First Interstate BancSystem (FIBK) 10-Q 8 Nov 16 2016 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	9 Months Ended
	Sep. 30, 2016shares
Entity Registrant Name	FIRST INTERSTATE BANCSYSTEM INC
Entity Central Index Key	860,413
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Amendment Flag	false
Class A Common Stock
Entity Common Stock, Shares Outstanding	21,459,481
Class B Common Stock
Entity Common Stock, Shares Outstanding	23,420,517

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets
Cash and due from banks	$ 148,690	$ 132,595
Federal funds sold	2,146	563
Interest bearing deposits in banks	550,531	647,299
Total cash and cash equivalents	701,367	780,457
Investment securities:
Available-for-sale	1,533,221	1,456,840
Held-to-maturity (estimated fair values of $554,048 and $607,550 at September 30, 2016 and December 31, 2015, respectively)	539,052	600,665
Total investment securities	2,072,273	2,057,505
Loans held for investment	5,462,936	5,193,321
Mortgage loans held for sale	67,979	52,875
Total loans	5,530,915	5,246,196
Less allowance for loan losses	81,235	76,817
Net loans	5,449,680	5,169,379
Goodwill	212,820	204,523
Premises and equipment, net of accumulated depreciation	191,064	190,812
Company-owned life insurance	197,070	187,253
Other real estate owned (OREO)	9,447	6,254
Accrued interest receivable	31,002	27,729
Core deposit intangibles, net of accumulated amortization	10,546	10,589
Mortgage servicing rights, net of accumulated amortization and impairment reserve	17,322	15,621
Other assets	81,256	78,074
Total assets	8,973,847	8,728,196
Deposits:
Non-interest bearing	1,965,872	1,823,716
Interest bearing	5,362,709	5,265,221
Total deposits	7,328,581	7,088,937
Securities sold under repurchase agreements	476,768	510,635
Accounts payable and accrued expenses	55,050	53,042
Accrued interest payable	5,622	4,960
Deferred tax liability	14,888	9,765
Long-term debt	27,949	27,885
Other borrowed funds	8	2
Subordinated debentures held by subsidiary trusts	82,477	82,477
Total liabilities	7,991,343	7,777,703
Stockholders' equity:
Nonvoting noncumulative preferred stock without par value; authorized 100,000 shares; no shares issued and outstanding as of September 30, 2016 or December 31, 2015	0	0
Common stock	293,960	311,720
Retained earnings	679,722	638,367
Accumulated other comprehensive income, net	8,822	406
Total stockholders' equity	982,504	950,493
Total liabilities and stockholders' equity	$ 8,973,847	$ 8,728,196

Consolidated Balance Sheets (U3

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Investment securities:
Held-to-Maturity, Estimated Fair Value	$ 554,048	$ 607,550
Stockholders' equity:
Nonvoting noncumulative preferred stock, par value	$ 0	$ 0
Nonvoting noncumulative preferred stock, authorized shares	100,000	100,000
Nonvoting noncumulative preferred stock, issued shares	0	0
Nonvoting noncumulative preferred stock, outstanding shares	0	0

Consolidated Statements of Inco

Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Interest income:
Interest and fees on loans	$ 65,626	$ 62,062	$ 191,076	$ 181,835
Interest and dividends on investment securities:
Taxable	7,878	7,410	23,898	23,381
Exempt from federal taxes	820	962	2,557	3,061
Interest on deposits in banks	607	342	1,734	1,002
Interest on federal funds sold	4	4	9	11
Total interest income	74,935	70,780	219,274	209,290
Interest expense:
Interest on deposits	3,099	3,241	9,435	9,789
Interest on securities sold under repurchase agreements	100	55	282	162
Interest on long-term debt	457	544	1,357	1,596
Interest on subordinated debentures held by subsidiary trusts	698	610	2,036	1,800
Total interest expense	4,354	4,450	13,110	13,347
Net interest income	70,581	66,330	206,164	195,943
Provision for loan losses	2,363	1,098	8,913	3,533
Net interest income after provision for loan losses	68,218	65,232	197,251	192,410
Non-interest income:
Payment services revenues	9,019	8,574	25,658	24,383
Income from the origination and sale of loans	8,013	7,983	20,347	22,691
Investment Advisory, Management and Administrative Fees	4,995	5,233	14,736	15,067
Service charges on deposit accounts	4,692	4,379	13,781	12,376
Other service charges, commissions and fees	2,628	2,521	8,081	7,752
Investment securities gains, net	225	23	312	75
Other income	2,299	2,465	7,049	8,515
Non-recurring litigation recovery	0	0	3,750	0
Total non-interest income	31,871	31,178	93,714	90,859
Non-interest expense:
Salaries and wages	23,618	25,460	71,791	76,902
Employee benefits	8,610	8,008	26,285	23,987
Outsourced technology services	5,211	2,520	14,843	7,576
Occupancy, net	4,413	4,413	13,361	13,434
Furniture and equipment	2,398	3,849	7,114	11,345
OREO expense, net of income	8	(720)	109	(1,604)
Professional fees	1,191	1,916	3,635	4,731
FDIC insurance premiums	1,212	1,190	3,668	3,636
Mortgage servicing rights amortization	854	617	2,210	1,863
Mortgage servicing rights impairment recovery	(16)	(76)	(21)	(147)
Core deposit intangibles amortization	875	842	2,529	2,551
Other expenses	12,542	12,613	36,740	37,994
Loss Contingency, Loss in Period	0	5,000	0	5,000
Non-core acquisition expenses	1,197	566	1,197	629
Total non-interest expense	62,113	66,198	183,461	187,897
Income before income tax expense	37,976	30,212	107,504	95,372
Income tax expense	12,783	10,050	36,633	32,008
Net income	$ 25,193	$ 20,162	$ 70,871	$ 63,364
Basic earnings per common share	$ 0.57	$ 0.45	$ 1.59	$ 1.40
Diluted earnings per common share	$ 0.56	$ 0.44	$ 1.58	$ 1.39

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Net income	$ 25,193	$ 20,162	$ 70,871	$ 63,364
Other comprehensive income (loss), before tax:
Change in net unrealized gains/losses during period	(3,430)	10,855	15,241	12,264
Reclassification adjustment for net (gains) losses included in income	(225)	(23)	(312)	(75)
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	490	448	1,394	1,353
Unrealized loss on derivatives	512	(436)	(2,490)	(436)
Defined benefit post-retirement benefits plans:
Change in net actuarial loss	15	15	43	43
Other comprehensive income (loss), before tax	(2,638)	10,859	13,876	13,149
Deferred tax benefit (expense) related to other comprehensive income	1,038	(4,273)	(5,460)	(5,174)
Other comprehensive income (loss), net of tax	(1,600)	6,586	8,416	7,975
Comprehensive income, net of tax	$ 23,593	$ 26,748	$ 79,287	$ 71,339

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders Equity (Unaudited) - USD ($) $ in Thousands	Total	Common stock	Retained earnings	Accumulated other comprehensive income
Beginning Balance at Dec. 31, 2014	$ 908,924	$ 323,596	$ 587,862	$ (2,534)
Comprehensive income:
Net income	63,364	0	63,364	0
Other comprehensive income, net of tax	7,975	0	0	7,975
Common stock transactions:
Common shares purchased and retired 998,135 and 789,743 in 2016 and 2015, respectively	(20,548)	(20,548)	0	0
Stock Issued During Period, 16,085 and 21,414 in 2016 and 2015, respectively	0	0	0	0
Non-vested common shares issued 189,624 and 169,577 in 2016 and 2015 respectively	0	0	0	0
25,984 and 3,484 non-vested common shares forfeited in 2016 and 2015 respectively	0	0	0	0
270,183 and 158,828 stock options exercised, net of 94,902 and 58,996 shares tendered in payment of option price and income tax withholding amounts in 2016 and 2015 respectively	1,909	1,909	0	0
Tax benefit of stock-based compensation	979	979	0	0
Stock-based compensation expense	3,231	3,231	0	0
Cash dividends declared:
Common ($0.66 per share) in 2016 and ($0.60 per share) in 2015	(27,259)	0	(27,259)	0
Ending Balance at Sep. 30, 2015	938,575	309,167	623,967	5,441
Beginning Balance at Dec. 31, 2015	950,493	311,720	638,367	406
Comprehensive income:
Net income	70,871	0	70,871	0
Other comprehensive income, net of tax	8,416	0	0	8,416
Common stock transactions:
Common shares purchased and retired 998,135 and 789,743 in 2016 and 2015, respectively	(26,119)	(26,119)	0	0
Stock Issued During Period, 16,085 and 21,414 in 2016 and 2015, respectively	0	0	0	0
Non-vested common shares issued 189,624 and 169,577 in 2016 and 2015 respectively	0	0	0	0
25,984 and 3,484 non-vested common shares forfeited in 2016 and 2015 respectively	0	0	0	0
270,183 and 158,828 stock options exercised, net of 94,902 and 58,996 shares tendered in payment of option price and income tax withholding amounts in 2016 and 2015 respectively	3,657	3,657	0	0
Tax benefit of stock-based compensation	1,352	1,352	0	0
Stock-based compensation expense	3,350	3,350	0	0
Cash dividends declared:
Common ($0.66 per share) in 2016 and ($0.60 per share) in 2015	(29,516)	0	(29,516)	0
Ending Balance at Sep. 30, 2016	$ 982,504	$ 293,960	$ 679,722	$ 8,822

Consolidated Statements of Cha7

Consolidated Statements of Changes in Stockholders Equity (Unaudited) (Parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Common stock
Common stock transactions:
Common shares purchased and retired	998,135	789,743
Common shares issued	16,085	21,414
Non-vested common shares issued	189,624	169,577
Non-vested common shares forfeited	25,984	3,484
Stock options exercised	270,183	217,824
Shares tendered in payment of option price and income tax withholding amounts	94,902	58,996
Retained earnings
Cash dividends declared:
Common (in dollars per share)	$ 0.66	$ 0.60

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 70,871	$ 63,364
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	8,913	3,533
Net (gain) loss on disposal of property and equipment	492	(822)
Depreciation and amortization	14,482	13,702
Net premium amortization on investment securities	9,423	11,527
Net gains on investment securities transactions	(312)	(75)
Net gains on sales of mortgage loans held for sale	(15,126)	(16,397)
Net gain on sale of OREO	(693)	(2,862)
Write-downs of OREO and other assets pending disposal	621	985
Net reversal of impairment of mortgage servicing rights	(21)	(147)
Deferred income tax expense	(344)	12,975
Net increase in cash surrender value of company-owned life insurance policies	(3,431)	(2,169)
Stock-based compensation expense	3,350	3,231
Tax benefits from stock-based compensation expense	1,352	979
Excess tax benefits from stock-based compensation	(1,126)	(884)
Originations of loans held for sale	(799,445)	(856,384)
Proceeds from sales of loans held for sale	795,527	865,833
Changes in operating assets and liabilities:
Increase in interest receivable	(2,203)	(3,962)
Increase in other assets	(2,644)	(4,766)
Decrease in accrued interest payable	646	(639)
Decrease in accounts payable and accrued expenses	(1,278)	(17,583)
Net cash provided by operating activities	79,054	69,439
Cash flows from investing activities:
Purchases of held-to-maturity investment securities	(18,170)	(28,745)
Purchases of available-for-sale investment securities	(626,574)	(253,049)
Proceeds from maturities and paydowns of held-to-maturity investment securities	86,306	80,759
Proceeds from maturities and paydowns of available-for-sale investment securities	652,064	450,462
Purchases of company-owned life insurance	0	30,000
Extensions of credit to customers, net of repayments	(203,216)	(251,450)
Recoveries of loans charged-off	6,363	4,439
Proceeds from sales of OREO	3,352	13,586
Acquisition of banks and bank holding companies, net of cash and cash equivalents received	(18,554)	1,636
Proceeds from sale of loan production office	932	0
Capital expenditures, net of sales	(5,113)	(2,236)
Net cash used in investing activities	(85,502)	(17,870)
Cash flows from financing activities:
Net increase (decrease) in deposits	30,057	(33,983)
Net increase (decrease) in repurchase agreements	(51,917)	(66,717)
Net increase (decrease) in other borrowed funds	6	1
Repayments of long-term debt	(49)	(1,297)
Advances on long-term debt	113	5,066
Proceeds from issuance of common stock	3,657	1,909
Excess tax benefits from stock-based compensation	1,126	884
Purchase and retirement of common stock	(26,119)	(20,548)
Dividends paid to common stockholders	(29,516)	(27,259)
Net cash provided by (used in) financing activities	(72,642)	(141,944)
Net increase (decrease) in cash and cash equivalents	(79,090)	(90,375)
Cash and cash equivalents at beginning of period	780,457	798,670
Cash and cash equivalents at end of period	701,367	708,295
Supplemental disclosures of cash flow information:
Cash paid during the period for income taxes	40,416	27,335
Cash paid during the period for interest expense	12,448	13,853
Transfer of loans to loans held for sale	50	10,619
Transfer of loans to other real estate owned	5,335	5,380
Capitalization of internally originated mortgage servicing rights	3,890	2,709
Transfer of bank buildings and land pending disposal to other assets	$ 0	$ 1,805

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	In the opinion of management, the accompanying unaudited consolidated financial statements of First Interstate BancSystem, Inc. and subsidiaries (the “Company”) contain all adjustments (all of which are of a normal recurring nature) necessary to present fairly the financial position of the Company at September 30, 2016 and December 31, 2015 , the results of operations for each of the three and nine month periods ended September 30, 2016 and 2015 , and cash flows and changes in stockholders' equity for each of the nine month periods ended September 30, 2016 and 2015 , in conformity with U.S. generally accepted accounting principles. The balance sheet information at December 31, 2015 is derived from audited consolidated financial statements. Certain reclassifications, none of which were material, have been made to conform prior year financial statements to the September 30, 2016 presentation. These reclassifications did not change previously reported net income or stockholders’ equity. These unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015 . Operating results for the three and nine months ended September 30, 2016 are not necessarily indicative of the results that may be expected for the year ending December 31, 2016 .

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Acquisitions	Acquisitions Flathead Bank. On April 6, 2016 , the Company's bank subsidiary, First Interstate Bank ("FIB"), entered into a stock purchase agreement to acquire all of the outstanding stock of Flathead Bank of Bigfork ("Flathead"), a Montana-based bank wholly owned by Flathead Holding Company. The acquisition was completed as of August 12, 2016 for cash consideration of $ 34,100 . The acquisition allowed the Company to gain market share in several of its current market areas and expand its market presence in Montana. The Company also benefited from cost savings related to the merger of Flathead with FIB. The acquisition was accounted for using the acquisition method with the cash purchase price funded from cash on hand. In conjunction with the acquisition, the Company recognized acquisition costs of $ 1,197 . The assets and liabilities of Flathead were recorded in the Company's consolidated financial statements at their estimated fair values as of the acquisition date. The excess value of the consideration paid over the fair value of assets acquired and liabilities assumed is recorded as goodwill. Goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of Flathead and the Company. The following table summarizes the consideration paid, fair values of the Flathead assets acquired and liabilities assumed and the resulting goodwill. All amounts reported are provisional pending completion of management review. As Recorded Fair Value As Recorded As of August 12, 2016 by Flathead Adjustments by the Company Assets acquired: Cash and cash equivalents $ 52,653 $ — $ 52,653 Investment securities 99,801 1,315 (1) 101,116 Loans 87,181 (3,833 ) (2) 83,348 Allowance for loan losses (1,567 ) 1,567 (3) — Premises and equipment 4,529 891 (4) 5,420 Core deposit intangible assets — 2,486 (5) 2,486 Company-owned life insurance 6,386 — 6,386 Other assets 5,200 (2,373 ) (6) 2,827 Total assets acquired 254,183 53 254,236 Liabilities assumed: Deposits 209,673 (86 ) (7) 209,587 Repurchase agreements 18,050 — 18,050 Other liabilities 838 — 838 Total liabilities assumed 228,561 (86 ) 228,475 Net assets acquired $ 25,622 $ 139 25,761 Cash consideration paid 34,100 Goodwill $ 8,339 Explanation of fair value adjustments: (1) Write up of the book value of investments to their estimated fair values on the date of acquisition based upon quotes obtained from an independent third party pricing service. (2) Write down of the book value of loans to their estimated fair values. The fair value of loans was estimated using cash flow projections based on the remaining maturity and repricing terms, adjusted for estimated future credit losses and prepayments and discounted to present value using a risk-adjusted market rate for similar loans. The fair value of collateral dependent loans acquired with deteriorated credit quality was estimated based on the Company's analysis of the fair value of each loan's underlying collateral, discounted using market-derived rates of return with consideration given to the period of time and costs associated with foreclosure and disposition of the collateral. (3) Adjustment to remove the Flathead allowance for loan losses at acquisition date as the credit risk is accounted for in the fair value adjustment for loans receivable described in (2) above. (4) Write up of the book value of premises and equipment to their estimated fair values on the date of acquisition based upon appraisals obtained from an independent third party appraiser or pending buy/sell agreements. (5) Adjustment represents the value of the core deposit base assumed in the acquisition based upon an internal valuation using industry averages obtained from an investment banking firm. (6) Adjustment consists of the write-off of pre-existing goodwill and prepaid assets. (7) Decrease in book value of time deposits to their estimated fair values based upon interest rates of similar time deposits with similar terms on the date of acquisition. The core deposit intangible asset of $ 2,486 is being amortized using an accelerated method over the estimated useful lives of the related deposits of nine years. The Company acquired certain loans that are subject to Accounting Standards Codification ("ASC") Topic 310-30 "Loans and Debt Securities Acquired with Deteriorated Credit Quality." ASC Topic 310-30 provides recognition, measurement and disclosure guidance for acquired loans that have evidence of deterioration in credit quality since origination for which it is probable, at acquisition, the Company will be unable to collect all contractual amounts owed. For loans that meet the criteria stipulated in ASC Topic 310-30, the excess of all cash flows expected at acquisition over the initial fair value of the loans acquired ("accretable yield") is amortized to interest income over the expected remaining lives of the underlying loans using the effective interest method. The accretable yield will fluctuate due to changes in (i) estimated lives of underling credit-impaired loans, (ii) assumptions regarding future principal and interest amounts collected, and (iii) indices used to fair value variable rate loans. Information regarding acquired credit-impaired loans as of the August 12, 2016 acquisition date is as follows: Contractually required principal and interest payments $ 19,324 Contractual cash flows not expected to be collected ("non-accretable discount") 10,999 Cash flows expected to be collected 8,325 Interest component of cash flows expected to be collected ("accretable discount") 1,113 Fair value of acquired credit-impaired loans $ 7,212 Information regarding acquired loans not deemed credit-impaired at the acquisition date is as follows: Contractually required principal and interest payments $ 100,616 Contractual cash flows not expected to be collected 4,702 Fair value at acquisition 76,136 The accompanying consolidated statements of income include the results of operations of the acquired entity from the August 12, 2016 acquisition date. Operations of the acquired entity were immediately integrated with the Company's operations. Post-acquisition revenues and net income of the acquired entity were not captured separately subsequent to the merger. As such, the Company has determined it is not practical to report the post-acquisition date revenues and net income of the acquired entity that were included in the Company's consolidated income statement for the three months and nine months ended September 30, 2016 . The following table presents unaudited pro forma consolidated revenues and net income as if the acquisition had occurred as of January 1, 2015. Three months ended September 30, Nine months ended September 30, 2016 2015 2016 2015 Interest income $ 75,736 $ 72,605 $ 223,547 $ 207,425 Non-interest income 32,114 31,647 95,011 91,218 Total revenues $ 107,850 $ 104,252 $ 318,558 $ 298,643 Net income $ 26,207 $ 20,783 $ 72,844 $ 64,545 The unaudited pro forma net income presented in the table above for 2016 was adjusted to exclude acquisition-related costs, including change in control expenses related to employee benefit plans and legal and professional expenses of $ 778 , net of tax. Pro forma net income presented in the table above for 2015 was adjusted to include the aforementioned acquisition-related costs. The unaudited pro forma net income presented in the table above for 2016 and 2015 includes adjustments for scheduled amortization of core deposit intangible assets acquired in the acquisition. The unaudited pro forma net income presented in the table above for 2016 and 2015 does not include operating costs savings and other business synergies expected as a result of the acquisition and adjustments for accretion or amortization of fair value adjustments other than core deposit intangible assets. Absarokee Bancorporation, Inc. On July 24, 2015 , the Company acquired all of the outstanding stock of Absarokee Bancorporation, Inc. ("Absarokee"), a Montana-based bank holding company that operated one subsidiary bank, United Bank. The Company merged United Bank with and into FIB immediately subsequent to the acquisition. During March 2016 , the Company completed its review of Absarokee's tax items and finalized the fair value of the acquired deferred tax asset. Finalization of provisional estimates resulted in a $ 42 decrease in goodwill.

Investment Securities

Investment Securities	9 Months Ended
	Sep. 30, 2016
Investments, Debt and Equity Securities [Abstract]
Investment Securities	he amortized cost and approximate fair values of investment securities are summarized as follows: September 30, 2016 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: U.S. Treasury notes $ 3,609 $ 30 $ — $ 3,639 Obligations of U.S. government agencies 439,488 1,819 (180 ) 441,127 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 1,063,642 20,088 (361 ) 1,083,369 Private mortgage-backed securities 124 1 (1 ) 124 Other investments 4,920 42 — 4,962 Total $ 1,511,783 $ 21,980 $ (542 ) $ 1,533,221 September 30, 2016 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 165,891 $ 6,048 $ (30 ) $ 171,909 Corporate securities 53,146 614 (14 ) 53,746 Obligations of U.S. government agencies 19,737 315 — 20,052 U.S agency residential mortgage-backed securities & collateralized mortgage obligations 300,018 14,643 (6,581 ) 308,080 Other investments 260 1 — 261 Total $ 539,052 $ 21,621 $ (6,625 ) $ 554,048 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: U.S. Treasury notes $ 3,912 $ 3 $ (4 ) $ 3,911 Obligations of U.S. government agencies 521,079 712 (1,610 ) 520,181 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 921,699 9,448 (2,101 ) 929,046 Private mortgage-backed securities 156 1 (1 ) 156 Other investments 3,550 5 (9 ) 3,546 Total $ 1,450,396 $ 10,169 $ (3,725 ) $ 1,456,840 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 173,785 $ 5,103 $ (227 ) $ 178,661 Corporate securities 50,046 64 (220 ) 49,890 Obligations of U.S. government agencies 19,738 — (102 ) 19,636 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 356,742 7,686 (5,420 ) 359,008 Other investments 354 1 — 355 Total $ 600,665 $ 12,854 $ (5,969 ) $ 607,550 Gross realized gains and losses from the disposition of investment securities are summarized in the following table: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Gross realized gains $ 239 $ 23 $ 404 $ 75 Gross realized losses (14 ) — (92 ) — On October 30, 2015 , the Company transferred available-for-sale U.S. agency residential mortgage-backed securities and collateralized mortgage obligations with amortized costs and fair values of $ 100,343 and $ 100,140 , respectively, into the held-to-maturity category. Unrealized net losses of $ 203 included in accumulated other comprehensive income at the time of the transfer are being amortized to yield over the remaining expected lives of the transferred securities of 4.0 years . On June 27, 2014 , the Company transferred available-for-sale U.S. agency residential mortgage-backed securities and collateralized mortgage obligations with amortized costs and fair values of $ 396,640 and $ 388,808 , respectively, into the held-to-maturity category. Unrealized net losses of $ 7,832 at the time of the transfer are being amortized to yield over the remaining expected lives of the transferred securities of 4.3 years . The following tables show the gross unrealized losses and fair values of investment securities, aggregated by investment category, and the length of time individual investment securities have been in a continuous unrealized loss position, as of September 30, 2016 and December 31, 2015 : Less than 12 Months 12 Months or More Total September 30, 2016 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: Obligations of U.S. government agencies $ — $ — $ 103,776 $ (180 ) $ 103,776 $ (180 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 83,050 (222 ) 17,419 (139 ) 100,469 (361 ) Private mortgage-backed securities — — 50 (1 ) 50 (1 ) Total $ 83,050 $ (222 ) $ 121,245 $ (320 ) $ 204,295 $ (542 ) Less than 12 Months 12 Months or More Total September 30, 2016 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 7,746 $ (24 ) $ 2,843 $ (6 ) $ 10,589 $ (30 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 8,791 (2,721 ) 18,523 (3,860 ) 27,314 (6,581 ) Corporate securities 5,056 (14 ) — — 5,056 (14 ) Total $ 21,593 $ (2,759 ) $ 21,366 $ (3,866 ) $ 42,959 $ (6,625 ) Less than 12 Months 12 Months or More Total December 31, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: U.S. Treasury notes $ 2,092 $ (4 ) $ — $ — $ 2,092 $ (4 ) Obligations of U.S. government agencies 209,631 (1,077 ) 54,619 (533 ) 264,250 (1,610 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 343,875 (1,577 ) 28,010 (524 ) 371,885 (2,101 ) Private mortgage-backed securities — — 61 (1 ) 61 (1 ) Other investments 1,225 (9 ) — — 1,225 (9 ) Total $ 556,823 $ (2,667 ) $ 82,690 $ (1,058 ) $ 639,513 $ (3,725 ) Less than 12 Months 12 Months or More Total December 31, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 10,182 $ (39 ) $ 9,476 $ (188 ) $ 19,658 $ (227 ) Obligations of U.S. government agencies 19,738 (102 ) — — 19,738 (102 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 67,295 (4,288 ) 69,539 (1,132 ) 136,834 (5,420 ) Corporate securities 31,135 (220 ) — — 31,135 (220 ) Total $ 128,350 $ (4,649 ) $ 79,015 $ (1,320 ) $ 207,365 $ (5,969 ) The investment portfolio is evaluated quarterly for other-than-temporary declines in the market value of each individual investment security. The Company had 126 and 198 individual investment securities that were in an unrealized loss position as of September 30, 2016 and December 31, 2015 , respectively. As of September 30, 2016 , the Company had the intent and ability to hold these investment securities for a period of time sufficient to allow for an anticipated recovery. Furthermore, the Company does not have the intent to sell any of the available-for-sale securities in the above table and it is more likely than not that the Company will not have to sell any securities before a recovery in cost. No impairment losses were recorded during three or nine months ended September 30, 2016 and 2015 . Maturities of investment securities at September 30, 2016 are shown below. Maturities of mortgage-backed securities have been adjusted to reflect shorter maturities based upon estimated prepayments of principal. All other investment securities maturities are shown at contractual maturity dates. Available-for-Sale Held-to-Maturity September 30, 2016 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Within one year $ 340,072 $ 345,636 $ 99,864 $ 97,362 After one year but within five years 1,030,847 1,045,108 290,601 304,804 After five years but within ten years 108,831 109,852 117,829 121,191 After ten years 32,033 32,625 30,758 30,691 Total $ 1,511,783 $ 1,533,221 $ 539,052 $ 554,048 As of September 30, 2016 , the Company had investment securities callable within one year with amortized costs and estimated fair values of $ 220,907 and $ 221,189 , respectively. These investment securities are primarily included in the after one year but within five years category in the table above. As of September 30, 2016 , the Company had callable structured notes with amortized costs and estimated fair values of $ 10,095 and $10,100 , respectively.

Loans

Loans	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Loans	Loans The following table presents loans by class as of the dates indicated: September 30, December 31, Real estate loans: Commercial $ 1,843,120 $ 1,793,258 Construction: Land acquisition & development 212,680 224,066 Residential 137,014 111,763 Commercial 128,154 94,890 Total construction loans 477,848 430,719 Residential 1,047,150 1,032,851 Agricultural 172,949 156,234 Total real estate loans 3,541,067 3,413,062 Consumer: Indirect consumer 731,901 622,529 Other consumer 153,624 153,717 Credit card 66,860 68,107 Total consumer loans 952,385 844,353 Commercial 814,392 792,416 Agricultural 152,800 142,151 Other, including overdrafts 2,292 1,339 Loans held for investment 5,462,936 5,193,321 Mortgage loans held for sale 67,979 52,875 Total loans $ 5,530,915 $ 5,246,196 Loans are considered past due if the required principal and interest payments have not been received as of the date such payments were due. The following tables present the contractual aging of the Company’s recorded investment in past due loans by class as of the dates indicated: Total Loans 30 - 59 60 - 89 > 90 30 or More Days Days Days Days Current Non-accrual Total As of September 30, 2016 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 8,023 $ 484 $ 727 $ 9,234 $ 1,806,929 $ 26,957 $ 1,843,120 Construction: Land acquisition & development 500 424 50 974 206,388 5,318 212,680 Residential 592 — 237 829 135,919 266 137,014 Commercial 3,375 57 — 3,432 123,905 817 128,154 Total construction loans 4,467 481 287 5,235 466,212 6,401 477,848 Residential 4,019 1,870 2,837 8,726 1,035,626 2,798 1,047,150 Agricultural 10 — 830 840 168,773 3,336 172,949 Total real estate loans 16,519 2,835 4,681 24,035 3,477,540 39,492 3,541,067 Consumer: Indirect consumer 5,707 1,735 622 8,064 723,048 789 731,901 Other consumer 1,029 329 20 1,378 151,886 360 153,624 Credit card 711 261 565 1,537 65,323 — 66,860 Total consumer loans 7,447 2,325 1,207 10,979 940,257 1,149 952,385 Commercial 2,366 640 1,915 4,921 782,378 27,093 814,392 Agricultural 219 88 17 324 148,741 3,735 152,800 Other, including overdrafts — — 311 311 1,981 — 2,292 Loans held for investment 26,551 5,888 8,131 40,570 5,350,897 71,469 5,462,936 Mortgage loans originated for sale — — — — 67,979 — 67,979 Total loans $ 26,551 $ 5,888 $ 8,131 $ 40,570 $ 5,418,876 $ 71,469 $ 5,530,915 Total Loans 30 - 59 60 - 89 > 90 30 or More Days Days Days Days Current Non-accrual Total As of December 31, 2015 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 6,051 $ 724 $ 418 $ 7,193 $ 1,762,294 $ 23,771 $ 1,793,258 Construction: Land acquisition & development 3,190 163 1,325 4,678 212,757 6,631 224,066 Residential 1,288 — — 1,288 110,182 293 111,763 Commercial 3,232 — — 3,232 90,703 955 94,890 Total construction loans 7,710 163 1,325 9,198 413,642 7,879 430,719 Residential 5,991 1,196 2,063 9,250 1,018,359 5,242 1,032,851 Agricultural 176 17 — 193 150,686 5,355 156,234 Total real estate loans 19,928 2,100 3,806 25,834 3,344,981 42,247 3,413,062 Consumer: Indirect consumer 6,675 1,089 210 7,974 614,029 526 622,529 Other consumer 1,312 331 34 1,677 151,381 659 153,717 Credit card 533 317 477 1,327 66,768 12 68,107 Total consumer loans 8,520 1,737 721 10,978 832,178 1,197 844,353 Commercial 8,493 1,060 699 10,252 759,851 22,313 792,416 Agricultural 879 152 62 1,093 140,430 628 142,151 Other, including overdrafts — — 314 314 1,025 — 1,339 Loans held for investment 37,820 5,049 5,602 48,471 5,078,465 66,385 5,193,321 Mortgage loans originated for sale — — — — 52,875 — 52,875 Total loans $ 37,820 $ 5,049 $ 5,602 $ 48,471 $ 5,131,340 $ 66,385 $ 5,246,196 Loans from business combinations included in the tables above include certain loans that had evidence of deterioration in credit quality since origination and for which it was probable, at acquisition, that all contractually required payments would not be collected. The following table displays the outstanding unpaid principal balance, accrued interest receivable and accrual status of loans acquired with credit impairment as of September 30, 2016 and 2015 : As of September 30, 2016 2015 Outstanding balance $ 38,505 $ 35,265 Carrying value Loans on accrual status 23,665 22,867 Total carrying value $ 23,665 $ 22,867 The following table summarizes changes in the accretable yield for loans acquired credit impaired for the three and nine months ended September 30, 2016 and 2015 : Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Beginning balance $ 5,905 $ 7,482 $ 6,713 $ 5,781 Additions 1,114 624 1,114 1,073 Accretion income (670 ) (845 ) (1,899 ) (2,200 ) Reductions due to exit events (595 ) (143 ) (900 ) (539 ) Reclassifications from nonaccretable differences 729 347 1,455 3,350 Ending balance $ 6,483 $ 7,465 $ 6,483 $ 7,465 Acquired loans that met the criteria for nonaccrual of interest prior to acquisition were considered performing upon acquisition. If interest on non-accrual loans had been accrued, such income would have been approximately $ 820 and $ 828 for the three months ended September 30, 2016 and 2015 , respectively, and approximately $2,492 and $2,331 for the nine months ended September 30, 2016 and 2015 respectively. The Company considers impaired loans to include all originated and acquired loans, except consumer loans, that are risk rated as doubtful, or have been placed on non-accrual status or renegotiated in troubled debt restructurings. The following tables present information on the Company’s recorded investment in impaired loans as of dates indicated: As of September 30, 2016 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 58,137 $ 16,518 $ 29,451 $ 45,969 $ 5,868 Construction: Land acquisition & development 12,922 4,774 1,785 6,559 828 Residential 977 266 — 266 — Commercial 1,154 232 703 935 737 Total construction loans 15,053 5,272 2,488 7,760 1,565 Residential 5,229 2,774 1,043 3,817 142 Agricultural 3,988 3,646 26 3,672 1 Total real estate loans 82,407 28,210 33,008 61,218 7,576 Commercial 39,349 15,296 18,893 34,189 10,912 Agricultural 3,925 3,294 441 3,735 77 Total $ 125,681 $ 46,800 $ 52,342 $ 99,142 $ 18,565 As of December 31, 2015 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 58,179 $ 27,882 $ 17,614 $ 45,496 $ 3,401 Construction: Land acquisition & development 15,503 7,245 778 8,023 282 Residential 992 293 — 293 — Commercial 1,264 340 739 1,079 739 Total construction loans 17,759 7,878 1,517 9,395 1,021 Residential 7,073 3,547 2,317 5,864 367 Agricultural 6,434 5,563 198 5,761 5 Total real estate loans 89,445 44,870 21,646 66,516 4,794 Commercial 29,593 10,744 13,727 24,471 6,487 Agricultural 1,349 622 356 978 294 Total $ 120,387 $ 56,236 $ 35,729 $ 91,965 $ 11,575 The following table presents the average recorded investment in and income recognized on impaired loans for the periods indicated: Three Months Ended September 30, 2016 2015 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 33,408 $ 100 $ 36,075 $ 226 Construction: Land acquisition & development 6,797 13 9,325 29 Residential 274 — 330 — Commercial 1,055 1 2,339 4 Total construction loans 8,126 14 11,994 33 Residential 3,282 4 2,607 4 Agricultural 4,786 2 8,578 27 Total real estate loans 49,602 120 59,254 290 Commercial 30,123 72 22,483 2 Agricultural 2,249 — 937 13 Total $ 81,974 $ 192 $ 82,674 $ 305 Nine Months Ended September 30, 2016 2015 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 35,572 $ 241 $ 38,639 $ 587 Construction: Land acquisition & development 6,992 32 9,591 51 Residential 279 — 300 — Commercial 1,007 3 1,902 6 Total construction loans 8,278 35 11,793 57 Residential 4,219 7 2,720 6 Agricultural 4,607 3 8,661 62 Total real estate loans 52,676 286 61,813 712 Commercial 27,781 128 18,175 122 Agricultural 2,341 — 848 26 Total $ 82,798 $ 414 $ 80,836 $ 860 The amount of interest income recognized by the Company within the period that the loans were impaired was primarily related to loans modified in a troubled debt restructuring that remained on accrual status. Interest payments received on non-accrual impaired loans are applied to principal. Interest income is subsequently recognized only to the extent cash payments are received in excess of principal due. If interest on impaired loans had been accrued, interest income on impaired loans would have been approximately $ 993 and $ 998 for the three months ended September 30, 2016 and 2015 , respectively, and approximately $2,994 and $2,932 for the nine months ended September 30, 2016 and 2015, respectively. Collateralized impaired loans are generally recorded at the fair value of the underlying collateral using discounted cash flows, independent appraisals and management estimates based upon current market conditions. For loans measured under the present value of cash flows method, the change in present value attributable to the passage of time, if applicable, is recognized in the provision for loan losses and thus no interest income is recognized. Modifications of performing loans are made in the ordinary course of business and are completed on a case-by-case basis as negotiated with the borrower. Loan modifications typically include interest rate concessions, interest only periods of less than twelve months, short-term payment deferrals and extension of amortization periods to provide payment relief. A loan modification is considered a troubled debt restructuring if the borrower is experiencing financial difficulties and the Company, for economic or legal reasons, grants a concession to the borrower that it would not otherwise consider. Certain troubled debt restructurings are on non-accrual status at the time of restructuring and are typically returned to accrual status after considering the borrower's sustained repayment performance in accordance with the restructuring agreement for a period of at least six months and management is reasonably assured of future performance. If the troubled debt restructuring meets these performance criteria and the interest rate granted at the modification is equal to or greater than the rate that the Company was willing to accept at the time of the restructuring for a new loan with comparable risk, then the loan will return to performing status and the accrual of interest will resume. The Company had loans renegotiated in troubled debt restructurings of $ 44,704 as of September 30, 2016 , of which $ 27,541 were included in non-accrual loans and $ 17,163 were on accrual status. The Company had loans renegotiated in troubled debt restructurings of $ 40,330 as of December 31, 2015 , of which $ 24,911 were included in non-accrual loans and $ 15,419 were on accrual status. The following table presents information on the Company's troubled debt restructurings that occurred during the three and nine months ended September 30, 2016 : Number of Notes Type of Concession Principal Balance at Restructure Date Three Months Ended September 30, 2016 Interest only period Extension of terms or maturity Interest rate adjustment Other (1) Commercial real estate 4 $ — $ 841 $ — $ 983 $ 1,824 Residential real estate 1 — 64 — — 64 Agriculture 1 — 121 — — 121 Total loans restructured during period 6 $ — $ 1,026 $ — $ 983 $ 2,009 Number of Notes Type of Concession Principal Balance at Restructure Date Nine Months Ended September 30, 2016 Interest only period Extension of terms or maturity Interest rate adjustment Other (1) Commercial real estate 11 $ 689 $ 1,166 $ — $ 1,233 $ 3,088 Residential real estate 1 — 64 — — 64 Commercial 10 4,240 947 46 2,805 8,038 Agriculture 1 — 121 — — 121 Total loans restructured during period 23 $ 4,929 $ 2,298 $ 46 $ 4,038 $ 11,311 (1) Other includes concessions that reduce or defer payments for a specified period of time and/or do not fit into other designated categories. For troubled debt restructurings that were on non-accrual status or otherwise deemed impaired before the modification, a specific reserve may already be recorded. In periods subsequent to modification, the Company continues to evaluate all troubled debt restructurings for possible impairment and recognizes impairment through the allowance. Additionally these loans continue to work their way through the credit cycle through charge-off, pay-off or foreclosure. Financial effects of modifications of troubled debt restructurings may include principal loan forgiveness or other charge-offs directly related to the restructuring. The Company had no charge-offs directly related to modifying troubled debt restructurings during the three and nine months ended September 30, 2016 or 2015 . The following table presents information on the Company's troubled debt restructurings during the previous 12 months for which there was a payment default during the three and nine months ended September 30, 2016 . The Company considers a payment default to occur on troubled debt restructurings when the loan is 90 days or more past due or was placed on non-accrual status after the modification. Three Months Ended September 30, 2016 Nine Months Ended September 30, 2016 Number of Notes Balance Number of Notes Balance Commercial real estate — $ — 1 $ 194 Total — $ — 1 $ 194 At September 30, 2016 , there were no material commitments to lend additional funds to borrowers whose existing loans have been renegotiated or are classified as non-accrual. As part of the on-going and continuous monitoring of the credit quality of the Company’s loan portfolio, management tracks internally assigned risk classifications of loans. The Company adheres to a Uniform Classification System developed jointly by the various bank regulatory agencies to internally risk rate loans. The Uniform Classification System defines three broad categories of criticized assets, which the Company uses as credit quality indicators: Other Assets Especially Mentioned — includes loans that exhibit weaknesses in financial condition, loan structure or documentation, which if not promptly corrected, may lead to the development of abnormal risk elements. Substandard — includes loans that are inadequately protected by the current sound worth and paying capacity of the borrower. Although the primary source of repayment for a substandard loan is not currently sufficient, collateral or other sources of repayment are sufficient to satisfy the debt. Continuance of a substandard loan is not warranted unless positive steps are taken to improve the worthiness of the credit. Doubtful — includes loans that exhibit pronounced weaknesses to a point where collection or liquidation in full, on the basis of currently existing facts, conditions and values, is highly questionable and improbable. Doubtful loans are required to be placed on non-accrual status and are assigned specific loss exposure. Company management undertakes the same process for assigning risk ratings to acquired loans as it does for originated loans. Acquired loans rated as substandard or lower or that were on non-accrual status or designated as troubled debt restructurings at the time of acquisition are deemed to be acquired credit impaired loans accounted for under ASC Topic 310-30, regardless of whether they are classified as performing or non-performing loans. The following tables present the Company’s recorded investment in criticized loans by class and credit quality indicator based on the most recent analysis performed as of the dates indicated: As of September 30, 2016 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 76,913 $ 88,580 $ 17,991 $ 183,484 Construction: Land acquisition & development 11,597 7,377 1,383 20,357 Residential 1,615 1,482 664 3,761 Commercial 1,616 5,891 720 8,227 Total construction loans 14,828 14,750 2,767 32,345 Residential 5,461 13,195 214 18,870 Agricultural 6,511 16,605 — 23,116 Total real estate loans 103,713 133,130 20,972 257,815 Consumer: Indirect consumer 847 1,572 121 2,540 Other consumer 665 1,130 217 2,012 Total consumer loans 1,512 2,702 338 4,552 Commercial 42,080 31,931 19,758 93,769 Agricultural 5,563 7,792 472 13,827 Total $ 152,868 $ 175,555 $ 41,540 $ 369,963 As of December 31, 2015 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 61,787 $ 84,556 $ 10,609 $ 156,952 Construction: Land acquisition & development 16,593 12,482 591 29,666 Residential 1,640 1,886 — 3,526 Commercial 166 323 756 1,245 Total construction loans 18,399 14,691 1,347 34,437 Residential 4,453 9,661 2,540 16,654 Agricultural 6,114 16,529 — 22,643 Total real estate loans 90,753 125,437 14,496 230,686 Consumer: Indirect consumer 644 1,131 154 1,929 Other consumer 651 1,130 198 1,979 Total consumer loans 1,295 2,261 352 3,908 Commercial 32,975 27,982 15,085 76,042 Agricultural 2,247 7,105 417 9,769 Total $ 127,270 $ 162,785 $ 30,350 $ 320,405 The Company maintains a credit review function, which is independent of the credit approval process, to assess assigned internal risk classifications and monitor compliance with internal lending policies and procedures. Written action plans with firm target dates for resolution of identified problems are maintained and reviewed on a quarterly basis for all categories of criticized loans.

Allowance For Loan Losses

Allowance For Loan Losses	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Allowance For Loan Losses	The following tables present a summary of changes in the allowance for loan losses by portfolio segment for the periods indicated: Three Months Ended September 30, 2016 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 32,281 $ 6,315 $ 39,995 $ 1,749 $ — $ 80,340 Provision charged to operating expense (352 ) 2,395 265 55 — 2,363 Less loans charged-off (379 ) (2,157 ) (579 ) — — (3,115 ) Add back recoveries of loans previously charged-off 221 742 680 4 — 1,647 Ending balance $ 31,771 $ 7,295 $ 40,361 $ 1,808 $ — $ 81,235 Nine Months Ended September 30, 2016 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 52,296 $ 5,144 $ 18,775 $ 602 $ — $ 76,817 Provision charged to operating expense (20,492 ) 5,747 22,268 1,390 — 8,913 Less loans charged-off (2,824 ) (5,761 ) (2,085 ) (188 ) — (10,858 ) Add back recoveries of loans previously charged-off 2,791 2,165 1,403 4 — 6,363 Ending balance $ 31,771 $ 7,295 $ 40,361 $ 1,808 $ — $ 81,235 As of September 30, 2016 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 7,576 $ — $ 10,912 $ 77 $ — $ 18,565 Loans collectively evaluated for impairment 24,195 7,295 29,449 1,731 — 62,670 Allowance for loan losses $ 31,771 $ 7,295 $ 40,361 $ 1,808 $ — $ 81,235 Total loans: Individually evaluated for impairment $ 61,218 $ — $ 34,189 $ 3,735 $ — $ 99,142 Collectively evaluated for impairment 3,479,849 952,385 780,203 149,065 2,292 5,363,794 Total loans $ 3,541,067 $ 952,385 $ 814,392 $ 152,800 $ 2,292 $ 5,462,936 Three Months Ended September 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 Provision charged to operating expense (1,149 ) 430 2,004 (187 ) — 1,098 Less loans charged-off (2,219 ) (1,537 ) (791 ) — — (4,547 ) Add back recoveries of loans previously charged-off 389 653 111 — — 1,153 Ending balance $ 50,956 $ 5,374 $ 17,121 $ 805 $ — $ 74,256 Nine Months Ended September 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 53,884 $ 5,035 $ 14,307 $ 974 $ — $ 74,200 Provision charged to operating expense (1,718 ) 2,201 3,220 (170 ) — 3,533 Less loans charged-off (3,014 ) (3,675 ) (1,227 ) — — (7,916 ) Add back recoveries of loans previously charged-off 1,804 1,813 821 1 — 4,439 Ending balance $ 50,956 $ 5,374 $ 17,121 $ 805 $ — $ 74,256 As of December 31, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 4,794 $ — $ 6,487 $ 294 $ — $ 11,575 Loans collectively evaluated for impairment 47,502 5,144 12,288 308 — 65,242 Allowance for loan losses $ 52,296 $ 5,144 $ 18,775 $ 602 $ — $ 76,817 Total loans: Individually evaluated for impairment $ 66,516 $ — $ 24,471 $ 978 $ — $ 91,965 Collectively evaluated for impairment 3,346,546 844,353 767,945 141,173 1,339 5,101,356 Total loans $ 3,413,062 $ 844,353 $ 792,416 $ 142,151 $ 1,339 $ 5,193,321 The Company performs a quarterly assessment of the adequacy of its allowance for loan losses in accordance with generally accepted accounting principles. The methodology used to assess the adequacy is consistently applied to the Company's loan portfolio and consists of three elements: (1) specific valuation allowances based on probable losses on impaired loans; (2) historical valuation allowances based on loan loss experience for similar loans with similar characteristics and trends; and (3) general valuation allowances determined based on changes in the nature of the loan portfolio, overall portfolio quality, industry concentrations, delinquency trends, general economic conditions and other qualitative risk factors both internal and external to the Company. Specific allowances are established for loans where management has determined that probability of a loss exists by analyzing the borrower’s ability to repay amounts owed, collateral deficiencies and any relevant qualitative or economic factors impacting the loan. Historical valuation allowances are determined by applying percentage loss factors to the credit exposures from outstanding loans. For commercial, agricultural and real estate loans, loss factors are applied based on the internal risk classifications of these loans. For consumer loans, loss factors are applied on a portfolio basis. For commercial, agriculture and real estate loans, loss factor percentages are based on a migration analysis of our historical loss experience, designed to account for credit deterioration. For consumer loans, loss factor percentages are based on a one-year loss history. General valuation allowances are determined by evaluating, on a quarterly basis, changes in the nature and volume of the loan portfolio, overall portfolio quality, industry concentrations, current economic and regulatory conditions and the estimated impact of these factors on historical loss rates. An allowance for loan losses is established for loans acquired credit impaired and for which the Company projects a decrease in the expected cash flows in periods subsequent to the acquisition of such loans. As of September 30, 2016 and December 31, 2015 , the Company's allowance for loan losses included $433 and $382 , respectively, related to loans acquired credit impaired.

OREO

OREO	9 Months Ended
	Sep. 30, 2016
Repossessed Assets [Abstract]
Other Real Estate Owned	Other Real Estate Owned Information with respect to the Company's other real estate owned follows: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Beginning balance $ 7,908 $ 11,773 $ 6,254 $ 13,554 OREO acquired through acquisition 1,120 — 1,120 — Additions 1,316 984 5,335 5,380 Valuation adjustments — (73 ) (603 ) (179 ) Dispositions (897 ) (4,653 ) (2,659 ) (10,724 ) Ending balance $ 9,447 $ 8,031 $ 9,447 $ 8,031 Foreclosed residential real estate properties of $ 2,730 and $1,686 were included in other real estate owned as of September 30, 2016 and December 31, 2015, respectively. The Company did not have any consumer mortgage loans collateralized by residential real estate property that were in the process of foreclosure as of September 30, 2016 or December 31, 2015.

Derivatives and Hedging

Derivatives and Hedging	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities Disclosure [Text Block]	Derivatives and Hedging Activities Interest Rate Swap Contracts Designated as Hedges. For asset and liability management purposes, the Company has entered into an interest rate swap contract to hedge against changes in forecasted cash flows due to interest rate exposures. The swap agreement is a derivative instrument and converts a portion of the Company’s forecasted variable rate debt to a fixed rate (i.e., cash flow hedge) over the payment term of the interest rate swap. The effective portion of the gain or loss on cash flow hedging instruments is initially reported as a component of other comprehensive income and subsequently reclassified into earnings in the same period during which the transaction affects earnings. The ineffective portion of the gain or loss on derivative instruments, if any, is recognized in earnings. The Company does not enter into interest rate swap agreements for trading or speculative purposes. On September 22, 2015 , the Company entered into an interest rate swap contract with a notional amount of $100,000 that was designated as a cash flow hedge. Under the terms of the interest rate swap contract, the Company pays a fixed interest rate of 1.94% and the counterparty pays to the Company a variable interest rate equal to the three-month LIBOR. No cash is exchanged until the effective date, which begins on September 15, 2017 and ends on September 15, 2020 . The Company designated the interest payments related to Federal Home Loan Bank borrowings as the cash flow hedge. The hedge was fully effective during the current period. As such, no amount of ineffectiveness was included in the Company's income statement for the three or nine months ended September 30, 2016 . The Company expects the hedge to remain highly effective during the remaining term of the interest rate swap. Non-Hedging Interest Rate Swap Contracts. The Company enters into certain interest rate swap contracts that are not designated as hedging instruments. These derivative contracts relate to transactions in which the Company enters into an interest rate swap with a customer while at the same time entering into an offsetting interest rate swap with a third party financial institution. Because the Company acts as an intermediary for the customer, changes in the fair value of the underlying derivative contracts for the most part offset each other and do not significantly impact the Company's results of operations. Interest Rate Lock Commitments and Forward Loan Sales Contracts. In the normal course of business, the Company enters into interest rate lock commitments to finance residential mortgage loans that are not designated as accounting hedges. These commitments, which contain fixed expiration dates, offer the borrower an interest rate guarantee provided the loan meets underwriting guidelines and closes within the timeframe established by the Company. Interest rate risk arises on these commitments and subsequently closed loans if interest rates change between the time of the interest rate lock and the delivery of the loan to the investor. Loan commitments related to residential mortgage loans intended to be sold are considered derivatives and are marked to market through earnings. In addition to the effects of the change in market interest rate, the fair value measurement of the derivative also contemplates the expected cash flows to be received from the counterparty from the future sale of the loan. The Company sells residential mortgage loans on either a best efforts or mandatory delivery basis. The Company mitigates the effect of the interest rate risk inherent in providing interest rate lock commitments by entering into forward loan sales contracts. During the interest rate lock commitment period, these forward loan sales contracts are marked to market through earnings and are not designated as accounting hedges. Exclusive of the fair value component associated with the projected cash flows from the loan delivery to the investor, the changes in fair value related to movements in market rates of the interest rate lock commitments and the forward loan sales contracts generally move in opposite directions, and the net impact of changes in these valuations on net income during the loan commitment period is generally inconsequential. When the loan is funded to the borrower, the interest rate lock commitment derivative expires and the Company records a loan held for sale. The forward loan sales contract acts as a hedge against the variability in cash to be received from the loan sale. The changes in measurement of the estimated fair values of the interest rate lock commitments and forward loan sales contracts are included in mortgage banking revenues in the accompanying consolidated statements of income. The notional amounts and estimated fair values of the Company's derivatives are presented in the following table. Fair value estimates are obtained from third parties and are based on pricing models. September 30, 2016 December 31, 2015 Notional Amount Estimated Fair Value Notional Amount Estimated Fair Value Derivative Assets (included in other assets on balance sheet): Derivatives designated as hedges: Interest rate swap contracts $ — $ — $ 100,000 $ 165 Non-hedging interest rate derivatives: Interest rate swap contracts 20,757 1,577 9,369 788 Interest rate lock commitments 92,847 2,590 — — Total derivative assets $ 113,604 $ 4,167 $ 109,369 $ 953 Derivative Liabilities (included in accounts payable and accrued expenses on balance sheet): Derivatives designated as hedges: Interest rate swap contracts $ 100,000 $ 2,325 $ — $ — Non-hedging interest rate derivatives: Interest rate swap contracts 20,757 1,701 9,369 829 Forward loan sales contracts 156,264 620 — — Total derivative liabilities $ 277,021 $ 4,646 $ 9,369 $ 829 The following table presents the pre-tax gains or losses related to derivative contracts that were recorded in accumulated other comprehensive income and other non-interest income in the Company's statements of income for the periods indicated: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Derivatives designated as hedges: Amount of gain (loss) recognized in other comprehensive income (effective portion) $ 512 $ (436 ) $ (2,490 ) $ (436 ) Non-hedging interest rate derivatives: Amount of loss recognized in other non-interest income (3 ) (31 ) (82 ) (48 ) Amount of net fee income recognized in other non-interest income — — 245 — Amount of net gains recognized in mortgage banking revenues 752 — 1,970 —

Capital Stock

Capital Stock	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Common Stock	Capital Stock The Company had 21,459,481 shares of Class A common stock and 23,420,517 shares of Class B common stock outstanding as of September 30, 2016 . The Company had 21,698,594 shares of Class A common stock and 23,729,631 shares of Class B common stock outstanding as of December 31, 2015 . During the nine months ended September 30, 2016 , the Company repurchased and retired 975,877 shares of its Class A common stock in open market transactions at an aggregate purchase price of $ 25,525 . During the nine months ended September 30, 2015 , the Company repurchased and retired 765,875 shares of its Class A common stock in open market transactions at an aggregate purchase price of $19,921 . All repurchases were made pursuant to stock repurchase programs approved by the Company's Board of Directors. Under the terms of the current stock repurchase program, the Company may repurchase up to an additional 24,123 shares of its Class A common stock. All other stock repurchases during the nine months ended September 30, 2016 and 2015 were redemptions of vested restricted shares tendered in lieu of cash for payment of income tax withholding amounts by participants in the Company's equity compensation plans.

Earnings per Common Share

Earnings per Common Share	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Earnings per Common Share	Earnings per Common Share Basic earnings per common share is calculated by dividing net income by the weighted average number of common shares outstanding during the period presented, excluding unvested restricted stock. Diluted earnings per share is calculated by dividing net income by the weighted average number of common shares determined for the basic earnings per share computation plus the dilutive effects of stock-based compensation using the treasury stock method. The following table sets forth the computation of basic and diluted earnings per share for the three and nine month periods ended September 30, 2016 and 2015 : Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Net income $ 25,193 $ 20,162 $ 70,871 $ 63,364 Weighted average common shares outstanding for basic earnings per share computation 44,415,213 45,150,104 44,505,544 45,223,988 Dilutive effects of stock-based compensation 390,708 428,874 379,368 481,636 Weighted average common shares outstanding for diluted earnings per common share computation 44,805,921 45,578,978 44,884,912 45,705,624 Basic earnings per common share $ 0.57 $ 0.45 $ 1.59 $ 1.40 Diluted earnings per common share $ 0.56 $ 0.44 $ 1.58 $ 1.39 Anti-dilutive unvested time restricted stock 135 5,884 95,886 5,884 The Company had 218,556 and 165,489 shares of unvested restricted stock as of September 30, 2016 and 2015 , respectively, that were not included in the computation of diluted earnings per common share because performance conditions for vesting had not been met.

Regulatory Capital

Regulatory Capital	9 Months Ended
	Sep. 30, 2016
Banking and Thrift [Abstract]
Regulatory Capital	Regulatory Capital On July 2, 2013, the Board of Governors of the Federal Reserve Bank issued a final rule implementing a revised regulatory capital framework for U.S. banks in accordance with the Basel III international accord, ("Basel III"). Basel III includes a more stringent definition of capital and introduces a new common equity tier 1, or CET1, capital requirement, sets forth a comprehensive methodology for calculating risk-weighted assets, introduces a conservation buffer and sets out minimum capital ratios and overall capital adequacy standards. Under Basel III, certain deductions and adjustments to regulatory capital began to phase in starting January 1, 2015 and will be fully implemented on January 1, 2018. The capital conservation buffer required under Basel III began to phase in starting January 1, 2016 and will be fully implemented on January 1, 2019. As of September 30, 2016 and December 31, 2015 , the Company exceeded all capital adequacy requirements to which it is subject. Actual capital amounts and ratios for the Company and its bank subsidiary, as of September 30, 2016 and December 31, 2015 are presented in the following tables: Actual Adequately Capitalized Basel III Phase-In Schedule Adequately Capitalized Basel III Fully Phased-In Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio Amount Ratio September 30, 2016 Total risk-based capital: Consolidated $ 962,182 14.9 % $ 558,157 8.6 % $ 679,495 10.5 % $ 647,138 10.0 % FIB 898,288 13.9 556,154 8.6 677,057 10.5 644,816 10.0 Tier 1 risk-based capital: Consolidated 877,285 13.6 428,729 6.6 550,068 8.5 517,711 8.0 FIB 817,678 12.7 427,191 6.6 548,094 8.5 515,853 8.0 Common equity tier 1 risk-based capital: Consolidated 797,285 12.3 331,658 5.1 452,997 7.0 420,640 6.5 FIB 817,678 12.7 330,468 5.1 451,371 7.0 419,131 6.5 Leverage capital ratio: Consolidated 877,285 10.2 343,228 4.0 343,228 4.0 429,035 5.0 FIB 817,678 9.5 342,629 4.0 342,629 4.0 428,286 5.0 Actual Adequately Capitalized Basel III Phase-In Schedule Adequately Capitalized Basel III Fully Phased-In Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio Amount Ratio December 31, 2015 Total risk-based capital: Consolidated $ 946,156 15.4 % $ 492,692 8.0 % $ 646,658 10.5 % $ 615,865 10.0 % FIB 882,504 14.4 490,866 8.0 644,262 10.5 613,582 10.0 Tier 1 risk-based capital: Consolidated 861,339 14.0 369,519 6.0 523,485 8.5 $ 492,692 8.0 FIB 805,805 13.1 368,149 6.0 521,545 8.5 490,866 8.0 Common equity tier 1 risk-based capital: Consolidated 781,339 12.7 277,139 4.5 431,105 7.0 $ 400,312 6.5 FIB 805,805 13.1 276,112 4.5 429,508 7.0 398,829 6.5 Leverage capital ratio: Consolidated 861,339 10.1 340,480 4.0 340,480 4.0 $ 425,600 5.0 FIB 805,805 9.5 339,316 4.0 339,316 4.0 424,145 5.0 (1) The ratios for the well capitalized requirement are only applicable to FIB. However, the Company manages its capital position as if the requirement applies to the consolidated entity and has presented the ratios as if they also applied on a consolidated basis.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies In the normal course of business, the Company is involved in various other claims and litigation. In the opinion of management, following consultation with legal counsel, the ultimate liability or disposition thereof of all other claims and litigation is not expected to have a material adverse effect on the consolidated financial condition, results of operations or liquidity of the Company. As of September 30, 2016 , the Company had a commitment under a forward starting interest rate swap contract with a notional amount of $ 100,000 . For additional information about the forward starting interest rate swap contract, see Note 7 — Derivatives and Hedging Activity. As of September 30, 2016 , the Company had commitments under construction contracts of $527 . Residential mortgage loans sold to investors in the secondary market are sold with varying recourse provisions. Essentially all of the loan sales agreements require the repurchase of a mortgage loan by the seller in situations such as breach of representation, warranty or covenant; untimely document delivery; false or misleading statements; failure to obtain certain certificates or insurance; unmarketability; etc. Certain loan sales agreements contain repurchase requirements based on payment-related defects that are defined in terms of the number of days or months since the purchase, the sequence number of the payment, and/or the number of days of payment delinquency. Based on the specific terms stated in the agreements, the Company had $ 2,912 of sold residential mortgage loans with recourse provisions still in effect as of September 30, 2016 .

Financial Instruments with Off-

Financial Instruments with Off-Balance Sheet Risk	9 Months Ended
	Sep. 30, 2016
Financial Instruments with Off-Balance Sheet Risk [Abstract]
Financial Instruments with Off-Balance Sheet Risk	Financial Instruments with Off-Balance Sheet Risk The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and standby letters of credit. Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the commitment contract. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. At September 30, 2016 , commitments to extend credit to existing and new borrowers approximated $ 1,604,619 , which included $ 545,399 on unused credit card lines and $ 419,638 with commitment maturities beyond one year. Standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. At September 30, 2016 , the Company had outstanding standby letters of credit of $ 54,424 . The estimated fair value of the obligation undertaken by the Company in issuing the standby letters of credit is included in other liabilities in the Company’s consolidated balance sheet.

Other Comprehensive Income

Other Comprehensive Income	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Other Comprehensive Income	Other Comprehensive Income/Loss The gross amounts of each component of other comprehensive income and the related tax effects are as follows: Pre-tax Tax Expense (Benefit) Net of Tax Three Months Ended September 30, 2016 2015 2016 2015 2016 2015 Investment securities available-for sale: Change in net unrealized gains during period $ (3,430 ) $ 10,855 $ (1,359 ) $ 4,272 $ (2,071 ) $ 6,583 Reclassification adjustment for net gains included in net income (225 ) (23 ) (89 ) (10 ) (136 ) (13 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 490 448 209 177 281 271 Unrealized loss on derivatives 512 (436 ) 195 (172 ) 317 (264 ) Defined benefits post-retirement benefit plan: Change in net actuarial loss 15 15 6 6 9 9 Total other comprehensive income (loss) $ (2,638 ) $ 10,859 $ (1,038 ) $ 4,273 $ (1,600 ) $ 6,586 Pre-tax Tax Expense (Benefit) Net of Tax Nine Months Ended September 30, 2016 2015 2016 2015 2016 2015 Investment securities available-for sale: Change in net unrealized gains during period $ 15,241 $ 12,264 $ 5,963 $ 4,827 $ 9,278 $ 7,437 Reclassification adjustment for net gains included in net income (312 ) (75 ) (123 ) (30 ) (189 ) (45 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 1,394 1,353 549 532 845 821 Unrealized loss on derivatives (2,490 ) (436 ) (946 ) (172 ) (1,544 ) (264 ) Defined benefits post-retirement benefit plan: Change in net actuarial loss 43 43 17 17 26 26 Total other comprehensive income $ 13,876 $ 13,149 $ 5,460 $ 5,174 $ 8,416 $ 7,975 The components of accumulated other comprehensive income, net of related tax effects, are as follows: September 30, December 31, Net unrealized gain on investment securities available-for-sale $ 10,618 $ 684 Net unrealized gain (loss) on derivatives (1,444 ) 100 Net actuarial loss on defined benefit post-retirement benefit plans (352 ) (378 ) Net accumulated other comprehensive income $ 8,822 $ 406

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There is a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The three levels of inputs that may be used to measure fair value are as follows: • Level 1 - Quoted prices in active markets for identical assets or liabilities • Level 2 - Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities • Level 3 - Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of of assets or liabilities The methodologies used by the Company in determining the fair values of each class of financial instruments are based primarily on the use of independent, market-based data to reflect a value that would be reasonably expected in an orderly transaction between market participants at the measurement date, and therefore are classified within Level 2 of the valuation hierarchy. There were no transfers between fair value hierarchy levels during the three or nine months ended September 30, 2016 and 2015 . Further details on the methods used to estimate the fair value of each class of financial instruments above are discussed below: Investment Securities Available-for-Sale . The Company obtains fair value measurements for investment securities from an independent pricing service. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the investment's terms and conditions, among other things. Vendors chosen by the Company are widely recognized vendors whose evaluations support the pricing functions of financial institutions, investment and mutual funds, and portfolio managers. If needed, a broker may be utilized to determine the reported fair value of investment securities. Loans Held for Sale. Fair value measurements for loans held for sale are obtained from an independent pricing service. The fair value measurements consider observable data that may include binding contracts or quotes or bids from third party investors as well as loan level pricing adjustments. Interest Rate Swap Contracts. Fair values for derivative interest rate swap contracts are based upon the estimated amounts to settle the contracts considering current interest rates and are calculated using discounted cash flows that are observable or that can be corroborated by observable market data. The inputs used to determine fair value include the 3 month LIBOR forward curve to estimate variable rate cash inflows and the federal funds effective swap rate to estimate the discount rate. The estimated variable rate cash inflows are compared to the fixed rate outflows and such difference is discounted to a present value to estimate the fair value of the interest rate swaps. The change in the value of derivative assets attributable to basis risk, or the risk that offsetting investments in a hedging strategy will not experience price changes in entirely opposite directions from each other, was not significant in the reported periods. The Company also obtains and compares the reasonableness of the pricing from an independent third party. Interest Rate Lock Commitments. Fair value measurements for interest rate lock commitments are obtained from an independent pricing service. The fair value measurements consider observable data that may include prices available from secondary market investors taking into consideration various characteristics of the loan, including the loan amount, interest rate, value of the servicing and loan to value ratio, among other things. Observable data is then adjusted to reflect changes in interest rates, the Company's estimated pull-through rate and estimated direct costs necessary to complete the commitment into a closed loan net of origination and processing fees collected from the borrower. Forward Loan Sales Contracts. The fair value measurements for forward loan sales contracts are obtained from an independent pricing service. The fair value measurements consider observable data that includes sales of similar loans. Deferred Compensation Plan Assets and Liabilities. The fair values of deferred compensation plan assets are based primarily on the use of independent, market-based data to reflect a value that would be reasonably expected in an orderly transaction between market participants at the measurement date. These investments are in the same funds and purchased in the same amounts as the participants’ selected investments, which represent the underlying liabilities to plan participants. Deferred compensation plan liabilities are recorded at amounts due to participants, based on the fair value of participants’ selected investments. Financial assets and financial liabilities measured at fair value on a recurring basis are as follows: Fair Value Measurements at Reporting Date Using As of September 30, 2016 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Investment securities available-for-sale: U.S. Treasury Notes $ 3,639 $ — $ 3,639 $ — Obligations of U.S. government agencies 441,127 — 441,127 — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 1,083,369 — 1,083,369 — Private mortgage-backed securities 124 — 124 — Other investments 4,962 — 4,962 — Loans held for sale 67,979 — 67,979 — Derivative assets: Interest rate swap contracts 1,577 — 1,577 — Interest rate lock commitments 2,590 — 2,590 — Derivative liabilities: Interest rate swap contracts 4,026 — 4,026 — Forward loan sale contracts 620 — 620 — Deferred compensation plan assets 10,534 — 10,534 — Deferred compensation plan liabilities 10,534 — 10,534 — Fair Value Measurements at Reporting Date Using As of December 31, 2015 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Investment securities available-for-sale: U.S. Treasury notes $ 3,911 $ — $ 3,911 $ — Obligations of U.S. government agencies 520,181 — 520,181 — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 929,046 — 929,046 — Private mortgage-backed securities 156 — 156 — Other investments 3,546 — 3,546 — Derivative assets: Interest rate swap contracts 953 — 953 — Derivative liabilities Interest rate swap contracts 829 — 829 — Deferred compensation plan assets 10,149 — 10,149 — Deferred compensation plan liabilities 10,149 — 10,149 — Additionally, from time to time, certain assets are measured at fair value on a non-recurring basis. Adjustments to fair value generally result from the application of lower-of-cost-or-market accounting or write-downs of individual assets due to impairment. The following table presents information about the Company’s assets and liabilities measured at fair value on a non-recurring basis: Fair Value Measurements at Reporting Date Using As of September 30, 2016 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Impaired loans $ 39,746 $ — $ — $ 39,746 Other real estate owned 2,808 — — 2,808 Long-lived assets to be disposed of by sale 1,506 — — 1,506 Fair Value Measurements at Reporting Date Using As of December 31, 2015 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Impaired loans $ 20,875 $ — $ — $ 20,875 Other real estate owned 1,789 — — 1,789 Long-lived assets to be disposed of by sale 1,506 — — 1,506 Impaired Loans. Collateralized impaired loans are reported at the fair value of the underlying collateral if repayment is expected solely from collateral. The impaired loans are reported at fair value through specific valuation allowance allocations. In addition, when it is determined that the fair value of an impaired loan is less than the recorded investment in the loan, the carrying value of the loan is adjusted to fair value through a charge to the allowance for loan losses. Collateral values are estimated using independent appraisals and management estimates of current market conditions. As of September 30, 2016 , certain impaired loans with a carrying value of $ 68,733 were reduced by specific valuation allowance allocations of $ 18,565 and partial loan charge-offs of $ 10,422 resulting in a reported fair value of $ 39,746 . As of December 31, 2015 , certain impaired loans with a carrying value of $ 42,679 were reduced by specific valuation allowance allocations of $ 11,575 and partial loan charge-offs of $ 10,229 resulting in a reported fair value of $ 20,875 . OREO. The fair values of OREO are estimated using independent appraisals and management estimates of current market conditions. Upon initial recognition, write-downs based on the foreclosed asset's fair value at foreclosure are reported through charges to the allowance for loan losses. Periodically, the fair value of foreclosed assets is remeasured with any subsequent write-downs charged to OREO expense in the period in which they are identified. Write-downs of $603 during the nine months ended September 30, 2016 included $550 directly related to receipt of updated appraisals and $ 53 based on management estimates of the current fair value of properties. Write downs of $179 during the nine months ended September 30, 2015 included $106 directly related to receipt of updated appraisals and $ 73 based on management estimates of the current fair value of properties. Long-lived Assets to be Disposed of by Sale. Long-lived assets to be disposed of by sale are carried at the lower of carrying value or fair value less estimated costs to sell. The fair values of long-lived assets to be disposed of by sale are based upon observable market data and management estimates of current market conditions. As of September 30, 2016 and December 31, 2015 , the Company had long-lived assets to be disposed of by sale with carrying values aggregating $2,363 that were reduced by write-downs of $857 resulting in an aggregate fair value of $1,506 . The following table presents additional quantitative information about assets measured at fair value on a non-recurring basis and for which the Company has utilized Level 3 inputs to determine fair values: Fair Value As of September 30, 2016 December 31, 2015 Valuation Technique Unobservable Inputs Range (Weighted Average) Impaired loans $ 39,746 $ 20,875 Appraisal Appraisal adjustment 0% - 53% (38%) Other real estate owned 2,808 1,789 Appraisal Appraisal adjustment 2% - 96% (19%) Long-lived assets to be disposed of by sale 1,506 1,506 Appraisal Appraisal adjustment 0% - 9% (6%) The Company is required to disclose the fair value of financial instruments for which it is practical to estimate fair value. The methodologies for estimating the fair value of financial instruments that are measured at fair value on a recurring or non-recurring basis are discussed above. The methodologies for estimating the fair value of other financial instruments are discussed below. For financial instruments bearing a variable interest rate where no credit risk exists, it is presumed that recorded book values are reasonable estimates of fair value. Financial Assets. Carrying values of cash, cash equivalents and accrued interest receivable approximate fair values due to the liquid and/or short-term nature of these instruments. Fair values for investment securities held-to-maturity are obtained from an independent pricing service, which considers observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the investment’s terms and conditions, among other things. Fair values of fixed rate loans and variable rate loans that reprice on an infrequent basis are estimated by discounting future cash flows using current interest rates at which similar loans with similar terms would be made to borrowers of similar credit quality. Carrying values of variable rate loans that reprice frequently, and with no change in credit risk, approximate the fair values of these instruments. Financial Liabilities. The fair values of demand deposits, savings accounts, securities sold under repurchase agreements and accrued interest payable are the amounts payable on demand at the reporting date. The fair values of fixed-maturity certificates of deposit are estimated using external market rates currently offered for deposits with similar remaining maturities. The fair values of derivative liabilities are obtained from an independent pricing service, which considers observable data that may include the three-month LIBOR forward curve, the federal funds effective swap rate and cash flows, among other things. The carrying values of the interest bearing demand notes to the United States Treasury are deemed an approximation of fair values due to the frequent repayment and repricing at market rates. The fixed and floating rate subordinated debentures, floating rate subordinated term loan, notes payable to the FHLB, fixed rate subordinated term debt, and capital lease obligation are estimated by discounting future cash flows using current rates for advances with similar characteristics. Commitments to Extend Credit and Standby Letters of Credit. The fair value of commitments to extend credit and standby letters of credit, based on fees currently charged to enter into similar agreements, is not significant. The estimated fair values of financial instruments that are reported in the Company's consolidated balance sheets, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, are as follows: Fair Value Measurements at Reporting Date Using As of September 30, 2016 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets: Cash and cash equivalents $ 701,367 $ 701,367 $ 701,367 $ — $ — Investment securities available-for-sale 1,533,221 1,533,221 — 1,533,221 — Investment securities held-to-maturity 539,052 554,048 — 554,048 — Accrued interest receivable 31,002 31,002 — 31,002 — Mortgage servicing rights, net 17,322 25,845 — 25,845 — Loans held for sale 67,979 67,979 — 67,979 — Net loans held for investment 5,462,936 5,321,409 — 5,281,663 39,746 Derivative assets 4,167 4,167 — 4,167 — Deferred compensation plan assets 10,534 10,534 — 10,534 — Total financial assets $ 8,367,580 $ 8,249,572 $ 701,367 $ 7,508,459 $ 39,746 Financial liabilities: Total deposits, excluding time deposits $ 6,235,993 $ 6,235,993 $ 6,235,993 $ — $ — Time deposits 1,092,588 1,090,434 — 1,090,434 — Securities sold under repurchase agreements 476,768 476,768 — 476,768 — Other borrowed funds 8 8 — 8 — Accrued interest payable 5,622 5,622 — 5,622 — Long-term debt 27,949 27,801 — 27,801 — Subordinated debentures held by subsidiary trusts 82,477 72,803 — 72,803 — Derivative liabilities 4,646 4,646 — 4,646 — Deferred compensation plan liabilities 10,534 10,534 — 10,534 — Total financial liabilities $ 7,936,585 $ 7,924,609 $ 6,235,993 $ 1,688,616 $ — Fair Value Measurements at Reporting Date Using As of December 31, 2015 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets: Cash and cash equivalents $ 780,457 $ 780,457 $ 780,457 $ — $ — Investment securities available-for-sale 1,456,840 1,456,840 — 1,456,840 — Investment securities held-to-maturity 600,665 607,550 — 607,550 — Accrued interest receivable 27,729 27,729 — 27,729 — Mortgage servicing rights, net 15,621 31,011 — 31,011 — Net loans 5,169,379 5,128,705 — 5,107,830 20,875 Derivative assets 953 953 — 953 — Deferred compensation plan assets 10,149 10,149 — 10,149 — Total financial assets $ 8,061,793 $ 8,043,394 $ 780,457 $ 7,242,062 $ 20,875 Financial liabilities: Total deposits, excluding time deposits $ 5,957,345 $ 5,975,345 $ 5,975,345 $ — $ — Time deposits 1,131,592 1,137,289 — 1,137,289 — Securities sold under repurchase agreements 510,635 510,635 — 510,635 — Other borrowed funds 2 2 — 2 — Accrued interest payable 4,960 4,960 — 4,960 — Long-term debt 27,885 27,622 — 27,622 — Subordinated debentures held by subsidiary trusts 82,477 74,969 — 74,969 — Derivative liabilities 829 829 — 829 — Deferred compensation plan liabilities 10,149 10,149 — 10,149 — Total financial liabilities $ 7,725,874 $ 7,741,800 $ 5,975,345 $ 1,766,455 $ —

Recent Authoritative Accounting

Recent Authoritative Accounting Guidance	9 Months Ended
	Sep. 30, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Authoritative Accounting Guidance	Recent Authoritative Accounting Guidance ASU 2014-09 "Revenue from Contracts with Customers." The amendments in Accounting Standards Update ("ASU") 2014-09 introduce a new five-step revenue recognition model in which an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 also requires disclosures sufficient to enable users to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers, including qualitative and quantitative disclosures about contracts with customers, significant judgments and changes in judgments, and assets recognized from the costs to obtain or fulfill a contract. ASU 2015-14, “Revenue from Contracts with Customers (Topic 606) – Deferral of the Effective Date" was released in August of 2015 deferring the effective date of 2014-09 for all entities by one year until January 1, 2018. The Company is evaluating the new guidance to determine the impact it will have on its consolidated financial statements, results of operations or liquidity. ASU 2014-12 "Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could be Achieved after the Requisite Service Period." ASU 2014-12 amends Accounting Standards Codification ("ASC") Topic 718, Compensation-Stock Compensation, to clarify that a performance target that affects the vesting of a share-based payment award and that could be achieved after the requisite service period should be treated as a performance condition that affects the vesting of the award. ASU 2014-12 further clarifies that the requisite service period ends when the employees can cease rendering service and still be eligible to vest in the award if the performance target is achieved. The Company adopted the amendments in ASU 2014-12 effective January 1, 2016. The adoption did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2014-16 "Determining Whether the Host Contract in a Hybrid Financial Instrument Issued in the Form of a Share is More Akin to Debt or to Equity." The amendments in ASU 2014-16 clarify that an entity should consider all relevant terms and features-including the embedded derivative feature being evaluated for bifurcation-in evaluating the nature of the host contract within a hybrid financial instrument. The amendments further clarify that no single term or feature would necessarily determine the economic characteristics and risk of the host contract. Rather, the nature of the host contract depends upon the economic characteristics and risk of the entire hybrid financial instrument. The Company adopted the amendments in ASU 2014-16 effective January 1, 2016. The adoption did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2015-02 "Amendments to the Consolidation Analysis." The amendments in ASU 2015-02 (i) modify the evaluation of whether limited partnerships and similar legal entities are variable interest entities or voting interest entities, (ii) eliminate the presumption that a general partner should consolidate a limited partnership, (iii) affect the consolidation analysis of reporting entities that are involved with variable interest entities, particularly those that have fee arrangements and related party relationships, and (iv) provide scope exceptions from consolidation guidance for reporting entities with interest in legal entities that are required to comply or operate in accordance with requirements of the Investment Company Act of 1940 for registered market funds. The Company adopted the amendments in ASU 2015-02 effective January 1, 2016. The adoption did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2015-03 "Simplifying the Presentation of Debt Issuance Costs." The amendments in ASU 2015-03 require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, rather than as a deferred charge. The guidance in ASU 2015-03 did not address presentation or subsequent measurement of debt issues costs related to line-of-credit arrangements. ASU 2015-15, “Interest – Imputation of Interest (Subtopic 835-30) – Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements, Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting," addresses this gap. ASU 2015-15 adds that the Securities and Exchange Commission (the "SEC") staff would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The Company adopted the amendments in ASU 2015-03 and ASU 2015-15 effective January 1, 2016. The adoption did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2015-05 "Intangibles-Goodwill and Other Internal-Use Software." The amendments in ASU 2015-05 provide guidance about whether a cloud computing arrangement includes a software license. Under the guidance in ASU 2015-05, if a cloud computing arrangement includes a software license, the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. The Company adopted the amendments in ASU 2015-05 effective January 1, 2016. The adoption did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2015-10 "Technical Corrections and Improvements." The amendments in ASU 2015-10 represent changes to clarify the codification, correct unintended application of guidance, or make minor improvements to the codification that are not expected to have a significant effect on current accounting practice or create a significant administrative cost to most entities. The Company adopted the amendments in ASU 2015-10 effective January 1, 2016. The adoption did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2015-16 "Business Combinations-Simplifying the Accounting for Measurement-Period Adjustments." The amendments in ASU 2015-16 eliminate the requirement to retrospectively account for adjustments made to provisional amounts recognized as part of a business combination. Under the amendments in ASU 2015-16, an acquirer must recognize adjustments to the provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. The amendments in ASU 2015-16 require that the acquirer record, in the same period’s financial statements, the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. The Company adopted the amendments in ASU 2015-16 effective January 1, 2016. The adoption did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2016-01 "Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Financial Liabilities." The amendments in ASU 2016-1, among other things, (i) require equity investments, with certain exceptions, to be measured at fair value with changes in fair value recognized in net income, (ii) simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment, (iii) eliminates the requirement for public business entities to disclose the methods and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost on the balance sheet, (iv) requires public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes, (v) requires an entity to present separately in other comprehensive income the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value in accordance with the fair value option for financial instruments, (vi) requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the accompanying notes to the financial statements and (viii) clarifies that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale investment securities. The amendments in ASU 2016-1 will be effective for the Company on January 1, 2018, and are not expected to have a significant impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2016-02 "Leases (Topic 842)." On February 25, 2016, the Financial Accounting Standards Board issued new lease accounting guidance in ASU No. 2016-02. Under the new guidance, lessees will be required to recognize a lease liability and a right of use asset for all leases (with the exception of short-term leases) at the commencement date of the lease and disclose key information about leasing arrangements. Accounting by lessors is largely unchanged. ASU 2016-02 will be effective for the Company on January 1, 2019 and will be applied using a modified retrospective approach. The Company is evaluating the new guidance to determine the impact ASU 2016-02 will have on its consolidated financial statements, results of operations or liquidity. ASU 2016-05 "Derivatives and Hedging (Topic 815): Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships." The amendments in ASU 2016-05 clarify that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument under ASC Topic 815 does not, in and of itself, require dedesignation of that hedging relationship provided that all other hedge accounting criteria continue to be met. The amendments in ASU 2016-05 will be effective for the Company on January 1, 2017, and are not expected to have a significant impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2016-07 "Investments - Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting." The amendments in ASU 2016-07 eliminate the requirement that when an investment qualified for use of the equity method as a result of an increase in the level of ownership interest or degree of influence, an investor must adjust the investments, results of operations and retained earnings retroactively on a step-by-step basis as if the equity method had been in effect during all previous periods hat the investment had been held. The amendments in ASU 2016-07 also simplify the transition to the equity method of accounting by eliminating retroactive adjustment of the investment when an investment qualifies for use of the equity method, among other things. The amendments in ASU 2016-07 will be effective for the Company on January 1, 2017, and are not expected to have a significant impact on on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2016-08 "Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net)." The amendments in ASU 2016-08 were issued to clarify certain principal versus agent considerations within the implementation guidance of ASC Topic 606, “Revenue from Contracts with Customers.” The effective date and transition of ASU 2016-08 is the same as the effective date and transition of ASU 2014-09, Revenue from Contracts with Customers (Topic 606), as discussed above. The Company is continuing to evaluate the new guidance to determine the impact it will have on its consolidated financial statements, results of operations or liquidity. ASU 2016-09 "Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting." Under the amendments in ASU 2016-09, all excess tax benefits and tax deficiencies related to share-based payment awards should be recognized as income tax expense or benefit in the income statement during the period in which they occur. Previously, such amounts were recorded in the pool of excess tax benefits included in additional paid-in capital, if such pool was available. Because excess tax benefits are no longer recognized in additional paid-in capital, the assumed proceeds from applying the treasury stock method when computing earnings per share should exclude the amount of excess tax benefits that would have previously been recognized in additional paid-in capital. Additionally, excess tax benefits should be classified along with other income tax cash flows as an operating activity rather than a financing activity, as was previously the case. The amendments in ASU 2016-09 also provide that an entity can make an entity-wide accounting policy election to either estimate the number of awards that are expected to vest (current GAAP) or account for forfeitures when they occur. The amendments in ASU 2016-09 change the threshold to qualify for equity classification to permit withholding up to the maximum statutory tax rates (rather than the minimum as was previously the case) in the applicable jurisdictions. The amendments in ASU 2016-09 will be effective for the Company on January 1, 2017, and are not expected to have a significant impact on impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU No. 2016-10 "Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing." The amendments in ASU 2016-10 were issued to clarify ASC Topic 606, “Revenue from Contracts with Customers” related to (i) identifying performance obligations; and (ii) the licensing implementation guidance. The effective date and transition of ASU 2016-10 is the same as the effective date and transition of ASU 2014-09, “Revenue from Contracts with Customers (Topic 606),” as discussed above. The Company is continuing to evaluate the new guidance to determine the impact it will have on its consolidated financial statements, results of operations and liquidity. ASU No. 2016-13 "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments." The amendments in ASU 2016-13 require a financial asset or group of financial assets measured at amortized cost basis to be presented on a company's financial statements at the net amount expected to be collected based on historical experience, current conditions and reasonable and supportable forecasts. ASU 2016-13 requires a company's income statement to reflect the measurement of credit losses for newly recognized financial assets as well as the expected increases or decreases of expected credit losses that have taken place during the period. The amendments in ASU 2016-13 require that the allowance for credit losses for purchased financial assets with a more-than-insignificant amount of credit deterioration since origination be measured at amortized cost basis with the initial allowance for credit losses added to the purchase price rather than being reported as a credit loss expense. ASU 2016-13 also requires that credit losses relating to available-for-sale debt securities be recorded through an allowance for credit losses. The amendments in ASU 2016-13 are effective for the Company for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The amendments will be applied through a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period. A prospective transition approach is required for debt securities for which other-than-temporary impairment was recognized before the effective date. Amounts previously recognized in accumulated other comprehensive income as of the date of adoption that relate to improvement in cash flows expected to be collected will continue to be accreted into income over the remaining life of the asset. Recoveries of amounts previously written off relating to improvements in cash flows after the date of adoption will be recorded in earnings when received. The Company is currently evaluating the new guidance to determine the impact it will have on its consolidated financial statements, results of operations and liquidity. ASU No. 2016-15 "Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments." The amendments in ASU 2016-15 are intended to reduce diversity in practice in how eight particular transactions are classified in the statement of cash flows. ASU 2016-15 is effective for interim and annual reporting periods beginning after December 15, 2017. Early adoption is permitted, provided that all of the amendments are adopted in the same period. Entities will be required to apply the guidance retrospectively. If it is impracticable to apply the guidance retrospectively for an issue, the amendments related to that issue would be applied prospectively. The amendments in ASU 2016-15 only affect the classification of certain items within the statement of cash flows, and are not expected to have a significant impact on impact on the Company’s consolidated financial statements, results of operations or liquidity.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2016
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Subsequent events have been evaluated for potential recognition and disclosure through the date financial statements were filed with the SEC. On October 21, 2016 , the Company declared a quarterly dividend to common shareholders of $ 0.22 per share, to be paid on November 14, 2016 to shareholders of record as of October 31, 2016 . No other events requiring recognition or disclosure were identified.

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	As Recorded Fair Value As Recorded As of August 12, 2016 by Flathead Adjustments by the Company Assets acquired: Cash and cash equivalents $ 52,653 $ — $ 52,653 Investment securities 99,801 1,315 (1) 101,116 Loans 87,181 (3,833 ) (2) 83,348 Allowance for loan losses (1,567 ) 1,567 (3) — Premises and equipment 4,529 891 (4) 5,420 Core deposit intangible assets — 2,486 (5) 2,486 Company-owned life insurance 6,386 — 6,386 Other assets 5,200 (2,373 ) (6) 2,827 Total assets acquired 254,183 53 254,236 Liabilities assumed: Deposits 209,673 (86 ) (7) 209,587 Repurchase agreements 18,050 — 18,050 Other liabilities 838 — 838 Total liabilities assumed 228,561 (86 ) 228,475 Net assets acquired $ 25,622 $ 139 25,761 Cash consideration paid 34,100 Goodwill $ 8,339 Explanation of fair value adjustments: (1) Write up of the book value of investments to their estimated fair values on the date of acquisition based upon quotes obtained from an independent third party pricing service. (2) Write down of the book value of loans to their estimated fair values. The fair value of loans was estimated using cash flow projections based on the remaining maturity and repricing terms, adjusted for estimated future credit losses and prepayments and discounted to present value using a risk-adjusted market rate for similar loans. The fair value of collateral dependent loans acquired with deteriorated credit quality was estimated based on the Company's analysis of the fair value of each loan's underlying collateral, discounted using market-derived rates of return with consideration given to the period of time and costs associated with foreclosure and disposition of the collateral. (3) Adjustment to remove the Flathead allowance for loan losses at acquisition date as the credit risk is accounted for in the fair value adjustment for loans receivable described in (2) above. (4) Write up of the book value of premises and equipment to their estimated fair values on the date of acquisition based upon appraisals obtained from an independent third party appraiser or pending buy/sell agreements. (5) Adjustment represents the value of the core deposit base assumed in the acquisition based upon an internal valuation using industry averages obtained from an investment banking firm. (6) Adjustment consists of the write-off of pre-existing goodwill and prepaid assets. (7) Decrease in book value of time deposits to their estimated fair values based upon interest rates of similar time deposits with similar terms on the date of acquisition.
Schedule of acquired loans with credit impairment	Contractually required principal and interest payments $ 19,324 Contractual cash flows not expected to be collected ("non-accretable discount") 10,999 Cash flows expected to be collected 8,325 Interest component of cash flows expected to be collected ("accretable discount") 1,113 Fair value of acquired credit-impaired loans $ 7,212 The following table displays the outstanding unpaid principal balance, accrued interest receivable and accrual status of loans acquired with credit impairment as of September 30, 2016 and 2015 : As of September 30, 2016 2015 Outstanding balance $ 38,505 $ 35,265 Carrying value Loans on accrual status 23,665 22,867 Total carrying value $ 23,665 $ 22,867 The following table summarizes changes in the accretable yield for loans acquired credit impaired for the three and nine months ended September 30, 2016 and 2015 : Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Beginning balance $ 5,905 $ 7,482 $ 6,713 $ 5,781 Additions 1,114 624 1,114 1,073 Accretion income (670 ) (845 ) (1,899 ) (2,200 ) Reductions due to exit events (595 ) (143 ) (900 ) (539 ) Reclassifications from nonaccretable differences 729 347 1,455 3,350 Ending balance $ 6,483 $ 7,465 $ 6,483 $ 7,465
Schedule of Acquired Loans not Deemed to Have Credit Impairment [Table Text Block]	Contractually required principal and interest payments $ 100,616 Contractual cash flows not expected to be collected 4,702 Fair value at acquisition 76,136
Business Acquisition, Pro Forma Information [Table Text Block]	Three months ended September 30, Nine months ended September 30, 2016 2015 2016 2015 Interest income $ 75,736 $ 72,605 $ 223,547 $ 207,425 Non-interest income 32,114 31,647 95,011 91,218 Total revenues $ 107,850 $ 104,252 $ 318,558 $ 298,643 Net income $ 26,207 $ 20,783 $ 72,844 $ 64,545

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2016
Investments, Debt and Equity Securities [Abstract]
Amortized Cost and Approximate Fair Values of Investment Securities	The amortized cost and approximate fair values of investment securities are summarized as follows: September 30, 2016 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: U.S. Treasury notes $ 3,609 $ 30 $ — $ 3,639 Obligations of U.S. government agencies 439,488 1,819 (180 ) 441,127 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 1,063,642 20,088 (361 ) 1,083,369 Private mortgage-backed securities 124 1 (1 ) 124 Other investments 4,920 42 — 4,962 Total $ 1,511,783 $ 21,980 $ (542 ) $ 1,533,221 September 30, 2016 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 165,891 $ 6,048 $ (30 ) $ 171,909 Corporate securities 53,146 614 (14 ) 53,746 Obligations of U.S. government agencies 19,737 315 — 20,052 U.S agency residential mortgage-backed securities & collateralized mortgage obligations 300,018 14,643 (6,581 ) 308,080 Other investments 260 1 — 261 Total $ 539,052 $ 21,621 $ (6,625 ) $ 554,048 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: U.S. Treasury notes $ 3,912 $ 3 $ (4 ) $ 3,911 Obligations of U.S. government agencies 521,079 712 (1,610 ) 520,181 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 921,699 9,448 (2,101 ) 929,046 Private mortgage-backed securities 156 1 (1 ) 156 Other investments 3,550 5 (9 ) 3,546 Total $ 1,450,396 $ 10,169 $ (3,725 ) $ 1,456,840 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 173,785 $ 5,103 $ (227 ) $ 178,661 Corporate securities 50,046 64 (220 ) 49,890 Obligations of U.S. government agencies 19,738 — (102 ) 19,636 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 356,742 7,686 (5,420 ) 359,008 Other investments 354 1 — 355 Total $ 600,665 $ 12,854 $ (5,969 ) $ 607,550
Realized Gains (Losses) on Investments	Gross realized gains and losses from the disposition of investment securities are summarized in the following table: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Gross realized gains $ 239 $ 23 $ 404 $ 75 Gross realized losses (14 ) — (92 ) —
Gross Unrealized Losses and Fair Values of Investment Securities	The following tables show the gross unrealized losses and fair values of investment securities, aggregated by investment category, and the length of time individual investment securities have been in a continuous unrealized loss position, as of September 30, 2016 and December 31, 2015 : Less than 12 Months 12 Months or More Total September 30, 2016 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: Obligations of U.S. government agencies $ — $ — $ 103,776 $ (180 ) $ 103,776 $ (180 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 83,050 (222 ) 17,419 (139 ) 100,469 (361 ) Private mortgage-backed securities — — 50 (1 ) 50 (1 ) Total $ 83,050 $ (222 ) $ 121,245 $ (320 ) $ 204,295 $ (542 ) Less than 12 Months 12 Months or More Total September 30, 2016 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 7,746 $ (24 ) $ 2,843 $ (6 ) $ 10,589 $ (30 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 8,791 (2,721 ) 18,523 (3,860 ) 27,314 (6,581 ) Corporate securities 5,056 (14 ) — — 5,056 (14 ) Total $ 21,593 $ (2,759 ) $ 21,366 $ (3,866 ) $ 42,959 $ (6,625 ) Less than 12 Months 12 Months or More Total December 31, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: U.S. Treasury notes $ 2,092 $ (4 ) $ — $ — $ 2,092 $ (4 ) Obligations of U.S. government agencies 209,631 (1,077 ) 54,619 (533 ) 264,250 (1,610 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 343,875 (1,577 ) 28,010 (524 ) 371,885 (2,101 ) Private mortgage-backed securities — — 61 (1 ) 61 (1 ) Other investments 1,225 (9 ) — — 1,225 (9 ) Total $ 556,823 $ (2,667 ) $ 82,690 $ (1,058 ) $ 639,513 $ (3,725 ) Less than 12 Months 12 Months or More Total December 31, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 10,182 $ (39 ) $ 9,476 $ (188 ) $ 19,658 $ (227 ) Obligations of U.S. government agencies 19,738 (102 ) — — 19,738 (102 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 67,295 (4,288 ) 69,539 (1,132 ) 136,834 (5,420 ) Corporate securities 31,135 (220 ) — — 31,135 (220 ) Total $ 128,350 $ (4,649 ) $ 79,015 $ (1,320 ) $ 207,365 $ (5,969 )
Maturities of Investment Securities	Maturities of investment securities at September 30, 2016 are shown below. Maturities of mortgage-backed securities have been adjusted to reflect shorter maturities based upon estimated prepayments of principal. All other investment securities maturities are shown at contractual maturity dates. Available-for-Sale Held-to-Maturity September 30, 2016 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Within one year $ 340,072 $ 345,636 $ 99,864 $ 97,362 After one year but within five years 1,030,847 1,045,108 290,601 304,804 After five years but within ten years 108,831 109,852 117,829 121,191 After ten years 32,033 32,625 30,758 30,691 Total $ 1,511,783 $ 1,533,221 $ 539,052 $ 554,048

Loans (Tables)

Loans (Tables)	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Schedule of Loans by Class	September 30, December 31, Real estate loans: Commercial $ 1,843,120 $ 1,793,258 Construction: Land acquisition & development 212,680 224,066 Residential 137,014 111,763 Commercial 128,154 94,890 Total construction loans 477,848 430,719 Residential 1,047,150 1,032,851 Agricultural 172,949 156,234 Total real estate loans 3,541,067 3,413,062 Consumer: Indirect consumer 731,901 622,529 Other consumer 153,624 153,717 Credit card 66,860 68,107 Total consumer loans 952,385 844,353 Commercial 814,392 792,416 Agricultural 152,800 142,151 Other, including overdrafts 2,292 1,339 Loans held for investment 5,462,936 5,193,321 Mortgage loans held for sale 67,979 52,875 Total loans $ 5,530,915 $ 5,246,196
Schedule of Recorded Investment in Past Due Loans by Class	The following tables present the contractual aging of the Company’s recorded investment in past due loans by class as of the dates indicated: Total Loans 30 - 59 60 - 89 > 90 30 or More Days Days Days Days Current Non-accrual Total As of September 30, 2016 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 8,023 $ 484 $ 727 $ 9,234 $ 1,806,929 $ 26,957 $ 1,843,120 Construction: Land acquisition & development 500 424 50 974 206,388 5,318 212,680 Residential 592 — 237 829 135,919 266 137,014 Commercial 3,375 57 — 3,432 123,905 817 128,154 Total construction loans 4,467 481 287 5,235 466,212 6,401 477,848 Residential 4,019 1,870 2,837 8,726 1,035,626 2,798 1,047,150 Agricultural 10 — 830 840 168,773 3,336 172,949 Total real estate loans 16,519 2,835 4,681 24,035 3,477,540 39,492 3,541,067 Consumer: Indirect consumer 5,707 1,735 622 8,064 723,048 789 731,901 Other consumer 1,029 329 20 1,378 151,886 360 153,624 Credit card 711 261 565 1,537 65,323 — 66,860 Total consumer loans 7,447 2,325 1,207 10,979 940,257 1,149 952,385 Commercial 2,366 640 1,915 4,921 782,378 27,093 814,392 Agricultural 219 88 17 324 148,741 3,735 152,800 Other, including overdrafts — — 311 311 1,981 — 2,292 Loans held for investment 26,551 5,888 8,131 40,570 5,350,897 71,469 5,462,936 Mortgage loans originated for sale — — — — 67,979 — 67,979 Total loans $ 26,551 $ 5,888 $ 8,131 $ 40,570 $ 5,418,876 $ 71,469 $ 5,530,915 Total Loans 30 - 59 60 - 89 > 90 30 or More Days Days Days Days Current Non-accrual Total As of December 31, 2015 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 6,051 $ 724 $ 418 $ 7,193 $ 1,762,294 $ 23,771 $ 1,793,258 Construction: Land acquisition & development 3,190 163 1,325 4,678 212,757 6,631 224,066 Residential 1,288 — — 1,288 110,182 293 111,763 Commercial 3,232 — — 3,232 90,703 955 94,890 Total construction loans 7,710 163 1,325 9,198 413,642 7,879 430,719 Residential 5,991 1,196 2,063 9,250 1,018,359 5,242 1,032,851 Agricultural 176 17 — 193 150,686 5,355 156,234 Total real estate loans 19,928 2,100 3,806 25,834 3,344,981 42,247 3,413,062 Consumer: Indirect consumer 6,675 1,089 210 7,974 614,029 526 622,529 Other consumer 1,312 331 34 1,677 151,381 659 153,717 Credit card 533 317 477 1,327 66,768 12 68,107 Total consumer loans 8,520 1,737 721 10,978 832,178 1,197 844,353 Commercial 8,493 1,060 699 10,252 759,851 22,313 792,416 Agricultural 879 152 62 1,093 140,430 628 142,151 Other, including overdrafts — — 314 314 1,025 — 1,339 Loans held for investment 37,820 5,049 5,602 48,471 5,078,465 66,385 5,193,321 Mortgage loans originated for sale — — — — 52,875 — 52,875 Total loans $ 37,820 $ 5,049 $ 5,602 $ 48,471 $ 5,131,340 $ 66,385 $ 5,246,196
Schedule of acquired loans with credit impairment	Contractually required principal and interest payments $ 19,324 Contractual cash flows not expected to be collected ("non-accretable discount") 10,999 Cash flows expected to be collected 8,325 Interest component of cash flows expected to be collected ("accretable discount") 1,113 Fair value of acquired credit-impaired loans $ 7,212 The following table displays the outstanding unpaid principal balance, accrued interest receivable and accrual status of loans acquired with credit impairment as of September 30, 2016 and 2015 : As of September 30, 2016 2015 Outstanding balance $ 38,505 $ 35,265 Carrying value Loans on accrual status 23,665 22,867 Total carrying value $ 23,665 $ 22,867 The following table summarizes changes in the accretable yield for loans acquired credit impaired for the three and nine months ended September 30, 2016 and 2015 : Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Beginning balance $ 5,905 $ 7,482 $ 6,713 $ 5,781 Additions 1,114 624 1,114 1,073 Accretion income (670 ) (845 ) (1,899 ) (2,200 ) Reductions due to exit events (595 ) (143 ) (900 ) (539 ) Reclassifications from nonaccretable differences 729 347 1,455 3,350 Ending balance $ 6,483 $ 7,465 $ 6,483 $ 7,465
Schedule of Recorded Investment in Impaired Loans	The following tables present information on the Company’s recorded investment in impaired loans as of dates indicated: As of September 30, 2016 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 58,137 $ 16,518 $ 29,451 $ 45,969 $ 5,868 Construction: Land acquisition & development 12,922 4,774 1,785 6,559 828 Residential 977 266 — 266 — Commercial 1,154 232 703 935 737 Total construction loans 15,053 5,272 2,488 7,760 1,565 Residential 5,229 2,774 1,043 3,817 142 Agricultural 3,988 3,646 26 3,672 1 Total real estate loans 82,407 28,210 33,008 61,218 7,576 Commercial 39,349 15,296 18,893 34,189 10,912 Agricultural 3,925 3,294 441 3,735 77 Total $ 125,681 $ 46,800 $ 52,342 $ 99,142 $ 18,565 As of December 31, 2015 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 58,179 $ 27,882 $ 17,614 $ 45,496 $ 3,401 Construction: Land acquisition & development 15,503 7,245 778 8,023 282 Residential 992 293 — 293 — Commercial 1,264 340 739 1,079 739 Total construction loans 17,759 7,878 1,517 9,395 1,021 Residential 7,073 3,547 2,317 5,864 367 Agricultural 6,434 5,563 198 5,761 5 Total real estate loans 89,445 44,870 21,646 66,516 4,794 Commercial 29,593 10,744 13,727 24,471 6,487 Agricultural 1,349 622 356 978 294 Total $ 120,387 $ 56,236 $ 35,729 $ 91,965 $ 11,575 The following table presents the average recorded investment in and income recognized on impaired loans for the periods indicated: Three Months Ended September 30, 2016 2015 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 33,408 $ 100 $ 36,075 $ 226 Construction: Land acquisition & development 6,797 13 9,325 29 Residential 274 — 330 — Commercial 1,055 1 2,339 4 Total construction loans 8,126 14 11,994 33 Residential 3,282 4 2,607 4 Agricultural 4,786 2 8,578 27 Total real estate loans 49,602 120 59,254 290 Commercial 30,123 72 22,483 2 Agricultural 2,249 — 937 13 Total $ 81,974 $ 192 $ 82,674 $ 305 Nine Months Ended September 30, 2016 2015 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 35,572 $ 241 $ 38,639 $ 587 Construction: Land acquisition & development 6,992 32 9,591 51 Residential 279 — 300 — Commercial 1,007 3 1,902 6 Total construction loans 8,278 35 11,793 57 Residential 4,219 7 2,720 6 Agricultural 4,607 3 8,661 62 Total real estate loans 52,676 286 61,813 712 Commercial 27,781 128 18,175 122 Agricultural 2,341 — 848 26 Total $ 82,798 $ 414 $ 80,836 $ 860
Schedule of Loans Renegotiated in Troubled Debt Restructurings	Number of Notes Type of Concession Principal Balance at Restructure Date Three Months Ended September 30, 2016 Interest only period Extension of terms or maturity Interest rate adjustment Other (1) Commercial real estate 4 $ — $ 841 $ — $ 983 $ 1,824 Residential real estate 1 — 64 — — 64 Agriculture 1 — 121 — — 121 Total loans restructured during period 6 $ — $ 1,026 $ — $ 983 $ 2,009 Number of Notes Type of Concession Principal Balance at Restructure Date Nine Months Ended September 30, 2016 Interest only period Extension of terms or maturity Interest rate adjustment Other (1) Commercial real estate 11 $ 689 $ 1,166 $ — $ 1,233 $ 3,088 Residential real estate 1 — 64 — — 64 Commercial 10 4,240 947 46 2,805 8,038 Agriculture 1 — 121 — — 121 Total loans restructured during period 23 $ 4,929 $ 2,298 $ 46 $ 4,038 $ 11,311 (1) Other includes concessions that reduce or defer payments for a specified period of time and/or do not fit into other designated categories. The Company considers a payment default to occur on troubled debt restructurings when the loan is 90 days or more past due or was placed on non-accrual status after the modification. Three Months Ended September 30, 2016 Nine Months Ended September 30, 2016 Number of Notes Balance Number of Notes Balance Commercial real estate — $ — 1 $ 194 Total — $ — 1 $ 194
Schedule of Recorded Investment in Criticized Loans by Class and Credit Quality Indicator	The following tables present the Company’s recorded investment in criticized loans by class and credit quality indicator based on the most recent analysis performed as of the dates indicated: As of September 30, 2016 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 76,913 $ 88,580 $ 17,991 $ 183,484 Construction: Land acquisition & development 11,597 7,377 1,383 20,357 Residential 1,615 1,482 664 3,761 Commercial 1,616 5,891 720 8,227 Total construction loans 14,828 14,750 2,767 32,345 Residential 5,461 13,195 214 18,870 Agricultural 6,511 16,605 — 23,116 Total real estate loans 103,713 133,130 20,972 257,815 Consumer: Indirect consumer 847 1,572 121 2,540 Other consumer 665 1,130 217 2,012 Total consumer loans 1,512 2,702 338 4,552 Commercial 42,080 31,931 19,758 93,769 Agricultural 5,563 7,792 472 13,827 Total $ 152,868 $ 175,555 $ 41,540 $ 369,963 As of December 31, 2015 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 61,787 $ 84,556 $ 10,609 $ 156,952 Construction: Land acquisition & development 16,593 12,482 591 29,666 Residential 1,640 1,886 — 3,526 Commercial 166 323 756 1,245 Total construction loans 18,399 14,691 1,347 34,437 Residential 4,453 9,661 2,540 16,654 Agricultural 6,114 16,529 — 22,643 Total real estate loans 90,753 125,437 14,496 230,686 Consumer: Indirect consumer 644 1,131 154 1,929 Other consumer 651 1,130 198 1,979 Total consumer loans 1,295 2,261 352 3,908 Commercial 32,975 27,982 15,085 76,042 Agricultural 2,247 7,105 417 9,769 Total $ 127,270 $ 162,785 $ 30,350 $ 320,405

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2016
Receivables [Abstract]
Schedule of Allowance for Loan Losses by Portfolio Segment	The following tables present a summary of changes in the allowance for loan losses by portfolio segment for the periods indicated: Three Months Ended September 30, 2016 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 32,281 $ 6,315 $ 39,995 $ 1,749 $ — $ 80,340 Provision charged to operating expense (352 ) 2,395 265 55 — 2,363 Less loans charged-off (379 ) (2,157 ) (579 ) — — (3,115 ) Add back recoveries of loans previously charged-off 221 742 680 4 — 1,647 Ending balance $ 31,771 $ 7,295 $ 40,361 $ 1,808 $ — $ 81,235 Nine Months Ended September 30, 2016 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 52,296 $ 5,144 $ 18,775 $ 602 $ — $ 76,817 Provision charged to operating expense (20,492 ) 5,747 22,268 1,390 — 8,913 Less loans charged-off (2,824 ) (5,761 ) (2,085 ) (188 ) — (10,858 ) Add back recoveries of loans previously charged-off 2,791 2,165 1,403 4 — 6,363 Ending balance $ 31,771 $ 7,295 $ 40,361 $ 1,808 $ — $ 81,235 As of September 30, 2016 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 7,576 $ — $ 10,912 $ 77 $ — $ 18,565 Loans collectively evaluated for impairment 24,195 7,295 29,449 1,731 — 62,670 Allowance for loan losses $ 31,771 $ 7,295 $ 40,361 $ 1,808 $ — $ 81,235 Total loans: Individually evaluated for impairment $ 61,218 $ — $ 34,189 $ 3,735 $ — $ 99,142 Collectively evaluated for impairment 3,479,849 952,385 780,203 149,065 2,292 5,363,794 Total loans $ 3,541,067 $ 952,385 $ 814,392 $ 152,800 $ 2,292 $ 5,462,936 Three Months Ended September 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 Provision charged to operating expense (1,149 ) 430 2,004 (187 ) — 1,098 Less loans charged-off (2,219 ) (1,537 ) (791 ) — — (4,547 ) Add back recoveries of loans previously charged-off 389 653 111 — — 1,153 Ending balance $ 50,956 $ 5,374 $ 17,121 $ 805 $ — $ 74,256 Nine Months Ended September 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 53,884 $ 5,035 $ 14,307 $ 974 $ — $ 74,200 Provision charged to operating expense (1,718 ) 2,201 3,220 (170 ) — 3,533 Less loans charged-off (3,014 ) (3,675 ) (1,227 ) — — (7,916 ) Add back recoveries of loans previously charged-off 1,804 1,813 821 1 — 4,439 Ending balance $ 50,956 $ 5,374 $ 17,121 $ 805 $ — $ 74,256 As of December 31, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 4,794 $ — $ 6,487 $ 294 $ — $ 11,575 Loans collectively evaluated for impairment 47,502 5,144 12,288 308 — 65,242 Allowance for loan losses $ 52,296 $ 5,144 $ 18,775 $ 602 $ — $ 76,817 Total loans: Individually evaluated for impairment $ 66,516 $ — $ 24,471 $ 978 $ — $ 91,965 Collectively evaluated for impairment 3,346,546 844,353 767,945 141,173 1,339 5,101,356 Total loans $ 3,413,062 $ 844,353 $ 792,416 $ 142,151 $ 1,339 $ 5,193,321

OREO (Tables)

OREO (Tables)	9 Months Ended
	Sep. 30, 2016
Repossessed Assets [Abstract]
Other Real Estate Owned Roll Forward	Information with respect to the Company's other real estate owned follows: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Beginning balance $ 7,908 $ 11,773 $ 6,254 $ 13,554 OREO acquired through acquisition 1,120 — 1,120 — Additions 1,316 984 5,335 5,380 Valuation adjustments — (73 ) (603 ) (179 ) Dispositions (897 ) (4,653 ) (2,659 ) (10,724 ) Ending balance $ 9,447 $ 8,031 $ 9,447 $ 8,031 Foreclosed residential real estate properties of $ 2,730 and $1,686 were included in other real estate owned as of September 30, 2016 and December 31, 2015, respectively. The Company did not have any consumer mortgage loans collateralized by residential real estate property that were in the process of foreclosure as of September 30, 2016 or December 31, 2015.

Derivatives and Hedging (Tables

Derivatives and Hedging (Tables)	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]	September 30, 2016 December 31, 2015 Notional Amount Estimated Fair Value Notional Amount Estimated Fair Value Derivative Assets (included in other assets on balance sheet): Derivatives designated as hedges: Interest rate swap contracts $ — $ — $ 100,000 $ 165 Non-hedging interest rate derivatives: Interest rate swap contracts 20,757 1,577 9,369 788 Interest rate lock commitments 92,847 2,590 — — Total derivative assets $ 113,604 $ 4,167 $ 109,369 $ 953 Derivative Liabilities (included in accounts payable and accrued expenses on balance sheet): Derivatives designated as hedges: Interest rate swap contracts $ 100,000 $ 2,325 $ — $ — Non-hedging interest rate derivatives: Interest rate swap contracts 20,757 1,701 9,369 829 Forward loan sales contracts 156,264 620 — — Total derivative liabilities $ 277,021 $ 4,646 $ 9,369 $ 829
Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Derivatives designated as hedges: Amount of gain (loss) recognized in other comprehensive income (effective portion) $ 512 $ (436 ) $ (2,490 ) $ (436 ) Non-hedging interest rate derivatives: Amount of loss recognized in other non-interest income (3 ) (31 ) (82 ) (48 ) Amount of net fee income recognized in other non-interest income — — 245 — Amount of net gains recognized in mortgage banking revenues 752 — 1,970 —

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings per Share	The following table sets forth the computation of basic and diluted earnings per share for the three and nine month periods ended September 30, 2016 and 2015 : Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Net income $ 25,193 $ 20,162 $ 70,871 $ 63,364 Weighted average common shares outstanding for basic earnings per share computation 44,415,213 45,150,104 44,505,544 45,223,988 Dilutive effects of stock-based compensation 390,708 428,874 379,368 481,636 Weighted average common shares outstanding for diluted earnings per common share computation 44,805,921 45,578,978 44,884,912 45,705,624 Basic earnings per common share $ 0.57 $ 0.45 $ 1.59 $ 1.40 Diluted earnings per common share $ 0.56 $ 0.44 $ 1.58 $ 1.39 Anti-dilutive unvested time restricted stock 135 5,884 95,886 5,884

Regulatory Capital (Tables)

Regulatory Capital (Tables)	9 Months Ended
	Sep. 30, 2016
Banking and Thrift [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations	Actual capital amounts and ratios for the Company and its bank subsidiary, as of September 30, 2016 and December 31, 2015 are presented in the following tables: Actual Adequately Capitalized Basel III Phase-In Schedule Adequately Capitalized Basel III Fully Phased-In Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio Amount Ratio September 30, 2016 Total risk-based capital: Consolidated $ 962,182 14.9 % $ 558,157 8.6 % $ 679,495 10.5 % $ 647,138 10.0 % FIB 898,288 13.9 556,154 8.6 677,057 10.5 644,816 10.0 Tier 1 risk-based capital: Consolidated 877,285 13.6 428,729 6.6 550,068 8.5 517,711 8.0 FIB 817,678 12.7 427,191 6.6 548,094 8.5 515,853 8.0 Common equity tier 1 risk-based capital: Consolidated 797,285 12.3 331,658 5.1 452,997 7.0 420,640 6.5 FIB 817,678 12.7 330,468 5.1 451,371 7.0 419,131 6.5 Leverage capital ratio: Consolidated 877,285 10.2 343,228 4.0 343,228 4.0 429,035 5.0 FIB 817,678 9.5 342,629 4.0 342,629 4.0 428,286 5.0 Actual Adequately Capitalized Basel III Phase-In Schedule Adequately Capitalized Basel III Fully Phased-In Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio Amount Ratio December 31, 2015 Total risk-based capital: Consolidated $ 946,156 15.4 % $ 492,692 8.0 % $ 646,658 10.5 % $ 615,865 10.0 % FIB 882,504 14.4 490,866 8.0 644,262 10.5 613,582 10.0 Tier 1 risk-based capital: Consolidated 861,339 14.0 369,519 6.0 523,485 8.5 $ 492,692 8.0 FIB 805,805 13.1 368,149 6.0 521,545 8.5 490,866 8.0 Common equity tier 1 risk-based capital: Consolidated 781,339 12.7 277,139 4.5 431,105 7.0 $ 400,312 6.5 FIB 805,805 13.1 276,112 4.5 429,508 7.0 398,829 6.5 Leverage capital ratio: Consolidated 861,339 10.1 340,480 4.0 340,480 4.0 $ 425,600 5.0 FIB 805,805 9.5 339,316 4.0 339,316 4.0 424,145 5.0 (1) The ratios for the well capitalized requirement are only applicable to FIB. However, the Company manages its capital position as if the requirement applies to the consolidated entity and has presented the ratios as if they also applied on a consolidated basis.

Other Comprehensive Income (Tab

Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Schedule of Comprehensive Income (Loss)	Other Comprehensive Income/Loss The gross amounts of each component of other comprehensive income and the related tax effects are as follows: Pre-tax Tax Expense (Benefit) Net of Tax Three Months Ended September 30, 2016 2015 2016 2015 2016 2015 Investment securities available-for sale: Change in net unrealized gains during period $ (3,430 ) $ 10,855 $ (1,359 ) $ 4,272 $ (2,071 ) $ 6,583 Reclassification adjustment for net gains included in net income (225 ) (23 ) (89 ) (10 ) (136 ) (13 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 490 448 209 177 281 271 Unrealized loss on derivatives 512 (436 ) 195 (172 ) 317 (264 ) Defined benefits post-retirement benefit plan: Change in net actuarial loss 15 15 6 6 9 9 Total other comprehensive income (loss) $ (2,638 ) $ 10,859 $ (1,038 ) $ 4,273 $ (1,600 ) $ 6,586 Pre-tax Tax Expense (Benefit) Net of Tax Nine Months Ended September 30, 2016 2015 2016 2015 2016 2015 Investment securities available-for sale: Change in net unrealized gains during period $ 15,241 $ 12,264 $ 5,963 $ 4,827 $ 9,278 $ 7,437 Reclassification adjustment for net gains included in net income (312 ) (75 ) (123 ) (30 ) (189 ) (45 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 1,394 1,353 549 532 845 821 Unrealized loss on derivatives (2,490 ) (436 ) (946 ) (172 ) (1,544 ) (264 ) Defined benefits post-retirement benefit plan: Change in net actuarial loss 43 43 17 17 26 26 Total other comprehensive income $ 13,876 $ 13,149 $ 5,460 $ 5,174 $ 8,416 $ 7,975
Schedule of Accumulated Other Comprehensive Income (Loss)	The components of accumulated other comprehensive income, net of related tax effects, are as follows: September 30, December 31, Net unrealized gain on investment securities available-for-sale $ 10,618 $ 684 Net unrealized gain (loss) on derivatives (1,444 ) 100 Net actuarial loss on defined benefit post-retirement benefit plans (352 ) (378 ) Net accumulated other comprehensive income $ 8,822 $ 406

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis	Financial assets and financial liabilities measured at fair value on a recurring basis are as follows: Fair Value Measurements at Reporting Date Using As of September 30, 2016 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Investment securities available-for-sale: U.S. Treasury Notes $ 3,639 $ — $ 3,639 $ — Obligations of U.S. government agencies 441,127 — 441,127 — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 1,083,369 — 1,083,369 — Private mortgage-backed securities 124 — 124 — Other investments 4,962 — 4,962 — Loans held for sale 67,979 — 67,979 — Derivative assets: Interest rate swap contracts 1,577 — 1,577 — Interest rate lock commitments 2,590 — 2,590 — Derivative liabilities: Interest rate swap contracts 4,026 — 4,026 — Forward loan sale contracts 620 — 620 — Deferred compensation plan assets 10,534 — 10,534 — Deferred compensation plan liabilities 10,534 — 10,534 — Fair Value Measurements at Reporting Date Using As of December 31, 2015 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Investment securities available-for-sale: U.S. Treasury notes $ 3,911 $ — $ 3,911 $ — Obligations of U.S. government agencies 520,181 — 520,181 — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 929,046 — 929,046 — Private mortgage-backed securities 156 — 156 — Other investments 3,546 — 3,546 — Derivative assets: Interest rate swap contracts 953 — 953 — Derivative liabilities Interest rate swap contracts 829 — 829 — Deferred compensation plan assets 10,149 — 10,149 — Deferred compensation plan liabilities 10,149 — 10,149 —
Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Non-Recurring Basis	The following table presents information about the Company’s assets and liabilities measured at fair value on a non-recurring basis: Fair Value Measurements at Reporting Date Using As of September 30, 2016 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Impaired loans $ 39,746 $ — $ — $ 39,746 Other real estate owned 2,808 — — 2,808 Long-lived assets to be disposed of by sale 1,506 — — 1,506 Fair Value Measurements at Reporting Date Using As of December 31, 2015 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Impaired loans $ 20,875 $ — $ — $ 20,875 Other real estate owned 1,789 — — 1,789 Long-lived assets to be disposed of by sale 1,506 — — 1,506
Fair Value Inputs, Assets, Quantitative Information	Fair Value As of September 30, 2016 December 31, 2015 Valuation Technique Unobservable Inputs Range (Weighted Average) Impaired loans $ 39,746 $ 20,875 Appraisal Appraisal adjustment 0% - 53% (38%) Other real estate owned 2,808 1,789 Appraisal Appraisal adjustment 2% - 96% (19%) Long-lived assets to be disposed of by sale 1,506 1,506 Appraisal Appraisal adjustment 0% - 9% (6%)
Fair Value, by Balance Sheet Grouping	Fair Value Measurements at Reporting Date Using As of September 30, 2016 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets: Cash and cash equivalents $ 701,367 $ 701,367 $ 701,367 $ — $ — Investment securities available-for-sale 1,533,221 1,533,221 — 1,533,221 — Investment securities held-to-maturity 539,052 554,048 — 554,048 — Accrued interest receivable 31,002 31,002 — 31,002 — Mortgage servicing rights, net 17,322 25,845 — 25,845 — Loans held for sale 67,979 67,979 — 67,979 — Net loans held for investment 5,462,936 5,321,409 — 5,281,663 39,746 Derivative assets 4,167 4,167 — 4,167 — Deferred compensation plan assets 10,534 10,534 — 10,534 — Total financial assets $ 8,367,580 $ 8,249,572 $ 701,367 $ 7,508,459 $ 39,746 Financial liabilities: Total deposits, excluding time deposits $ 6,235,993 $ 6,235,993 $ 6,235,993 $ — $ — Time deposits 1,092,588 1,090,434 — 1,090,434 — Securities sold under repurchase agreements 476,768 476,768 — 476,768 — Other borrowed funds 8 8 — 8 — Accrued interest payable 5,622 5,622 — 5,622 — Long-term debt 27,949 27,801 — 27,801 — Subordinated debentures held by subsidiary trusts 82,477 72,803 — 72,803 — Derivative liabilities 4,646 4,646 — 4,646 — Deferred compensation plan liabilities 10,534 10,534 — 10,534 — Total financial liabilities $ 7,936,585 $ 7,924,609 $ 6,235,993 $ 1,688,616 $ — Fair Value Measurements at Reporting Date Using As of December 31, 2015 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets: Cash and cash equivalents $ 780,457 $ 780,457 $ 780,457 $ — $ — Investment securities available-for-sale 1,456,840 1,456,840 — 1,456,840 — Investment securities held-to-maturity 600,665 607,550 — 607,550 — Accrued interest receivable 27,729 27,729 — 27,729 — Mortgage servicing rights, net 15,621 31,011 — 31,011 — Net loans 5,169,379 5,128,705 — 5,107,830 20,875 Derivative assets 953 953 — 953 — Deferred compensation plan assets 10,149 10,149 — 10,149 — Total financial assets $ 8,061,793 $ 8,043,394 $ 780,457 $ 7,242,062 $ 20,875 Financial liabilities: Total deposits, excluding time deposits $ 5,957,345 $ 5,975,345 $ 5,975,345 $ — $ — Time deposits 1,131,592 1,137,289 — 1,137,289 — Securities sold under repurchase agreements 510,635 510,635 — 510,635 — Other borrowed funds 2 2 — 2 — Accrued interest payable 4,960 4,960 — 4,960 — Long-term debt 27,885 27,622 — 27,622 — Subordinated debentures held by subsidiary trusts 82,477 74,969 — 74,969 — Derivative liabilities 829 829 — 829 — Deferred compensation plan liabilities 10,149 10,149 — 10,149 — Total financial liabilities $ 7,725,874 $ 7,741,800 $ 5,975,345 $ 1,766,455 $ —

Business Combination (Details)

Business Combination (Details) $ in Thousands	Aug. 12, 2016USD ($)	Apr. 06, 2016	Jul. 24, 2015	Sep. 30, 2016USD ($)
Flathead Bank Acquisition, as Recorded by the Company
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 34,100
Flathead Bank
Business Acquisition [Line Items]
Business Acquisition, Date of Acquisition Agreement		Apr. 6, 2016
Business Acquisition, Effective Date of Acquisition	Aug. 12, 2016
Business Acquisition, Transaction Costs				$ 1,197
Flathead Bank | Core Deposits [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Net				$ 2,486
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life				9 years
United Bank
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Jul. 24, 2015
Number of Subsidiary Banks				1
Goodwill, Purchase Accounting Adjustments				$ 42

Acquisitions Schedule of Recogn

Acquisitions Schedule of Recognized Identifiable Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands		Aug. 12, 2016	Sep. 30, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill			$ 212,820	$ 204,523
Flathead Bank Acquisition, as recorded by Flathead Bank
Business Acquisition [Line Items]
Cash and Cash Equivalents		$ 52,653
Investment Securities		99,801
Loans and Leases Receivable		87,181
Allowance for Loan Losses		(1,567)
Premises and Equipment		4,529
Core Deposit Intangible Assets		0
Company Owned Life Insurance		6,386
Other Assets		5,200
Total Assets Acquired		254,183
Deposits		209,673
Repurchase Agreements		18,050
Other Liabilities		838
Total Liabilities Assumed		228,561
Net Assets Acquired		25,622
Flathead Bank Acquisition, Fair Value Adjustments
Business Acquisition [Line Items]
Cash and Cash Equivalents		0
Investment Securities	[1]	1,315
Loans and Leases Receivable	[2]	(3,833)
Allowance for Loan Losses	[3]	(1,567)
Premises and Equipment	[4]	891
Core Deposit Intangible Assets	[5]	2,486
Company Owned Life Insurance		0
Other Assets	[6]	(2,373)
Total Assets Acquired		53
Deposits	[7]	(86)
Repurchase Agreements		0
Other Liabilities		0
Total Liabilities Assumed		(86)
Net Assets Acquired		139
Flathead Bank Acquisition, as Recorded by the Company
Business Acquisition [Line Items]
Cash and Cash Equivalents		52,653
Investment Securities		101,116
Loans and Leases Receivable		83,348
Allowance for Loan Losses		0
Premises and Equipment		5,420
Core Deposit Intangible Assets		2,486
Company Owned Life Insurance		6,386
Other Assets		2,827
Total Assets Acquired		254,236
Deposits		209,587
Repurchase Agreements		18,050
Other Liabilities		838
Total Liabilities Assumed		228,475
Net Assets Acquired		25,761
Payments to Acquire Businesses, Gross		34,100
Goodwill		$ 8,339
[1]	Write up the book value of investments to their estimated fair values based upon two external pricing services.
[2]	Write down of the book value of loans to their estimated fair values. The fair value of loans was estimated using cash flow projections based on the remaining maturity and repricing terms, adjusted for estimated future credit losses and prepayments and discounted to present value using a risk-adjusted market rate for similar loans. The fair value of collateral dependent loans acquired with deteriorated credit quality was estimated based on the Company's analysis of the fair value of each loan's underlying collateral, discounted using market-derived rates of return with consideration given to the period of time and costs associated with foreclosure and disposition of the collateral.
[3]	Adjustment to remove the Flathead allowance for loan losses at acquisition date as the credit risk is accounted for in the fair value adjustment for loans receivable described in (2) above.
[4]	Write up of the book value of premises and equipment to their estimated fair values on the date of acquisition based upon appraisals obtained from an independent third party appraiser or signed purchase agreements.
[5]	Adjustment represents the value of the core deposit base assumed in the acquisition based upon an internal valuation using industry averages obtained from an investment banking firm.
[6]	Adjustment consists of the write-off of pre-existing goodwill and pre-paid assets.
[7]	Decrease in book value of time deposits to their estimated fair values based upon interest rates of similar time deposits with similar terms on the date of acquisition.

Deteriorated Loans Transferred

Deteriorated Loans Transferred In (Details) $ in Thousands	Aug. 12, 2016USD ($)
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities [Abstract]
Contractually Required Payments Receivable at Acquisition	$ 19,324
Nonaccretable Difference	10,999
Cash Flows Expected to be Collected at Acquisition	8,325
Accretable Yield	1,113
Acquired Loans at Fair Value	$ 7,212

Acquisitions Schedule of Acquir

Acquisitions Schedule of Acquired Loans not Deemed to Have Credit Impairment (Details) $ in Thousands	Aug. 12, 2016USD ($)
Business Combinations [Abstract]
Loans Acquired in Transfer, Contractually Required Payments Receivable at Acquisition	$ 100,616
Loans Acquired in Transfer, Nonaccretable Difference	4,702
Loans Acquired in Transfer at Acquisition Fair Value	$ 76,136

Acquisitions Pro Forma (Details

Acquisitions Pro Forma (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Business Combinations [Abstract]
Pro Forma Acquisition Expenses, Net of Tax			$ 778
Business Acquisition, Pro Forma Interest Income	$ 75,736	$ 72,605	223,547	$ 207,425
Business Acquisition, Pro Forma Non Interest Income	32,114	31,647	95,011	91,218
Business Acquisition, Pro Forma Revenue	107,850	104,252	318,558	298,643
Business Acquisition, Pro Forma Net Income (Loss)	$ 26,207	$ 20,783	$ 72,844	$ 64,545

Amortized Cost and Approximate

Amortized Cost and Approximate Fair Values of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Available-for-Sale:
Available-for-Sale, Amortized Cost	$ 1,511,783	$ 1,450,396
Available-for-sale Securities, Gross Unrealized Gain1	21,980	10,169
Available-for-sale Securities, Gross Unrealized Loss1	(542)	(3,725)
Available-for-Sale, Estimated Fair Value	1,533,221	1,456,840
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	539,052	600,665
Held-to-maturity Securities, Gross Unrealized Gain1	21,621	12,854
Held-to-maturity Securities, Gross Unrealized Loss1	(6,625)	(5,969)
Held-to-Maturity, Estimated Fair Value	554,048	607,550
US Treasury Securities [Member]
Available-for-Sale:
Available-for-Sale, Amortized Cost	3,609	3,912
Available-for-sale Securities, Gross Unrealized Gain1	30	3
Available-for-sale Securities, Gross Unrealized Loss1	0	(4)
Available-for-Sale, Estimated Fair Value	3,639	3,911
Obligations of U.S. government agencies
Available-for-Sale:
Available-for-Sale, Amortized Cost	439,488	521,079
Available-for-sale Securities, Gross Unrealized Gain1	1,819	712
Available-for-sale Securities, Gross Unrealized Loss1	(180)	(1,610)
Available-for-Sale, Estimated Fair Value	441,127	520,181
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	19,737	19,738
Held-to-maturity Securities, Gross Unrealized Gain1	315	0
Held-to-maturity Securities, Gross Unrealized Loss1	0	(102)
Held-to-Maturity, Estimated Fair Value	20,052	19,636
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations
Available-for-Sale:
Available-for-Sale, Amortized Cost	1,063,642	921,699
Available-for-sale Securities, Gross Unrealized Gain1	20,088	9,448
Available-for-sale Securities, Gross Unrealized Loss1	(361)	(2,101)
Available-for-Sale, Estimated Fair Value	1,083,369	929,046
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	300,018	356,742
Held-to-maturity Securities, Gross Unrealized Gain1	14,643	7,686
Held-to-maturity Securities, Gross Unrealized Loss1	(6,581)	(5,420)
Held-to-Maturity, Estimated Fair Value	308,080	359,008
Private mortgage-backed securities
Available-for-Sale:
Available-for-Sale, Amortized Cost	124	156
Available-for-sale Securities, Gross Unrealized Gain1	1	1
Available-for-sale Securities, Gross Unrealized Loss1	(1)	(1)
Available-for-Sale, Estimated Fair Value	124	156
State, county and municipal securities
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	165,891	173,785
Held-to-maturity Securities, Gross Unrealized Gain1	6,048	5,103
Held-to-maturity Securities, Gross Unrealized Loss1	(30)	(227)
Held-to-Maturity, Estimated Fair Value	171,909	178,661
Corporate securities
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	53,146	50,046
Held-to-maturity Securities, Gross Unrealized Gain1	614	64
Held-to-maturity Securities, Gross Unrealized Loss1	(14)	(220)
Held-to-Maturity, Estimated Fair Value	53,746	49,890
Other Investments
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	260	354
Held-to-maturity Securities, Gross Unrealized Gain1	1	1
Held-to-maturity Securities, Gross Unrealized Loss1	0	0
Held-to-Maturity, Estimated Fair Value	261	355
Other Investments
Available-for-Sale:
Available-for-Sale, Amortized Cost	4,920	3,550
Available-for-sale Securities, Gross Unrealized Gain1	42	5
Available-for-sale Securities, Gross Unrealized Loss1	0	(9)
Available-for-Sale, Estimated Fair Value	$ 4,962	$ 3,546

Investment Securities Realized

Investment Securities Realized Gains (Losses) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$ 239	$ 23	$ 404	$ 75
Gross realized losses	$ (14)	$ 0	$ (92)	$ 0

Investment Securities Transfer

Investment Securities Transfer from AFS to HTM (Details) $ in Thousands	Oct. 30, 2015USD ($)
Transfer from AFS to HTM [Abstract]
Available-for-Sale Securities Transferred to Held-to-Maturity, Amortized Costs	$ 100,343
Available-for-Sale Securities Transferred to Held-to-Maturity, Fair Values	100,140
Available-for-Sale Securities Transferred to Held-to-Maturity, Unrealized Net Gain (Loss)	$ 203
Remaining Expected Lives of Available-for-Sale Securities Transferred to Held-to-Maturity	4 years

Investment Securities Gross Unr

Investment Securities Gross Unrealized Losses and Fair Values of Investment Securities (Details) $ in Thousands	Sep. 30, 2016USD ($)securities	Dec. 31, 2015USD ($)securities
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 83,050	$ 556,823
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(222)	(2,667)
Available-for-Sale, 12 Months or More Fair Value	121,245	82,690
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(320)	(1,058)
Available-for-Sale, Total Fair Value	204,295	639,513
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(542)	(3,725)
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	21,593	128,350
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(2,759)	(4,649)
Held-to-Maturity, 12 Months or More Fair Value	21,366	79,015
Held-to-Maturity, 12 Months or More Gross Unrealized Losses	(3,866)	(1,320)
Held-to-Maturity, Total Fair Value	42,959	207,365
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	$ (6,625)	$ (5,969)
Available-for-Sale and Held-to-Maturity:
Investment Securities in an Unrealized Loss Position (Number of Securities) | securities	126	198
US Treasury Securities [Member]
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		$ 2,092
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1		(4)
Available-for-Sale, 12 Months or More Fair Value		0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1		0
Available-for-Sale, Total Fair Value		2,092
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1		(4)
Obligations of U.S. government agencies
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 0	209,631
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	0	(1,077)
Available-for-Sale, 12 Months or More Fair Value	103,776	54,619
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(180)	(533)
Available-for-Sale, Total Fair Value	103,776	264,250
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(180)	(1,610)
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value		19,738
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1		(102)
Held-to-Maturity, 12 Months or More Fair Value		0
Held-to-Maturity, 12 Months or More Gross Unrealized Losses		0
Held-to-Maturity, Total Fair Value		19,738
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1		(102)
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	83,050	343,875
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(222)	(1,577)
Available-for-Sale, 12 Months or More Fair Value	17,419	28,010
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(139)	(524)
Available-for-Sale, Total Fair Value	100,469	371,885
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(361)	(2,101)
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	8,791	67,295
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(2,721)	(4,288)
Held-to-Maturity, 12 Months or More Fair Value	18,523	69,539
Held-to-Maturity, 12 Months or More Gross Unrealized Losses	(3,860)	(1,132)
Held-to-Maturity, Total Fair Value	27,314	136,834
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(6,581)	(5,420)
State, county and municipal securities
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	7,746	10,182
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(24)	(39)
Held-to-Maturity, 12 Months or More Fair Value	2,843	9,476
Held-to-Maturity, 12 Months or More Gross Unrealized Losses	(6)	(188)
Held-to-Maturity, Total Fair Value	10,589	19,658
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(30)	(227)
Private mortgage-backed securities
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	0	0
Available-for-Sale, 12 Months or More Fair Value	50	61
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(1)	(1)
Available-for-Sale, Total Fair Value	50	61
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(1)	(1)
Corporate securities
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	5,056	31,135
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(14)	(220)
Held-to-Maturity, 12 Months or More Fair Value	0	0
Held-to-Maturity, 12 Months or More Gross Unrealized Losses	0	0
Held-to-Maturity, Total Fair Value	5,056	31,135
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	$ (14)	(220)
Other Investments
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		1,225
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1		(9)
Available-for-Sale, 12 Months or More Fair Value		0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1		0
Available-for-Sale, Total Fair Value		1,225
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1		$ (9)

Maturities of Investment Securi

Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Rolling Maturity
Available-for-Sale Amortized Cost, Within One Year	$ 340,072
Available-for-Sale Amortized Cost, After One Year but Within Five Years	1,030,847
Available-for-Sale Amortized Cost, After Five Years but Within Ten Years	108,831
Available-for-Sale Amortized Cost, After Ten Years	32,033
Available-for-Sale, Amortized Cost	1,511,783	$ 1,450,396
Available-for-sale Securities, Debt Maturities, Fair Value, Rolling Maturity
Available-for-Sale Estimated Fair Value, Within One Year	345,636
Available-for-Sale Estimated Fair Value, After One Year but Within Five Years	1,045,108
Available-for-Sale Estimated Fair Value, After Ten Years	109,852
Available-for-Sale Estimated Fair Value, After Five Years but Within Ten Years	32,625
Available-for-Sale, Estimated Fair Value	1,533,221	1,456,840
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount
Held-to-Maturity Amortized Cost, Within One Year	99,864
Held-to-Maturity Amortized Cost, After One Year but Within Five Years	290,601
Held-to-Maturity Amortized Cost, After Five Years but Within Ten Years	117,829
Held-to-Maturity Amortized Cost, After Ten Years	30,758
Held-to-Maturity, Amortized Cost	539,052	600,665
Held-to-maturity Securities, Debt Maturities, Fair Value, Rolling Maturity
Held-to-Maturity Estimated Fair Value, Within One Year	97,362
Held-to-Maturity Estimated Fair Value, After One Year but Within Five Years	304,804
Held-to-Maturity Estimated Fair Value, After Five Years but Within Ten Years	121,191
Held-to-Maturity Estimated Fair Value, After Ten Years	30,691
Held-to-Maturity, Estimated Fair Value	554,048	$ 607,550
Callable Within One Year
Available-for-sale Securities and Held-to-maturity Securities
Investment Securities Primarily Classified as Available-for-Sale, Amortized Costs, After One Year but Within Five Years	220,907
Investment Securities Primarily Classified as Available-for-Sale, Fair Value, After One Year but Within Five Years	$ 221,189

Schedule of Loans by Class (Det

Schedule of Loans by Class (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Loans and Leases Receivable [Line Items]
Loans held for investment	$ 5,462,936	$ 5,193,321
Mortgage loans held for sale	67,979	52,875
Total loans	5,530,915	5,246,196
Commercial real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	1,843,120	1,793,258
Land acquisition & development construction real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	212,680	224,066
Residential construction real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	137,014	111,763
Commercial construction real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	128,154	94,890
Total construction loans
Loans and Leases Receivable [Line Items]
Loans held for investment	477,848	430,719
Residential real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	1,047,150	1,032,851
Agricultural real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	172,949	156,234
Total real estate loans
Loans and Leases Receivable [Line Items]
Loans held for investment	3,541,067	3,413,062
Indirect consumer
Loans and Leases Receivable [Line Items]
Loans held for investment	731,901	622,529
Other consumer
Loans and Leases Receivable [Line Items]
Loans held for investment	153,624	153,717
Credit card consumer
Loans and Leases Receivable [Line Items]
Loans held for investment	66,860	68,107
Total consumer loans
Loans and Leases Receivable [Line Items]
Loans held for investment	952,385	844,353
Commercial
Loans and Leases Receivable [Line Items]
Loans held for investment	814,392	792,416
Agricultural
Loans and Leases Receivable [Line Items]
Loans held for investment	152,800	142,151
Other, including overdrafts
Loans and Leases Receivable [Line Items]
Loans held for investment	$ 2,292	$ 1,339

Schedule of Recorded Investment

Schedule of Recorded Investment in Past Due Loans by Class (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Mortgage loans held for sale	$ 67,979		$ 67,979		$ 52,875
Loans held for investment	5,462,936		5,462,936		5,193,321
Total loans	5,530,915		5,530,915		5,246,196
Interest Income on Non-Accrual Loans if Accrued	820	$ 828	2,492	$ 2,331
Commercial real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	9,234		9,234		7,193
Current Loans	1,806,929		1,806,929		1,762,294
Non-accrual Loans	26,957		26,957		23,771
Loans held for investment	1,843,120		1,843,120		1,793,258
Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	974		974		4,678
Current Loans	206,388		206,388		212,757
Non-accrual Loans	5,318		5,318		6,631
Loans held for investment	212,680		212,680		224,066
Residential construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	829		829		1,288
Current Loans	135,919		135,919		110,182
Non-accrual Loans	266		266		293
Loans held for investment	137,014		137,014		111,763
Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	3,432		3,432		3,232
Current Loans	123,905		123,905		90,703
Non-accrual Loans	817		817		955
Loans held for investment	128,154		128,154		94,890
Total construction loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	5,235		5,235		9,198
Current Loans	466,212		466,212		413,642
Non-accrual Loans	6,401		6,401		7,879
Loans held for investment	477,848		477,848		430,719
Residential real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	8,726		8,726		9,250
Current Loans	1,035,626		1,035,626		1,018,359
Non-accrual Loans	2,798		2,798		5,242
Loans held for investment	1,047,150		1,047,150		1,032,851
Agricultural real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	840		840		193
Current Loans	168,773		168,773		150,686
Non-accrual Loans	3,336		3,336		5,355
Loans held for investment	172,949		172,949		156,234
Total real estate loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	24,035		24,035		25,834
Current Loans	3,477,540		3,477,540		3,344,981
Non-accrual Loans	39,492		39,492		42,247
Loans held for investment	3,541,067		3,541,067		3,413,062
Indirect consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	8,064		8,064		7,974
Current Loans	723,048		723,048		614,029
Non-accrual Loans	789		789		526
Loans held for investment	731,901		731,901		622,529
Other consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,378		1,378		1,677
Current Loans	151,886		151,886		151,381
Non-accrual Loans	360		360		659
Loans held for investment	153,624		153,624		153,717
Credit card consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,537		1,537		1,327
Current Loans	65,323		65,323		66,768
Non-accrual Loans	0		0		12
Loans held for investment	66,860		66,860		68,107
Total consumer loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	10,979		10,979		10,978
Current Loans	940,257		940,257		832,178
Non-accrual Loans	1,149		1,149		1,197
Loans held for investment	952,385		952,385		844,353
Commercial
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	4,921		4,921		10,252
Current Loans	782,378		782,378		759,851
Non-accrual Loans	27,093		27,093		22,313
Loans held for investment	814,392		814,392		792,416
Agricultural
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	324		324		1,093
Current Loans	148,741		148,741		140,430
Non-accrual Loans	3,735		3,735		628
Loans held for investment	152,800		152,800		142,151
Other, including overdrafts
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	311		311		314
Current Loans	1,981		1,981		1,025
Non-accrual Loans	0		0		0
Loans held for investment	2,292		2,292		1,339
Loans held for investment
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	40,570		40,570		48,471
Current Loans	5,350,897		5,350,897		5,078,465
Non-accrual Loans	71,469		71,469		66,385
Loans held for investment	5,462,936		5,462,936		5,193,321
Mortgage loans originated for sale
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Current Loans	67,979		67,979		52,875
Non-accrual Loans	0		0		0
Total loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	40,570		40,570		48,471
Current Loans	5,418,876		5,418,876		5,131,340
Non-accrual Loans	71,469		71,469		66,385
Total loans	5,530,915		5,530,915		5,246,196
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	8,023		8,023		6,051
Financing Receivables, 30 to 59 Days Past Due [Member] | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	500		500		3,190
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	592		592		1,288
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	3,375		3,375		3,232
Financing Receivables, 30 to 59 Days Past Due [Member] | Total construction loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	4,467		4,467		7,710
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	4,019		4,019		5,991
Financing Receivables, 30 to 59 Days Past Due [Member] | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	10		10		176
Financing Receivables, 30 to 59 Days Past Due [Member] | Total real estate loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	16,519		16,519		19,928
Financing Receivables, 30 to 59 Days Past Due [Member] | Indirect consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	5,707		5,707		6,675
Financing Receivables, 30 to 59 Days Past Due [Member] | Other consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,029		1,029		1,312
Financing Receivables, 30 to 59 Days Past Due [Member] | Credit card consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	711		711		533
Financing Receivables, 30 to 59 Days Past Due [Member] | Total consumer loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	7,447		7,447		8,520
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	2,366		2,366		8,493
Financing Receivables, 30 to 59 Days Past Due [Member] | Agricultural
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	219		219		879
Financing Receivables, 30 to 59 Days Past Due [Member] | Other, including overdrafts
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Financing Receivables, 30 to 59 Days Past Due [Member] | Loans held for investment
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	26,551		26,551		37,820
Financing Receivables, 30 to 59 Days Past Due [Member] | Mortgage loans originated for sale
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Financing Receivables, 30 to 59 Days Past Due [Member] | Total loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	26,551		26,551		37,820
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	484		484		724
Financing Receivables, 60 to 89 Days Past Due [Member] | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	424		424		163
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	57		57		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total construction loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	481		481		163
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,870		1,870		1,196
Financing Receivables, 60 to 89 Days Past Due [Member] | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		17
Financing Receivables, 60 to 89 Days Past Due [Member] | Total real estate loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	2,835		2,835		2,100
Financing Receivables, 60 to 89 Days Past Due [Member] | Indirect consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,735		1,735		1,089
Financing Receivables, 60 to 89 Days Past Due [Member] | Other consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	329		329		331
Financing Receivables, 60 to 89 Days Past Due [Member] | Credit card consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	261		261		317
Financing Receivables, 60 to 89 Days Past Due [Member] | Total consumer loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	2,325		2,325		1,737
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	640		640		1,060
Financing Receivables, 60 to 89 Days Past Due [Member] | Agricultural
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	88		88		152
Financing Receivables, 60 to 89 Days Past Due [Member] | Other, including overdrafts
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Loans held for investment
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	5,888		5,888		5,049
Financing Receivables, 60 to 89 Days Past Due [Member] | Mortgage loans originated for sale
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	5,888		5,888		5,049
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	727		727		418
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	50		50		1,325
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	237		237		0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Total construction loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	287		287		1,325
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Residential real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	2,837		2,837		2,063
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	830		830		0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Total real estate loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	4,681		4,681		3,806
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Indirect consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	622		622		210
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Other consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	20		20		34
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Credit card consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	565		565		477
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Total consumer loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,207		1,207		721
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,915		1,915		699
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Agricultural
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	17		17		62
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Other, including overdrafts
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	311		311		314
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Loans held for investment
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	8,131		8,131		5,602
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Mortgage loans originated for sale
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Total loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	$ 8,131		$ 8,131		$ 5,602

Loans Schedule of Loans Acquire

Loans Schedule of Loans Acquired from Business Combinations (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities [Abstract]
Outstanding Balance	$ 38,505	$ 35,265
Carrying Amount Net, Accrual Status	23,665	22,867
Total Carrying Value	$ 23,665	$ 22,867

Loans Certain Loans Acquired in

Loans Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning Balance	$ 5,905	$ 7,482	$ 6,713	$ 5,781
Additions	1,114	624	1,114	1,073
Accretion Income	(670)	(845)	(1,899)	(2,200)
Reductions Due to Exit Events	(595)	(143)	(900)	(539)
Reclassifications from (to) nonaccretable differences	729	347	1,455	3,350
Ending Balance	$ 6,483	$ 7,465	$ 6,483	$ 7,465

Loans Schedule of Recorded Inve

Loans Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	$ 125,681		$ 125,681		$ 120,387
Recorded Investment With No Allowance	46,800		46,800		56,236
Recorded Investment With Allowance	52,342		52,342		35,729
Total Recorded Investment	99,142		99,142		91,965
Related Allowance	18,565		18,565		11,575
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	81,974	$ 82,674	82,798	$ 80,836
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	192	305	414	860
Interest Income on Impaired Loans If Interest Had Been Accrued	993	998	2,994	2,932
Commercial real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	58,137		58,137		58,179
Recorded Investment With No Allowance	16,518		16,518		27,882
Recorded Investment With Allowance	29,451		29,451		17,614
Total Recorded Investment	45,969		45,969		45,496
Related Allowance	5,868		5,868		3,401
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	33,408	36,075	35,572	38,639
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	100	226	241	587
Land acquisition & development construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	12,922		12,922		15,503
Recorded Investment With No Allowance	4,774		4,774		7,245
Recorded Investment With Allowance	1,785		1,785		778
Total Recorded Investment	6,559		6,559		8,023
Related Allowance	828		828		282
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	6,797	9,325	6,992	9,591
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	13	29	32	51
Residential construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	977		977		992
Recorded Investment With No Allowance	266		266		293
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	266		266		293
Related Allowance	0		0		0
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	274	330	279	300
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	0	0	0	0
Commercial construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	1,154		1,154		1,264
Recorded Investment With No Allowance	232		232		340
Recorded Investment With Allowance	703		703		739
Total Recorded Investment	935		935		1,079
Related Allowance	737		737		739
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	1,055	2,339	1,007	1,902
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	1	4	3	6
Total construction loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	15,053		15,053		17,759
Recorded Investment With No Allowance	5,272		5,272		7,878
Recorded Investment With Allowance	2,488		2,488		1,517
Total Recorded Investment	7,760		7,760		9,395
Related Allowance	1,565		1,565		1,021
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	8,126	11,994	8,278	11,793
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	14	33	35	57
Residential real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	5,229		5,229		7,073
Recorded Investment With No Allowance	2,774		2,774		3,547
Recorded Investment With Allowance	1,043		1,043		2,317
Total Recorded Investment	3,817		3,817		5,864
Related Allowance	142		142		367
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	3,282	2,607	4,219	2,720
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	4	4	7	6
Agricultural real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	3,988		3,988		6,434
Recorded Investment With No Allowance	3,646		3,646		5,563
Recorded Investment With Allowance	26		26		198
Total Recorded Investment	3,672		3,672		5,761
Related Allowance	1		1		5
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	4,786	8,578	4,607	8,661
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	2	27	3	62
Total real estate loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	82,407		82,407		89,445
Recorded Investment With No Allowance	28,210		28,210		44,870
Recorded Investment With Allowance	33,008		33,008		21,646
Total Recorded Investment	61,218		61,218		66,516
Related Allowance	7,576		7,576		4,794
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	49,602	59,254	52,676	61,813
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	120	290	286	712
Commercial
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	39,349		39,349		29,593
Recorded Investment With No Allowance	15,296		15,296		10,744
Recorded Investment With Allowance	18,893		18,893		13,727
Total Recorded Investment	34,189		34,189		24,471
Related Allowance	10,912		10,912		6,487
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	30,123	22,483	27,781	18,175
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	72	2	128	122
Agricultural
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	3,925		3,925		1,349
Recorded Investment With No Allowance	3,294		3,294		622
Recorded Investment With Allowance	441		441		356
Total Recorded Investment	3,735		3,735		978
Related Allowance	77		77		$ 294
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	2,249	937	2,341	848
Impaired Financing Receivable, Interest Income, Cash Basis Method [Abstract]
Income Recognized	$ 0	$ 13	$ 0	$ 26

Schedule of Loans Renegotiated

Schedule of Loans Renegotiated in Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016USD ($)notes	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)notes	Sep. 30, 2015USD ($)	Dec. 31, 2015USD ($)
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Loans Renegotiated in Troubled Debt Restructurings	$ 44,704		$ 44,704		$ 40,330
Loans Renegotiated in Troubled Debt Restructurings, Non-Accrual Loans	27,541		27,541		24,911
Loans Renegotiated in Troubled Debt Restructurings, Accrual Loans	$ 17,163		$ 17,163		$ 15,419
Number of Notes | notes	6		23
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 2,009		$ 11,311
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 0	$ 0	$ 0	$ 0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | notes	0		1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	$ 0		$ 194
Loans and Leases Receivable, Impaired, Commitment to Lend	0		0
Interest only period
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		4,929
Extension of terms or maturity
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	1,026		2,298
Interest Rate Adjustment Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		46
Other Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 983		$ 4,038
Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Number of Notes | notes	4		11
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 1,824		$ 3,088
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | notes	0		1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	$ 0		$ 194
Commercial real estate | Interest only period
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		689
Commercial real estate | Extension of terms or maturity
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	841		1,166
Commercial real estate | Interest Rate Adjustment Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		0
Commercial real estate | Other Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 983		$ 1,233
Residential real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Number of Notes | notes	1		1
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 64		$ 64
Residential real estate | Interest only period
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		0
Residential real estate | Extension of terms or maturity
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	64		64
Residential real estate | Interest Rate Adjustment Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		0
Residential real estate | Other Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 0		$ 0
Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Number of Notes | notes			10
Financing Receivable, Modifications, Pre-Modification Recorded Investment			$ 8,038
Commercial | Interest only period
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			4,240
Commercial | Extension of terms or maturity
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			947
Commercial | Interest Rate Adjustment Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			46
Commercial | Other Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			$ 2,805
Agricultural
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Number of Notes | notes	1		1
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 121		$ 121
Agricultural | Interest only period
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		0
Agricultural | Extension of terms or maturity
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	121		121
Agricultural | Interest Rate Adjustment Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0		0
Agricultural | Other Concession [Member]
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 0		$ 0

Schedule of Recorded Investme51

Schedule of Recorded Investment in Criticized Loans by Class and Credit Quality Indicator (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	$ 5,462,936	$ 5,193,321
Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,843,120	1,793,258
Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	212,680	224,066
Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	137,014	111,763
Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	128,154	94,890
Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	477,848	430,719
Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,047,150	1,032,851
Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	172,949	156,234
Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	3,541,067	3,413,062
Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	731,901	622,529
Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	153,624	153,717
Credit card consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	66,860	68,107
Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	952,385	844,353
Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	814,392	792,416
Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	152,800	142,151
Other Assets Especially Mentioned
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	152,868	127,270
Other Assets Especially Mentioned | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	76,913	61,787
Other Assets Especially Mentioned | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	11,597	16,593
Other Assets Especially Mentioned | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,615	1,640
Other Assets Especially Mentioned | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,616	166
Other Assets Especially Mentioned | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	14,828	18,399
Other Assets Especially Mentioned | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	5,461	4,453
Other Assets Especially Mentioned | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	6,511	6,114
Other Assets Especially Mentioned | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	103,713	90,753
Other Assets Especially Mentioned | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	847	644
Other Assets Especially Mentioned | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	665	651
Other Assets Especially Mentioned | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,512	1,295
Other Assets Especially Mentioned | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	42,080	32,975
Other Assets Especially Mentioned | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	5,563	2,247
Substandard
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	175,555	162,785
Substandard | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	88,580	84,556
Substandard | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	7,377	12,482
Substandard | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,482	1,886
Substandard | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	5,891	323
Substandard | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	14,750	14,691
Substandard | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	13,195	9,661
Substandard | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	16,605	16,529
Substandard | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	133,130	125,437
Substandard | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,572	1,131
Substandard | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,130	1,130
Substandard | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,702	2,261
Substandard | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	31,931	27,982
Substandard | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	7,792	7,105
Doubtful
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	41,540	30,350
Doubtful | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	17,991	10,609
Doubtful | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,383	591
Doubtful | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	664	0
Doubtful | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	720	756
Doubtful | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,767	1,347
Doubtful | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	214	2,540
Doubtful | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	0	0
Doubtful | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	20,972	14,496
Doubtful | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	121	154
Doubtful | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	217	198
Doubtful | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	338	352
Doubtful | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	19,758	15,085
Doubtful | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	472	417
Total Criticized Loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	369,963	320,405
Total Criticized Loans | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	183,484	156,952
Total Criticized Loans | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	20,357	29,666
Total Criticized Loans | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	3,761	3,526
Total Criticized Loans | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	8,227	1,245
Total Criticized Loans | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	32,345	34,437
Total Criticized Loans | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	18,870	16,654
Total Criticized Loans | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	23,116	22,643
Total Criticized Loans | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	257,815	230,686
Total Criticized Loans | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,540	1,929
Total Criticized Loans | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,012	1,979
Total Criticized Loans | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	4,552	3,908
Total Criticized Loans | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	93,769	76,042
Total Criticized Loans | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	$ 13,827	$ 9,769

Schedule of Allowance for Loan

Schedule of Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Certain Loans and Debt Securities Acquired in Transfer, Allowance for Credit Losses Due to Subsequent Impairment					$ 433	$ 382
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 80,340	$ 76,552	$ 76,817	$ 74,200
Provision charged to operating expense	2,363	1,098	8,913	3,533
Less loans charged-off	(3,115)	(4,547)	(10,858)	(7,916)
Add back recoveries of loans previously charged-off	1,647	1,153	6,363	4,439
Ending balance	81,235	74,256	81,235	74,256
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Loans individually evaluated for impairment					18,565	11,575
Loans collectively evaluated for impairment					62,670	65,242
Ending balance	80,340	76,552	76,817	74,200	81,235	76,817
Total loans:
Individually evaluated for impairment					99,142	91,965
Individually evaluated for impairment					5,363,794	5,101,356
Total loans					5,462,936	5,193,321
Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	32,281	53,935	52,296	53,884
Provision charged to operating expense	(352)	(1,149)	(20,492)	(1,718)
Less loans charged-off	(379)	(2,219)	(2,824)	(3,014)
Add back recoveries of loans previously charged-off	221	389	2,791	1,804
Ending balance	31,771	50,956	31,771	50,956
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Loans individually evaluated for impairment					7,576	4,794
Loans collectively evaluated for impairment					24,195	47,502
Ending balance	32,281	53,935	52,296	53,884	31,771	52,296
Total loans:
Individually evaluated for impairment					61,218	66,516
Individually evaluated for impairment					3,479,849	3,346,546
Total loans					3,541,067	3,413,062
Total consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	6,315	5,828	5,144	5,035
Provision charged to operating expense	2,395	430	5,747	2,201
Less loans charged-off	(2,157)	(1,537)	(5,761)	(3,675)
Add back recoveries of loans previously charged-off	742	653	2,165	1,813
Ending balance	7,295	5,374	7,295	5,374
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Loans individually evaluated for impairment					0	0
Loans collectively evaluated for impairment					7,295	5,144
Ending balance	6,315	5,828	5,144	5,035	7,295	5,144
Total loans:
Individually evaluated for impairment					0	0
Individually evaluated for impairment					952,385	844,353
Total loans					952,385	844,353
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	39,995	15,797	18,775	14,307
Provision charged to operating expense	265	2,004	22,268	3,220
Less loans charged-off	(579)	(791)	(2,085)	(1,227)
Add back recoveries of loans previously charged-off	680	111	1,403	821
Ending balance	40,361	17,121	40,361	17,121
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Loans individually evaluated for impairment					10,912	6,487
Loans collectively evaluated for impairment					29,449	12,288
Ending balance	39,995	15,797	18,775	14,307	40,361	18,775
Total loans:
Individually evaluated for impairment					34,189	24,471
Individually evaluated for impairment					780,203	767,945
Total loans					814,392	792,416
Agriculture
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,749	992	602	974
Provision charged to operating expense	55	(187)	1,390	(170)
Less loans charged-off	0	0	(188)	0
Add back recoveries of loans previously charged-off	4	0	4	1
Ending balance	1,808	805	1,808	805
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Loans individually evaluated for impairment					77	294
Loans collectively evaluated for impairment					1,731	308
Ending balance	1,749	992	602	974	1,808	602
Total loans:
Individually evaluated for impairment					3,735	978
Individually evaluated for impairment					149,065	141,173
Total loans					152,800	142,151
Other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	0	0	0	0
Provision charged to operating expense	0	0	0	0
Less loans charged-off	0	0	0	0
Add back recoveries of loans previously charged-off	0	0	0	0
Ending balance	0	0	0	0
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Loans individually evaluated for impairment					0	0
Loans collectively evaluated for impairment					0	0
Ending balance	$ 0	$ 0	$ 0	$ 0	0	0
Total loans:
Individually evaluated for impairment					0	0
Individually evaluated for impairment					2,292	1,339
Total loans					$ 2,292	$ 1,339

OREO (Details)

OREO (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Real Estate Acquired Through Foreclosure, Acquired Through Acquisition	$ 1,120	$ 0	$ 1,120	$ 0
Mortgage Loans in Process of Foreclosure, Amount	0		0
Real Estate Acquired Through Foreclosure [Roll Forward]
Beginning balance	7,908	11,773	6,254	13,554
Additions	1,316	984	5,335	5,380
Valuation adjustments	0	(73)	(603)	(179)
Dispositions	(897)	(4,653)	(2,659)	(10,724)
Ending balance	9,447	$ 8,031	9,447	$ 8,031
Residential real estate
Real Estate Acquired Through Foreclosure [Roll Forward]
Beginning balance			1,686
Ending balance	$ 2,730		$ 2,730

Derivatives and Hedging (Detail

Derivatives and Hedging (Details) - USD ($) $ in Thousands	Sep. 22, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Derivative [Line Items]
Derivative, Inception Date	Sep. 22, 2015
Derivative, Fixed Interest Rate	1.94%
Derivative Asset, Notional Amount		$ 113,604		$ 113,604		$ 109,369
Interest Rate Derivative Assets, at Fair Value		4,167		4,167		953
Derivative Liability, Notional Amount	$ 100,000	277,021		277,021		9,369
Interest Rate Derivative Liabilities, at Fair Value		4,646		4,646		829
Interest Rate Swap
Derivative [Line Items]
Derivative Liability, Notional Amount						100,000
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion		512
Derivative Instruments, Loss Recognized in Other Comprehensive Income (Loss), Effective Portion			$ (436)	(2,490)	$ (436)
Designated as Hedging Instrument [Member] | Interest Rate Swap
Derivative [Line Items]
Derivative Asset, Notional Amount		0		0		100,000
Interest Rate Derivative Assets, at Fair Value		0		0		165
Derivative Liability, Notional Amount		100,000		100,000		0
Interest Rate Derivative Liabilities, at Fair Value		2,325		2,325		0
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Loss on Derivative		(3)	(31)	(82)	(48)
Fee Income on Derivatives		0	0	245	0
Gain (Loss) on Fair Value Hedges Recognized in Earnings		752	$ 0	1,970	$ 0
Not Designated as Hedging Instrument [Member] | Interest Rate Swap
Derivative [Line Items]
Derivative Asset, Notional Amount		20,757		20,757		9,369
Interest Rate Derivative Assets, at Fair Value		1,577		1,577		788
Derivative Liability, Notional Amount		20,757		20,757		9,369
Interest Rate Derivative Liabilities, at Fair Value		1,701		1,701		829
Not Designated as Hedging Instrument [Member] | Interest Rate Lock Commitments [Member]
Derivative [Line Items]
Derivative Asset, Notional Amount		92,847		92,847		0
Interest Rate Derivative Assets, at Fair Value		2,590		2,590		0
Not Designated as Hedging Instrument [Member] | Forward Contracts [Member]
Derivative [Line Items]
Derivative Liability, Notional Amount		156,264		156,264		0
Interest Rate Derivative Liabilities, at Fair Value		$ 620		$ 620		$ 0

Capital Stock (Details)

Capital Stock (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Class of Stock [Line Items]
Payments for Repurchase of Common Stock	$ 26,119	$ 20,548
Class A Common Stock
Class of Stock [Line Items]
Common Stock, Shares, Outstanding	21,459,481		21,698,594
Stock Repurchased and Retired During Period, Shares	975,877	765,875
Payments for Repurchase of Common Stock	$ 25,525	$ 19,921
Stock Repurchase Program, Remaining Authorized Repurchase Amount	24,123
Class B Common Stock
Class of Stock [Line Items]
Common Stock, Shares, Outstanding	23,420,517		23,729,631

Computation of Basic and Dilute

Computation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Net Income (Loss) Available to Common Stockholders, Basic
Net income	$ 25,193	$ 20,162	$ 70,871	$ 63,364
Weighted Average Number of Shares Outstanding, Basic and Diluted
Weighted average common shares outstanding for basic earnings per share computation	44,415,213	45,150,104	44,505,544	45,223,988
Dilutive effect of stock-based compensation	390,708	428,874	379,368	481,636
Weighted average common shares outstanding for diluted earnings per common share computation	44,805,921	45,578,978	44,884,912	45,705,624
Earnings Per Share, Basic and Diluted
Basic earnings per common share	$ 0.57	$ 0.45	$ 1.59	$ 1.40
Diluted earnings per common share	$ 0.56	$ 0.44	$ 1.58	$ 1.39
Performance Shares [Member]
Earnings Per Share, Basic and Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			218,556	165,489
Unvested Restricted Stock
Earnings Per Share, Basic and Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	135	5,884	95,886	5,884

Schedule of Actual Capital Amou

Schedule of Actual Capital Amounts and Ratios and Selected Minimum Regulatory Thresholds (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Total risk-based capital:
Actual Amount	$ 962,182	$ 946,156
Actual Ratio	14.90%	15.40%
Well Capitalized Amount	$ 647,138	$ 615,865
Well Capitalized Ratio	10.00%	10.00%
Tier 1 risk-based capital:
Actual Amount	$ 877,285	$ 861,339
Actual Ratio	13.60%	14.00%
Well Capitalized Amount	$ 517,711	$ 492,692
Well Capitalized Ratio	8.00%	8.00%
Common equity tier one risk-based capital:
Actual Amount	$ 797,285	$ 781,339
Actual Ratio	12.30%	12.70%
Leverage capital ratio:
Actual Amount	$ 877,285	$ 861,339
Actual Ratio	10.20%	10.10%
Adequately Capitalized Amount	$ 343,228	$ 340,480
Adequately Capitalized Ratio	4.00%	4.00%
Well Capitalized Amount	$ 429,035	$ 425,600
Well Capitalized Ratio	5.00%	5.00%
Capital Required for Capital Adequacy under Basel III Phase-in Schedule	$ 558,157	$ 492,692
Capital Required for Capital Adequacy under Basel III Phase-in Schedule to Risk Weighted Assets	8.60%	8.00%
Capital Required for Capital Adequacy under Basel III Fully Phased-in	$ 679,495	$ 646,658
Capital Required for Capital Adequacy under Basel III Fully Phased-in to Risk Weighted Assets	10.50%	10.50%
Tier One Risk Based Capital under Basel III Phase-in Schedule	$ 428,729	$ 369,519
Tier One Capital Required for Capital Adequacy under Basel III Phase-in Schedule to Risk Weighted Assets	6.60%	6.00%
Tier One Capital Required for Capital Adequacy under Basel III Fully Phased-in	$ 550,068	$ 523,485
Tier One Capital Required for Capital Adequacy under Basel III Fully Phased-in to Risk Weighted Assets	8.50%	8.50%
Common Equity Tier One Capital Required for Capital Adequacy under Basel III Phase-in Schedule	$ 331,658	$ 277,139
Common Equity Tier One Capital Required for Capital Adequacy under Basel III Phase-in Schedule to Risk Weighted Assets	5.10%	4.50%
Tier One Common Equity Capital Required for Capital Adequacy under Basel III Fully Phased-in	$ 452,997	$ 431,105
Tier One Common Equity Capital Required for Capital Adequacy under Basel III Fully Phased-in to Risk Weighted Assets	7.00%	7.00%
Common Equity Tier One Capital to be Well Capitalized	$ 420,640	$ 400,312
Common Equity Tier One Capital to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%
FIB
Total risk-based capital:
Actual Amount	$ 898,288	$ 882,504
Actual Ratio	13.90%	14.40%
Well Capitalized Amount	$ 644,816	$ 613,582
Well Capitalized Ratio	10.00%	10.00%
Tier 1 risk-based capital:
Actual Amount	$ 817,678	$ 805,805
Actual Ratio	12.70%	13.10%
Well Capitalized Amount	$ 515,853	$ 490,866
Well Capitalized Ratio	8.00%	8.00%
Common equity tier one risk-based capital:
Actual Amount	$ 817,678	$ 805,805
Actual Ratio	12.70%	13.10%
Leverage capital ratio:
Actual Amount	$ 817,678	$ 805,805
Actual Ratio	9.50%	9.50%
Adequately Capitalized Amount	$ 342,629	$ 339,316
Adequately Capitalized Ratio	4.00%	4.00%
Well Capitalized Amount	$ 428,286	$ 424,145
Well Capitalized Ratio	5.00%	5.00%
Capital Required for Capital Adequacy under Basel III Phase-in Schedule	$ 556,154	$ 490,866
Capital Required for Capital Adequacy under Basel III Phase-in Schedule to Risk Weighted Assets	8.60%	8.00%
Capital Required for Capital Adequacy under Basel III Fully Phased-in	$ 677,057	$ 644,262
Capital Required for Capital Adequacy under Basel III Fully Phased-in to Risk Weighted Assets	10.50%	10.50%
Tier One Risk Based Capital under Basel III Phase-in Schedule	$ 427,191	$ 368,149
Tier One Capital Required for Capital Adequacy under Basel III Phase-in Schedule to Risk Weighted Assets	6.60%	6.00%
Tier One Capital Required for Capital Adequacy under Basel III Fully Phased-in	$ 548,094	$ 521,545
Tier One Capital Required for Capital Adequacy under Basel III Fully Phased-in to Risk Weighted Assets	8.50%	8.50%
Common Equity Tier One Capital Required for Capital Adequacy under Basel III Phase-in Schedule	$ 330,468	$ 276,112
Common Equity Tier One Capital Required for Capital Adequacy under Basel III Phase-in Schedule to Risk Weighted Assets	5.10%	4.50%
Tier One Common Equity Capital Required for Capital Adequacy under Basel III Fully Phased-in	$ 451,371	$ 429,508
Tier One Common Equity Capital Required for Capital Adequacy under Basel III Fully Phased-in to Risk Weighted Assets	7.00%	7.00%
Common Equity Tier One Capital to be Well Capitalized	$ 419,131	$ 398,829
Common Equity Tier One Capital to be Well Capitalized to Risk Weighted Assets	6.50%	6.50%

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015	Sep. 22, 2015
Loss Contingencies [Line Items]
Derivative Liability, Notional Amount	$ 277,021	$ 9,369	$ 100,000
Commitments to Complete Contracts in Process	527
Interest Rate Swap
Loss Contingencies [Line Items]
Derivative Liability, Notional Amount		$ 100,000
Mortgage Loans Held for Sale
Loss Contingencies [Line Items]
Guarantor Obligations, Recourse Provisions	2,912

Financial Instruments with Of59

Financial Instruments with Off-Balance Sheet Risk (Details) $ in Thousands	Sep. 30, 2016USD ($)
Entity Information [Line Items]
Credit Extension Commitments	$ 1,604,619
Credit Extension Commitments, Beyond One Year	419,638
Standby Letters of Credit
Entity Information [Line Items]
Credit Extension Commitments	54,424
Unused Credit Card Lines
Entity Information [Line Items]
Credit Extension Commitments	$ 545,399

Schedule of Comprehensive Incom

Schedule of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Change in net unrealized Gain during period:
Change in net unrealized gain during period, before tax amount	$ (3,430)	$ 10,855	$ 15,241	$ 12,264
Change in net unrealized gain during period, tax expense (benefit)	(1,359)	4,272	5,963	4,827
Change in net unrealized gain during period, net of tax amount	(2,071)	6,583	9,278	7,437
Reclassification adjustment for gains included in net income:
Reclassification adjustment for gains included in net income, before tax amount	(225)	(23)	(312)	(75)
Reclassification adjustment for gains included in net income, tax expense (benefit)	(89)	(10)	(123)	(30)
Reclassification adjustment for gains included in net income, net of tax amount	(136)	(13)	(189)	(45)
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	490	448	1,394	1,353
Other Comprehensive Income (Loss), Transfers from Held-to-maturity to Available-for-Sale Securities, Tax	209	177	549	532
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	281	271	845	821
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	512	(436)	(2,490)	(436)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	195	(172)	(946)	(172)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	317	(264)	(1,544)	(264)
Change in net actuarial loss:
Change in net actuarial loss, before tax amount	15	15	43	43
Change in net actuarial loss, tax expense (benefit)	6	6	17	17
Change in net actuarial loss, net of tax amount	9	9	26	26
Other comprehensive income (loss):
Other comprehensive income (loss), before tax	(2,638)	10,859	13,876	13,149
Total other comprehensive income, tax expense (benefit)	(1,038)	4,273	5,460	5,174
Total other comprehensive income, net of tax amount	$ (1,600)	$ 6,586	$ 8,416	$ 7,975

Schedule of Accumulated Other C

Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Net accumulated other comprehensive income:
Net unrealized gain on investment securities available-for-sale	$ 10,618	$ 684
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	(1,444)	100
Net actuarial loss on defined benefit post-retirement benefit plans	(352)	(378)
Net accumulated other comprehensive income	$ 8,822	$ 406

Schedule of Financial Assets an

Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring and Non-Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real Estate Acquired Through Foreclosure, Valuation Adjustments	$ 0	$ 73	$ 603	$ 179
Related Allowance	18,565		18,565		$ 11,575
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	0		0
Deferred compensation asset at fair value amount	0		0		0
Deferred compensation plan liabilities at fair value amount	0		0		0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0		0		0
Other real estate owned	0		0		0
Long-lived assets to be disposed of by sale	0		0		0
Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	67,979		67,979
Deferred compensation asset at fair value amount	10,534		10,534		10,149
Deferred compensation plan liabilities at fair value amount	10,534		10,534		10,149
Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0		0		0
Other real estate owned	0		0		0
Long-lived assets to be disposed of by sale	0		0		0
Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	0		0
Deferred compensation asset at fair value amount	0		0		0
Deferred compensation plan liabilities at fair value amount	0		0		0
Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans					20,875
Other real estate owned	2,808		2,808		1,789
Real Estate Acquired Through Foreclosure, Valuation Adjustments			603
Impairment of real estate, received updated appraisal			550
Impairment of Real Estate, Change in Management Estimates			53	$ 73
Long-lived assets to be disposed of by sale	1,506		1,506		1,506
Related Allowance	18,565		18,565		11,575
Impaired Financing Receivable, Related Allowance, Partial Loan Charge-Offs	10,422		10,422		10,229
US Treasury Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
US Treasury Securities [Member] | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	3,639		3,639		3,911
US Treasury Securities [Member] | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Obligations of U.S. government agencies | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Obligations of U.S. government agencies | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	441,127		441,127		520,181
Obligations of U.S. government agencies | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,083,369		1,083,369		929,046
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Private mortgage-backed securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Private mortgage-backed securities | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	124		124		156
Private mortgage-backed securities | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Other Investments | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Other Investments | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	4,962		4,962		3,546
Other Investments | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,533,221		1,533,221		1,456,840
Loans Receivable, Fair Value Disclosure	5,321,409		5,321,409		5,128,705
Derivative Asset	4,167		4,167		953
Derivative Liability	4,646		4,646		829
Mortgages Held-for-sale, Fair Value Disclosure	67,979		67,979
Deferred compensation asset at fair value amount	10,534		10,534		10,149
Deferred compensation plan liabilities at fair value amount	10,534		10,534		10,149
Estimated Fair Value | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	67,979		67,979
Deferred compensation asset at fair value amount	10,534		10,534		10,149
Deferred compensation plan liabilities at fair value amount	10,534		10,534		10,149
Estimated Fair Value | Fair Value Measured on a Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	39,746		39,746		20,875
Other real estate owned	2,808		2,808		1,789
Long-lived assets to be disposed of by sale	1,506		1,506		1,506
Estimated Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Loans Receivable, Fair Value Disclosure	0		0		0
Derivative Asset	0		0		0
Derivative Liability	0		0		0
Mortgages Held-for-sale, Fair Value Disclosure	0		0
Deferred compensation asset at fair value amount	0		0		0
Deferred compensation plan liabilities at fair value amount	0		0		0
Estimated Fair Value | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,533,221		1,533,221		1,456,840
Loans Receivable, Fair Value Disclosure	5,281,663		5,281,663		5,107,830
Derivative Asset	4,167		4,167		953
Derivative Liability	4,646		4,646		829
Mortgages Held-for-sale, Fair Value Disclosure	67,979		67,979
Deferred compensation asset at fair value amount	10,534		10,534		10,149
Deferred compensation plan liabilities at fair value amount	10,534		10,534		10,149
Estimated Fair Value | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	0		0		0
Loans Receivable, Fair Value Disclosure	39,746		39,746		20,875
Derivative Asset	0		0		0
Derivative Liability	0		0		0
Mortgages Held-for-sale, Fair Value Disclosure	0		0
Deferred compensation asset at fair value amount	0		0		0
Deferred compensation plan liabilities at fair value amount	0		0		0
Estimated Fair Value | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	39,746		39,746		20,875
Estimated Fair Value | US Treasury Securities [Member] | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	3,639		3,639		3,911
Estimated Fair Value | Obligations of U.S. government agencies | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	441,127		441,127		520,181
Estimated Fair Value | U.S. agency residential mortgage-backed securities & collateralized mortgage obligations | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,083,369		1,083,369		929,046
Estimated Fair Value | Private mortgage-backed securities | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	124		124		156
Estimated Fair Value | Other Investments | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	4,962		4,962		3,546
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,533,221		1,533,221		1,456,840
Loans Receivable, Fair Value Disclosure	5,462,936		5,462,936		5,169,379
Derivative Asset	4,167		4,167		953
Derivative Liability	4,646		4,646		829
Mortgages Held-for-sale, Fair Value Disclosure	67,979		67,979
Deferred compensation asset at fair value amount	10,534		10,534		10,149
Deferred compensation plan liabilities at fair value amount	10,534		10,534		10,149
Carrying Amount | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	68,733		68,733		42,679
Long-lived assets to be disposed of by sale	2,363		2,363		2,363
Change During Period | Fair Value Measured on a Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-lived assets to be disposed of by sale	857		857		857
Interest Rate Swap | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0		0
Derivative Liability	0		0		0
Interest Rate Swap | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	1,577		1,577		953
Derivative Liability	4,026		4,026		829
Interest Rate Swap | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0		0
Derivative Liability	0		0		0
Interest Rate Swap | Estimated Fair Value | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	1,577		1,577		953
Derivative Liability	4,026		4,026		$ 829
Interest Rate Lock Commitments [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0
Interest Rate Lock Commitments [Member] | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	2,590		2,590
Interest Rate Lock Commitments [Member] | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0
Interest Rate Lock Commitments [Member] | Estimated Fair Value | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	2,590		2,590
Forward Contracts [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0		0
Forward Contracts [Member] | Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	620		620
Forward Contracts [Member] | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0		0
Forward Contracts [Member] | Estimated Fair Value | Fair Value Measured on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	$ 620		$ 620

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Inputs, Quantitative Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Loans and Leases Receivable, Impaired Loans | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(0.00%)
Loans and Leases Receivable, Impaired Loans | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(53.00%)
Loans and Leases Receivable, Impaired Loans | Weighted Average | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(38.00%)
Real Estate Acquired in Satisfaction of Debt | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(2.00%)
Real Estate Acquired in Satisfaction of Debt | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(96.00%)
Real Estate Acquired in Satisfaction of Debt | Weighted Average | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(19.00%)
Asses to be Disposed of by Sale | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(0.00%)
Asses to be Disposed of by Sale | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(9.00%)
Asses to be Disposed of by Sale | Weighted Average | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(6.00%)
Carrying Amount
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	$ 5,462,936	$ 5,169,379
Change During Period | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Long-lived assets to be disposed of by sale	857	857
Estimated Fair Value
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	5,321,409	5,128,705
Estimated Fair Value | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	39,746	20,875
Long-lived assets to be disposed of by sale	1,506	1,506
Other real estate owned	2,808	1,789
Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans		20,875
Long-lived assets to be disposed of by sale	1,506	1,506
Other real estate owned	2,808	1,789
Significant Unobservable Inputs (Level 3) | Carrying Amount | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	68,733	42,679
Long-lived assets to be disposed of by sale	2,363	2,363
Significant Unobservable Inputs (Level 3) | Estimated Fair Value
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	39,746	20,875
Significant Unobservable Inputs (Level 3) | Estimated Fair Value | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	$ 39,746	$ 20,875

Schedule of Estimated Fair Valu

Schedule of Estimated Fair Values of Financial Instruments by Level of Valuation Inputs (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financial assets:
Investment securities held-to-maturity	$ 554,048	$ 607,550
Carrying Amount
Financial assets:
Cash and cash equivalents	701,367	780,457
Investment securities available-for-sale	1,533,221	1,456,840
Investment securities held-to-maturity	539,052	600,665
Accrued interest receivable	31,002	27,729
Mortgage servicing rights	17,322	15,621
Mortgages Held-for-sale, Fair Value Disclosure	67,979
Loans Receivable, Fair Value Disclosure	5,462,936	5,169,379
Derivative Asset	4,167	953
Deferred compensation asset at fair value amount	10,534	10,149
Total financial assets	8,367,580	8,061,793
Financial liabilities:
Total deposits, excluding time deposits	6,235,993	5,957,345
Time deposits	1,092,588	1,131,592
Securities sold under repurchase agreements	476,768	510,635
Other borrowed funds	8	2
Accrued interest payable	5,622	4,960
Long-term debt	27,949	27,885
Subordinated debentures held by subsidiary trusts	82,477	82,477
Derivative Liability	4,646	829
Deferred compensation plan liabilities at fair value amount	10,534	10,149
Total financial liabilities	7,936,585	7,725,874
Estimated Fair Value
Financial assets:
Cash and cash equivalents	701,367	780,457
Investment securities available-for-sale	1,533,221	1,456,840
Investment securities held-to-maturity	554,048	607,550
Accrued interest receivable	31,002	27,729
Mortgage servicing rights	25,845	31,011
Mortgages Held-for-sale, Fair Value Disclosure	67,979
Loans Receivable, Fair Value Disclosure	5,321,409	5,128,705
Derivative Asset	4,167	953
Deferred compensation asset at fair value amount	10,534	10,149
Total financial assets	8,249,572	8,043,394
Financial liabilities:
Total deposits, excluding time deposits	6,235,993	5,975,345
Time deposits	1,090,434	1,137,289
Securities sold under repurchase agreements	476,768	510,635
Other borrowed funds	8	2
Accrued interest payable	5,622	4,960
Long-term debt	27,801	27,622
Subordinated debentures held by subsidiary trusts	72,803	74,969
Derivative Liability	4,646	829
Deferred compensation plan liabilities at fair value amount	10,534	10,149
Total financial liabilities	7,924,609	7,741,800
Quoted Prices in Active Markets for Identical Assets (Level 1) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	701,367	780,457
Investment securities available-for-sale	0	0
Investment securities held-to-maturity	0	0
Accrued interest receivable	0	0
Mortgage servicing rights	0	0
Mortgages Held-for-sale, Fair Value Disclosure	0
Loans Receivable, Fair Value Disclosure	0	0
Derivative Asset	0	0
Deferred compensation asset at fair value amount	0	0
Total financial assets	701,367	780,457
Financial liabilities:
Total deposits, excluding time deposits	6,235,993	5,975,345
Time deposits	0	0
Securities sold under repurchase agreements	0	0
Other borrowed funds	0	0
Accrued interest payable	0	0
Long-term debt	0	0
Subordinated debentures held by subsidiary trusts	0	0
Derivative Liability	0	0
Deferred compensation plan liabilities at fair value amount	0	0
Total financial liabilities	6,235,993	5,975,345
Significant Other Observable Inputs (Level 2) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	0	0
Investment securities available-for-sale	1,533,221	1,456,840
Investment securities held-to-maturity	554,048	607,550
Accrued interest receivable	31,002	27,729
Mortgage servicing rights	25,845	31,011
Mortgages Held-for-sale, Fair Value Disclosure	67,979
Loans Receivable, Fair Value Disclosure	5,281,663	5,107,830
Derivative Asset	4,167	953
Deferred compensation asset at fair value amount	10,534	10,149
Total financial assets	7,508,459	7,242,062
Financial liabilities:
Total deposits, excluding time deposits	0	0
Time deposits	1,090,434	1,137,289
Securities sold under repurchase agreements	476,768	510,635
Other borrowed funds	8	2
Accrued interest payable	5,622	4,960
Long-term debt	27,801	27,622
Subordinated debentures held by subsidiary trusts	72,803	74,969
Derivative Liability	4,646	829
Deferred compensation plan liabilities at fair value amount	10,534	10,149
Total financial liabilities	1,688,616	1,766,455
Significant Unobservable Inputs (Level 3) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	0	0
Investment securities available-for-sale	0	0
Investment securities held-to-maturity	0	0
Accrued interest receivable	0	0
Mortgage servicing rights	0	0
Mortgages Held-for-sale, Fair Value Disclosure	0
Loans Receivable, Fair Value Disclosure	39,746	20,875
Derivative Asset	0	0
Deferred compensation asset at fair value amount	0	0
Total financial assets	39,746	20,875
Financial liabilities:
Total deposits, excluding time deposits	0	0
Time deposits	0	0
Securities sold under repurchase agreements	0	0
Other borrowed funds	0	0
Accrued interest payable	0	0
Long-term debt	0	0
Subordinated debentures held by subsidiary trusts	0	0
Derivative Liability	0	0
Deferred compensation plan liabilities at fair value amount	0	0
Total financial liabilities	$ 0	$ 0

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares	Nov. 14, 2016	Oct. 31, 2016	Oct. 21, 2016	Jul. 24, 2015
Class A Common Stock | Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends Payable, Date Declared			Oct. 21, 2016
Dividends Payable, Amount Per Share	$ 0.22
Dividends Payable, Date to be Paid	Nov. 14, 2016
Dividends Payable, Date of Record		Oct. 31, 2016
United Bank
Subsequent Event [Line Items]
Business Acquisition, Effective Date of Acquisition				Jul. 24, 2015