interest income	1,757	1,139
State taxes, net of federal benefit	212	0
Change in valuation allowance	11	0
Bank-owned life insurance adjustments	344	68
Income tax credits, net	695	797
Tax benefits in excess of compensation costs on share-based payments	(6,134)	(343)
Other, net	13	427
Income tax provision (benefit)	$ 12,257	$ 9,757
Rate
Tax at statutory rate	35.00%	35.00%
Changes resulting from:
Tax-exempt interest income	(2.90%)	(3.40%)
State taxes, net of federal benefit	0.40%	0.00%
Change in valuation allowance	0.00%	0.00%
Bank-owned life insurance adjustments	(0.60%)	(0.20%)
Income tax credits, net	(1.20%)	(2.40%)
Tax benefits in excess of compensation costs on share-based payments	(10.20%)	(1.00%)
Other, net	0.00%	1.20%
Effective federal income tax rate	20.50%	29.20%

Share-Based Compensation - Text

Share-Based Compensation - Textual (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)$ / sharesshares	Mar. 31, 2016USD ($)shares	Apr. 26, 2017shares	Apr. 20, 2015shares
Share-based Compensation Plans (Textual)
Share-based compensation expense	$ 3,800	$ 800
Excess tax benefit from share-based compensation	6,100	300
Cash received from option exercises	$ 906	498
Certain officers
Share-based Compensation Plans (Textual)
Corporation granted shares of common stock (in shares) | shares	13,300
Stock Incentive Plan of 2015
Share-based Compensation Plans (Textual)
Number of shares authorized under stock incentive plan (in shares) | shares				1,300,000
Common stock available for future grants under share-based compensation plans (in shares) | shares	287,348
Stock Incentive Plan of 2017 | Subsequent Event
Share-based Compensation Plans (Textual)
Number of shares authorized under stock incentive plan (in shares) | shares			1,750,000
Stock Incentive Plans After 2012
Share-based Compensation Plans (Textual)
Vesting period	5 years
Stock Incentive Plans Prior To 2013
Share-based Compensation Plans (Textual)
Vesting period	3 years
Stock options
Share-based Compensation Plans (Textual)
Stock option award vesting period	10 years
Outstanding in-the-money stock options, intrinsic value		$ 11,000
Stock issued from exercises (in shares) | shares	496,000	37,000
Stock options | Non Vested
Share-based Compensation Plans (Textual)
Corporation granted options to purchase common stock (in shares) | shares	126,695
Restricted stock units
Share-based Compensation Plans (Textual)
Corporation granted options to purchase restricted stock performance units (in shares) | shares	159,462
Stock issued from exercises (in shares) | shares	40,141
Unrecognized compensation expense	$ 13,400
Unrecognized compensation expense, period for recognition	3 years 4 months
Restricted stock units | Minimum
Share-based Compensation Plans (Textual)
Restricted stock performance units eligible to vest as a multiple of number of units granted	0.5
Restricted stock units | Maximum
Share-based Compensation Plans (Textual)
Restricted stock performance units eligible to vest as a multiple of number of units granted	1.5
Equity Option
Share-based Compensation Plans (Textual)
Weighted-average remaining contractual terms for outstanding stock options	6 years 11 months
Weighted-average remaining contractual terms for exercisable stock options	5 years 8 months
Outstanding in-the-money stock options, intrinsic value	$ 29,000
Exercisable in-the-money stock options, intrinsic value	$ 24,300
Closing price of common stock (dollars per share) | $ / shares	$ 51.15
Unrecognized compensation expense	$ 3,200
Unrecognized compensation expense, period for recognition	4 years 4 months
Restricted stock awards
Share-based Compensation Plans (Textual)
Unrecognized compensation expense	$ 4,800
Unrecognized compensation expense, period for recognition	1 year 22 days

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Option Activity (Details)	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Weighted- Average Grant Date Fair Value Per Share
Granted, Weighted Average Grant Date Fair Value (dollars per share)	$ 10.05
Stock Options | Non Vested
Number of Options
Beginning balance, Number of Options (in shares) | shares	407,939
Granted, Number of Options (in shares) | shares	126,695
Exercised, Number of Options (in shares) | shares	0
Vested, Number of Options (in shares) | shares	(81,584)
Forfeited/expired, Number of Options (in shares) | shares	(3,940)
Ending balance, Number of Options (in shares) | shares	449,110
Weighted- Average Exercise Price Per Share
Beginning balance, Weighted Average Exercise Price (dollars per share)	$ 32.81
Granted, Weighted Average Exercise Price (dollars per share)	53.72
Exercised, Weighted Average Exercise Price (dollars per share)	0
Vested, Weighted Average Exercise Price (dollars per share)	32.81
Forfeited/expired, Weighted Average Exercise Price (dollars per share)	32.81
Ending balance, Weighted Average Exercise Price (dollars per share)	38.71
Weighted- Average Grant Date Fair Value Per Share
Beginning balance (dollars per share)	6.15
Granted, Weighted Average Grant Date Fair Value (dollars per share)	10.05
Exercised, Weighted Average Grant Date Fair Value (dollars per share)	0
Vested, Weighted Average Grant Date Fair Value (dollars per share)	6.15
Forfeited/expired, Weighted Average Grant Date Fair Value (dollars per share)	6.15
Ending balance (dollars per share)	$ 7.25
Stock Options | Vested & Nonvested
Number of Options
Beginning balance, Number of Options (in shares) | shares	2,453,395
Granted, Number of Options (in shares) | shares	126,695
Exercised, Number of Options (in shares) | shares	(1,210,264)
Vested, Number of Options (in shares) | shares	0
Forfeited/expired, Number of Options (in shares) | shares	(3,940)
Ending balance, Number of Options (in shares) | shares	1,365,886
Weighted- Average Exercise Price Per Share
Beginning balance, Weighted Average Exercise Price (dollars per share)	$ 21.41
Granted, Weighted Average Exercise Price (dollars per share)	53.72
Exercised, Weighted Average Exercise Price (dollars per share)	15.92
Vested, Weighted Average Exercise Price (dollars per share)	0
Forfeited/expired, Weighted Average Exercise Price (dollars per share)	32.81
Ending balance, Weighted Average Exercise Price (dollars per share)	$ 29.24
Stock Options | Vested
Weighted- Average Grant Date Fair Value Per Share
Exercisable/vested, Number of Options (in shares) | shares	916,776
Exercisable/vested, Weighted Average Exercise Price (dollars per share)	$ 24.60

Share-Based Compensation - Blac

Share-Based Compensation - Black-Scholes Pricing Model Assumptions (Details)	3 Months Ended
	Mar. 31, 2017$ / shares
Assumptions of Black-Scholes option pricing model
Expected dividend yield	3.32%
Risk-free interest rate	2.06%
Expected stock price volatility	26.90%
Expected life of options – in years	6 years
Weighted average fair value of options granted	$ 10.05

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Unit and Award Activity (Details)	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Restricted Stock Units
Number of Units/Awards
Beginning balance (in shares) | shares	298,357
Granted (in shares) | shares	159,462
Converted into shares of common stock (in shares) | shares	(40,141)
Forfeited/expired (in shares) | shares	(316)
Ending balance (in shares) | shares	417,362
Weighted-average grant-date fair value
Beginning balance (dollars per share) | $ / shares	$ 32.81
Granted (dollars per share) | $ / shares	52.11
Converted into shares of common stock (dollars per share) | $ / shares	26.86
Forfeited/expired (dollars per share) | $ / shares	32.81
Ending balance (dollars per share) | $ / shares	$ 40.76
Restricted Stock Awards
Number of Units/Awards
Beginning balance (in shares) | shares	365,891
Vested (in shares) | shares	(61,049)
Forfeited/expired (in shares) | shares	(1,524)
Ending balance (in shares) | shares	303,318
Weighted-average grant-date fair value
Beginning balance (dollars per share) | $ / shares	$ 46.23
Vested (dollars per share) | $ / shares	46.23
Forfeited (dollars per share) | $ / shares	46.23
Ending balance (dollars per share) | $ / shares	$ 46.23

Pension and Other Postretirem98

Pension and Other Postretirement Benefit Plans - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Defined Benefit Pension Plans
Components of net periodic benefit cost (income) for the Corporation's qualified and nonqualified pension plans and nonqualified postretirement benefits plan
Service cost	$ 233	$ 277
Interest cost	1,302	1,358
Expected return on plan assets	(2,217)	(2,141)
Amortization of unrecognized net loss	578	572
Net periodic benefit cost (income)	(104)	66
Postretirement Benefit Plan
Components of net periodic benefit cost (income) for the Corporation's qualified and nonqualified pension plans and nonqualified postretirement benefits plan
Service cost	1	2
Interest cost	24	33
Amortization of prior service cost	0	29
Amortization of unrecognized net loss	(41)	(24)
Net periodic benefit cost (income)	$ (16)	$ 40

Pension and Other Postretirem99

Pension and Other Postretirement Benefit Plans - Textual (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Corporation match as a percentage of the participants' elective deferrals	50.00%
Maximum percent of participants' base compensation matched	4.00%
Employer contributions to Pentegra DB Plan	$ 0	$ 0
Chemical Financial Corporation
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible pay contribution to certain employees (as a percent)	4.00%
Employer total contribution amount	$ 2,500,000	$ 1,300,000
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Contribution to defined benefit pension plan	$ 0
Discount rate for pension plan expense (as a percent)	4.20%
Non-Qualified Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate for pension plan expense (as a percent)	3.60%

Regulatory Capital (Details)

Regulatory Capital (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 26, 2017	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Leverage Ratio
Cash dividends declared per common share (in dollars per share)		$ 0.27	$ 0.26
Subsequent Event
Leverage Ratio
Cash dividends declared per common share (in dollars per share)	$ 0.27
Corporation
Regulatory Capital
Risk weighted assets		$ 13,620,000		$ 13,420,000
Total Capital to Risk-Weighted Assets
Actual Amount		$ 1,547,145		$ 1,543,018
Actual Ratio		11.40%		11.50%
For Capital Adequacy Purposes Amount		$ 1,089,998		$ 1,073,431
For Capital Adequacy Purposes Ratio		8.00%		8.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 1,260,310		$ 1,157,293
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		9.30%		8.60%
Tier 1 Capital to Risk-Weighted Assets
Actual Amount		$ 1,445,929		$ 1,441,209
Actual Ratio		10.60%		10.70%
For Capital Adequacy Purposes Amount		$ 817,498		$ 805,073
For Capital Adequacy Purposes Ratio		6.00%		6.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 987,810		$ 888,935
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		7.30%		6.60%
Common Equity Tier 1 Capital to Risk-Weighted Assets
Actual Amount		$ 1,445,929		$ 1,441,209
Actual Ratio		10.60%		10.70%
For Capital Adequacy Purposes Amount		$ 613,124		$ 603,805
For Capital Adequacy Purposes Ratio		4.50%		4.50%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 783,436		$ 687,667
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		5.80%		5.10%
Leverage Ratio
Actual Amount		$ 1,445,929		$ 1,441,209
Actual Ratio		8.90%		9.00%
For Capital Adequacy Purposes Amount		$ 651,811		$ 643,603
For Capital Adequacy Purposes Ratio		4.00%		4.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 651,811		$ 643,603
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		4.00%		4.00%
Chemical Bank
Regulatory Capital
Risk weighted assets		$ 13,580,000		$ 13,360,000
Total Capital to Risk-Weighted Assets
Actual Amount		$ 1,581,814		$ 1,608,980
Actual Ratio		11.70%		12.00%
For Capital Adequacy Purposes Amount		$ 1,086,008		$ 1,068,560
For Capital Adequacy Purposes Ratio		8.00%		8.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 1,255,696		$ 1,152,041
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		9.30%		8.60%
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount		$ 1,357,510		$ 1,335,700
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio		10.00%		10.00%
Tier 1 Capital to Risk-Weighted Assets
Actual Amount		$ 1,496,181		$ 1,522,711
Actual Ratio		11.00%		11.40%
For Capital Adequacy Purposes Amount		$ 814,506		$ 801,420
For Capital Adequacy Purposes Ratio		6.00%		6.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 984,195		$ 884,901
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		7.30%		6.60%
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount		$ 1,086,008		$ 1,068,560
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio		8.00%		8.00%
Common Equity Tier 1 Capital to Risk-Weighted Assets
Actual Amount		$ 1,496,181		$ 1,522,711
Actual Ratio		11.00%		11.40%
For Capital Adequacy Purposes Amount		$ 610,879		$ 601,065
For Capital Adequacy Purposes Ratio		4.50%		4.50%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 780,568		$ 684,546
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		5.80%		5.10%
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount		$ 882,381		$ 868,205
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio		6.50%		6.50%
Leverage Ratio
Actual Amount		$ 1,496,181		$ 1,522,711
Actual Ratio		9.20%		9.50%
For Capital Adequacy Purposes Amount		$ 650,356		$ 641,457
For Capital Adequacy Purposes Ratio		4.00%		4.00%
For Capital Adequacy Purposes Plus Capital Conservation Buffer Amount		$ 650,356		$ 641,457
For Capital Adequacy Purposes Plus Capital Conservation Buffer Ratio		4.00%		4.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount		$ 812,945		$ 801,822
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio		5.00%		5.00%

Earnings Per Common Share (Deta

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Net income	$ 47,604	$ 23,605
Net income allocated to participating securities	226	0
Net income allocated to common shareholders	$ 47,378	$ 23,605
Weighted average common shares - issued (in shares)	70,969,000	38,198,000
Average unvested restricted share awards (in shares)	(341,000)	0
Weighted average common shares outstanding - basic (in shares)	70,628,000	38,198,000
Effect of dilutive securities
Weighted average common stock equivalents (in shares)	787,000	323,000
Weighted average common shares outstanding - diluted (in shares)	71,415,000	38,521,000
EPS available to common shareholders
Basic earnings per common share (dollars per share)	$ 0.67	$ 0.61
Diluted earnings per common share (dollars per share)	0.67	0.60
Average stock valuation (in dollars per share)	$ 51.81	$ 33.29
Stock Option
Schedule Of Earnings Per Share By Common Class [Line Items]
Average number of exercisable employee stock option awards that were not included in the computation of diluted earnings per common share (in shares)	0	121,050

Accumulated Other Comprehens102

Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Components of accumulated other comprehensive income (loss), net of related tax benefit/expense
Beginning balance	$ 2,581,526	$ 1,015,974
Other comprehensive income before reclassifications	1,780	2,729
Amounts reclassified from accumulated other comprehensive income	291	(387)
Other comprehensive income, net of tax	2,071	2,342
Ending balance	2,600,051	1,032,291
Unrealized gains (losses) on securities available-for-sale, net of tax
Components of accumulated other comprehensive income (loss), net of related tax benefit/expense
Beginning balance	(14,142)	(1,888)
Other comprehensive income before reclassifications	1,780	2,729
Amounts reclassified from accumulated other comprehensive income	(58)	(12)
Other comprehensive income, net of tax	1,722	2,717
Ending balance	(12,420)	829
Defined Benefit Pension Plans
Components of accumulated other comprehensive income (loss), net of related tax benefit/expense
Beginning balance	(25,894)	(27,144)
Other comprehensive income before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income	349	(375)
Other comprehensive income, net of tax	349	(375)
Ending balance	(25,545)	(27,519)
Total
Components of accumulated other comprehensive income (loss), net of related tax benefit/expense
Beginning balance	(40,036)	(29,032)
Ending balance	$ (37,965)	$ (26,690)

Accumulated Other Comprehens103

Accumulated Other Comprehensive Loss - Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain on sale of investment securities	$ 90	$ 19
Income tax (expense)/benefit	(12,257)	(9,757)
Net income	47,604	23,605
Net Income (Loss)	349	375
Gains and losses on available-for-sale securities | Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain on sale of investment securities	90	19
Income tax (expense)/benefit	(32)	(7)
Net income	58	12
Amortization of defined benefit pension plan items
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries, wages and employee benefits (operating expenses)	537	577
Income tax (expense)/benefit	$ (188)	$ (202)