First Interstate BancSystem (FIBK) 10-Q 6 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - Jun. 30, 2015 - shares	Total
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	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Amendment Flag	false
Class A Common Stock
Entity Common Stock, Shares Outstanding	21,720,287
Class B Common Stock
Entity Common Stock, Shares Outstanding	23,786,296

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Assets
Cash and due from banks	$ 163,057	$ 147,894
Federal funds sold	2,763	543
Interest bearing deposits in banks	340,614	650,233
Total cash and cash equivalents	506,434	798,670
Investment securities:
Available-for-sale	1,592,743	1,711,924
Held-to-maturity (estimated fair values of $553,323 and $584,533 at June 30, 2015 and December 31, 2014, respectively)	546,690	575,186
Total investment securities	2,139,433	2,287,110
Loans held for investment	5,028,624	4,856,615
Mortgage loans held for sale	75,322	40,828
Total loans	5,103,946	4,897,443
Less allowance for loan losses	76,552	74,200
Net loans	5,027,394	4,823,243
Goodwill	204,375	205,574
Premises and equipment, net of accumulated depreciation	189,488	195,212
Company-owned life insurance	177,625	153,821
Other real estate owned (OREO)	11,773	13,554
Accrued interest receivable	29,008	27,063
Core deposit intangibles, net of accumulated amortization	11,573	13,282
Mortgage servicing rights, net of accumulated amortization and impairment reserve	14,654	14,038
Deferred tax asset, net	0	4,874
Other assets	74,461	73,495
Total assets	8,386,218	8,609,936
Deposits:
Non-interest bearing	1,757,641	1,791,364
Interest bearing	5,046,760	5,214,848
Total deposits	6,804,401	7,006,212
Securities sold under repurchase agreements	469,145	502,250
Accounts payable and accrued expenses	53,879	66,164
Accrued interest payable	5,366	5,833
Deferred tax liability	3,024	0
Long-term debt	43,068	38,067
Other borrowed funds	3	9
Subordinated debentures held by subsidiary trusts	82,477	82,477
Total liabilities	7,461,363	7,701,012
Stockholders' equity:
Nonvoting noncumulative preferred stock without par value; authorized 100,000 shares; no shares issued and outstanding as of June 30, 2015 or December 31, 2014	0	0
Common stock	313,125	323,596
Retained earnings	612,875	587,862
Accumulated other comprehensive income, net	(1,145)	(2,534)
Total stockholders' equity	924,855	908,924
Total liabilities and stockholders' equity	$ 8,386,218	$ 8,609,936

Consolidated Balance Sheets (U3

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Investment securities:
Held-to-Maturity, Estimated Fair Value	$ 553,323	$ 584,533
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		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Interest income:
Interest and fees on loans	$ 60,402	$ 55,565	$ 119,773	$ 109,283
Interest and dividends on investment securities:
Taxable	8,000	7,309	15,971	14,949
Exempt from federal taxes	1,040	1,083	2,099	2,180
Interest on deposits in banks	271	225	660	456
Interest on federal funds sold	5	3	7	4
Total interest income	69,718	64,185	138,510	126,872
Interest expense:
Interest on deposits	3,239	3,327	6,548	6,751
Interest on securities sold under repurchase agreements	53	63	107	129
Interest on long-term debt	538	476	1,052	949
Interest on subordinated debentures held by subsidiary trusts	600	592	1,190	1,180
Total interest expense	4,430	4,458	8,897	9,009
Net interest income	65,288	59,727	129,613	117,863
Provision for loan losses	1,340	(2,001)	2,435	(7,001)
Net interest income after provision for loan losses	63,948	61,728	127,178	124,864
Non-interest income:
Other service charges, commissions and fees	11,173	9,699	21,040	18,855
Income from the origination and sale of loans	8,802	6,380	14,708	11,040
Investment Advisory, Management and Administrative Fees	4,897	4,609	9,834	9,064
Service charges on deposit accounts	4,053	3,929	7,997	7,804
Investment securities gains, net	46	17	52	88
Other income	2,799	1,937	5,921	3,826
Total non-interest income	31,770	26,571	59,552	50,677
Non-interest expense:
Salaries and wages	26,093	24,440	51,442	46,882
Employee benefits	8,070	7,164	15,850	15,477
Occupancy, net	4,529	4,253	9,021	8,492
Furniture and equipment	3,703	3,157	7,496	6,358
Outsourced technology services	2,593	2,309	5,056	4,609
OREO expense, net of income	(823)	(134)	(884)	(153)
Professional fees	1,514	1,278	2,815	2,648
FDIC insurance premiums	1,304	1,093	2,446	2,209
Mortgage servicing rights amortization	627	583	1,246	1,183
Mortgage servicing rights impairment recovery	(56)	(11)	(71)	(56)
Core deposit intangibles amortization	854	354	1,709	708
Other expenses	13,577	10,837	25,381	21,304
Non-core acquisition expenses	(7)	597	63	597
Total non-interest expense	61,978	55,920	121,570	110,258
Income before income tax expense	33,740	32,379	65,160	65,283
Income tax expense	11,518	11,302	21,958	22,813
Net income	$ 22,222	$ 21,077	$ 43,202	$ 42,470
Basic earnings per common share	$ 0.49	$ 0.48	$ 0.95	$ 0.96
Diluted earnings per common share	$ 0.49	$ 0.47	$ 0.94	$ 0.95

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net income	$ 22,222	$ 21,077	$ 43,202	$ 42,470
Other comprehensive income (loss), before tax:
Change in net unrealized gains/losses during period	(9,196)	2,816	1,412	17,167
Reclassification adjustment for net (gains) losses included in income	(46)	(17)	(52)	(88)
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	451	0	902	0
Defined benefit post-retirement benefits plans:
Change in net actuarial loss	13	35	28	70
Other comprehensive income (loss), before tax	(8,778)	2,834	2,290	17,149
Deferred tax benefit (expense) related to other comprehensive income	3,454	(1,115)	(901)	(6,748)
Other comprehensive income (loss), net of tax	(5,324)	1,719	1,389	10,401
Comprehensive income, net of tax	$ 16,898	$ 22,796	$ 44,591	$ 52,871

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, 2013	$ 801,581	$ 285,535	$ 532,087	$ (16,041)
Comprehensive income:
Net income	42,470	0	42,470	0
Other comprehensive income, net of tax	10,401	0	0	10,401
Common stock transactions:
Common shares purchased and retired 588,409 and 349,930 in 2015 and 2014, respectively	(8,764)	(8,764)	0	0
Stock Issued During Period, 21,414 and 24,581 in 2015 and 2014, respectively	0	0	0	0
Non-vested common shares issued 156,956 and 147,876 in 2015 and 2014 respectively	0	0	0	0
1,678 and 8,647 non-vested common shares forfeited in 2015 and 2014 respectively	0	0	0	0
129,885 and 286,069 stock options exercised, net of 37,357 and 160,377 shares tendered in payment of option price and income tax withholding amounts in 2015 and 2014 respectively	3,547	3,547	0	0
Tax benefit of stock-based compensation	1,225	1,225	0	0
Stock-based compensation expense	2,154	2,154	0	0
Cash dividends declared:
Common ($0.40 per share) in 2015 and ($0.32 per share) in 2014	(14,088)	0	(14,088)	0
Ending Balance at Jun. 30, 2014	838,526	283,697	560,469	(5,640)
Beginning Balance at Dec. 31, 2014	908,924	323,596	587,862	(2,534)
Comprehensive income:
Net income	43,202	0	43,202	0
Other comprehensive income, net of tax	1,389	0	0	1,389
Common stock transactions:
Common shares purchased and retired 588,409 and 349,930 in 2015 and 2014, respectively	(15,264)	(15,264)	0	0
Stock Issued During Period, 21,414 and 24,581 in 2015 and 2014, respectively	0	0	0	0
Non-vested common shares issued 156,956 and 147,876 in 2015 and 2014 respectively	0	0	0	0
1,678 and 8,647 non-vested common shares forfeited in 2015 and 2014 respectively	0	0	0	0
129,885 and 286,069 stock options exercised, net of 37,357 and 160,377 shares tendered in payment of option price and income tax withholding amounts in 2015 and 2014 respectively	1,670	1,670	0	0
Tax benefit of stock-based compensation	804	804	0	0
Stock-based compensation expense	2,319	2,319	0	0
Cash dividends declared:
Common ($0.40 per share) in 2015 and ($0.32 per share) in 2014	(18,189)	0	(18,189)	0
Ending Balance at Jun. 30, 2015	$ 924,855	$ 313,125	$ 612,875	$ (1,145)

Consolidated Statements of Cha7

Consolidated Statements of Changes in Stockholders Equity (Unaudited) (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Common stock
Common stock transactions:
Common shares purchased and retired	588,409	349,930
Common shares issued	21,414	24,581
Non-vested common shares issued	156,956	147,876
Non-vested common shares forfeited	1,678	8,647
Stock options exercised	129,885	286,069
Shares tendered in payment of option price and income tax withholding amounts	37,357	160,377
Retained earnings
Cash dividends declared:
Common (in dollars per share)	$ 0.40	$ 0.32

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net income	$ 43,202	$ 42,470
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	2,435	(7,001)
Net (gain) loss on disposal of property and equipment	(856)	(79)
Depreciation and amortization	9,090	7,786
Net premium amortization on investment securities	7,021	7,088
Net gains on investment securities transactions	(52)	(88)
Net gains on sales of mortgage loans held for sale	(10,759)	(7,601)
Net gain on sale of OREO	(1,736)	(766)
Write-downs of OREO and other assets pending disposal	106	10
Net reversal of impairment of mortgage servicing rights	(71)	(56)
Deferred income tax expense	9,108	3,760
Net increase in cash surrender value of company-owned life insurance policies	(1,304)	(1,724)
Stock-based compensation expense	2,319	2,154
Tax benefits from stock-based compensation expense	804	1,225
Excess tax benefits from stock-based compensation	(530)	(1,211)
Originations of loans held for sale	(561,779)	(412,050)
Proceeds from sales of loans held for sale	546,871	402,825
Changes in operating assets and liabilities:
Increase in interest receivable	(1,945)	(47)
Increase in other assets	(1,034)	(1,929)
Decrease in accrued interest payable	(467)	353
Decrease in accounts payable and accrued expenses	(12,268)	(4,788)
Net cash provided by operating activities	28,155	30,331
Cash flows from investing activities:
Purchases of held-to-maturity investment securities	(27,640)	(4,141)
Purchases of available-for-sale investment securities	(223,483)	(175,823)
Proceeds from maturities and paydowns of held-to-maturity investment securities	55,654	9,347
Proceeds from maturities and paydowns of available-for-sale investment securities	337,538	243,355
Purchases of company-owned life insurance	(22,500)	(15,000)
Proceeds from sales of mortgage servicing rights	0	266
Extensions of credit to customers, net of repayments	(190,392)	(155,523)
Recoveries of loans charged-off	3,285	5,345
Proceeds from sales of OREO	7,807	4,234
Capital expenditures, net of sales	514	(6,309)
Net cash used in investing activities	(59,217)	(94,249)
Cash flows from financing activities:
Net increase (decrease) in deposits	(201,811)	45,292
Net increase (decrease) in repurchase agreements	(33,105)	5,548
Net increase (decrease) in other borrowed funds	(6)	17
Repayments of long-term debt	(30)	(24)
Advances on long-term debt	5,031	0
Proceeds from issuance of common stock	1,670	3,547
Excess tax benefits from stock-based compensation	530	1,211
Purchase and retirement of common stock	(15,264)	(8,764)
Dividends paid to common stockholders	(18,189)	(14,088)
Net cash provided by (used in) financing activities	(261,174)	32,739
Net increase (decrease) in cash and cash equivalents	(292,236)	(31,179)
Cash and cash equivalents at beginning of period	798,670	534,827
Cash and cash equivalents at end of period	506,434	503,648
Supplemental disclosures of cash flow information:
Cash paid during the period for income taxes	18,450	16,190
Cash paid during the period for interest expense	$ 9,364	$ 8,656

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2015
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 June 30, 2015 and December 31, 2014 , and the results of operations for each of the three and six month periods ended and cash flows for each of the six month periods ended June 30, 2015 and 2014 in conformity with U.S. generally accepted accounting principles. The balance sheet information at December 31, 2014 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 June 30, 2015 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, 2014 . Operating results for the three and six months ended June 30, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 .

Acquisitions

Acquisitions	6 Months Ended
	Jun. 30, 2015
Business Combinations [Abstract]
Acquisitions	Acquisitions Absarokee Bancorporation, Inc. On March 26, 2015 , the Company entered into an agreement and plan of merger to acquire all of the outstanding stock of Absarokee Bancorporation, Inc. ("Absarokee"), a Montana-based bank holding company that operates one subsidiary bank, United Bank, with branches located in three Montana communities adjacent to the Company's existing market areas. The acquisition was completed on July 24, 2015 for cash consideration of $ 7,234 . Immediately subsequent to the acquisition, United Bank was merged with and into the Company's existing bank subsidiary, First Interstate Bank ("FIB"). As of the date of the acquisition, Absarokee has total assets of approximately $73,272 , loans of approximately $37,520 and deposits of approximately $63,580 . Mountain West Financial Corp. On July 31, 2014 , the Company acquired all of the outstanding stock of Mountain West Financial Corp ("MWFC"), a Montana-based bank holding company operating one subsidiary bank, Mountain West Bank, NA ("MWB"). MWB was merged with and into FIB in October 2014 . During March 2015 , the Company completed its review of MWFC tax items and finalized the fair value of acquired deferred tax assets. Finalization of provisional estimates resulted in a $ 1,199 decrease in goodwill.

Investment Securities

Investment Securities	6 Months Ended
	Jun. 30, 2015
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities The amortized cost and approximate fair values of investment securities are summarized as follows: June 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: Obligations of U.S. government agencies $ 622,237 $ 1,087 $ (2,304 ) $ 621,020 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 965,430 10,468 (4,463 ) 971,435 Private mortgage-backed securities 286 4 (2 ) 288 Total $ 1,587,953 $ 11,559 $ (6,769 ) $ 1,592,743 June 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 181,642 $ 4,644 $ (524 ) $ 185,762 Corporate securities 50,310 59 (204 ) 50,165 U.S agency residential mortgage-backed securities & collateralized mortgage obligations 314,326 5,945 (3,288 ) 316,983 Other investments 412 1 — 413 Total $ 546,690 $ 10,649 $ (4,016 ) $ 553,323 December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: Obligations of U.S. government agencies $ 725,408 $ 895 $ (5,370 ) $ 720,933 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 982,764 11,526 (3,624 ) 990,666 Private mortgage-backed securities 322 5 (2 ) 325 Total $ 1,708,494 $ 12,426 $ (8,996 ) $ 1,711,924 December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 188,941 $ 5,949 $ (386 ) $ 194,504 Corporate securities 32,565 54 (75 ) 32,544 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 353,176 5,563 (1,758 ) 356,981 Other Investments 504 — — 504 Total $ 575,186 $ 11,566 $ (2,219 ) $ 584,533 Gross realized gains and losses from the disposition of investment securities are summarized in the following table: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Gross realized gains $ 46 $ 18 $ 52 $ 243 Gross realized losses — 1 — 155 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 June 30, 2015 and December 31, 2014 . Less than 12 Months 12 Months or More Total June 30, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: Obligations of U.S. government agencies $ 106,516 $ (460 ) $ 239,339 $ (1,844 ) $ 345,855 $ (2,304 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 254,399 (1,480 ) 133,709 (2,983 ) 388,108 (4,463 ) Private mortgage-backed securities — — 83 (2 ) 83 (2 ) Total $ 360,915 $ (1,940 ) $ 373,131 $ (4,829 ) $ 734,046 $ (6,769 ) Less than 12 Months 12 Months or More Total June 30, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 19,427 $ (165 ) $ 13,513 $ (359 ) $ 32,940 $ (524 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 85,286 (3,288 ) — — 85,286 (3,288 ) Corporate securities 31,291 (204 ) — — 31,291 (204 ) Total $ 136,004 $ (3,657 ) $ 13,513 $ (359 ) $ 149,517 $ (4,016 ) Less than 12 Months 12 Months or More Total December 31, 2014 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: Obligations of U.S. government agencies $ 135,888 $ (702 ) $ 309,283 $ (4,668 ) $ 445,171 $ (5,370 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 219,214 (887 ) 151,380 (2,737 ) 370,594 (3,624 ) Private mortgage-backed securities — — 90 (2 ) 90 (2 ) Total $ 355,102 $ (1,589 ) $ 460,753 $ (7,407 ) $ 815,855 $ (8,996 ) Less than 12 Months 12 Months or More Total December 31, 2014 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 7,979 $ (13 ) $ 20,097 $ (373 ) $ 28,076 $ (386 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 61,201 (1,758 ) — — 61,201 (1,758 ) Corporate securities 14,755 (75 ) — — 14,755 (75 ) Total $ 83,935 $ (1,846 ) $ 20,097 $ (373 ) $ 104,032 $ (2,219 ) The investment portfolio is evaluated quarterly for other-than-temporary declines in the market value of each individual investment security. The Company had 190 and 154 individual investment securities that were in an unrealized loss position as of June 30, 2015 and December 31, 2014 , respectively. Unrealized losses as of June 30, 2015 and December 31, 2014 related primarily to fluctuations in the current interest rates. The Company does not have the intent to sell any of the available-for-sale securities in the above table and it is not likely that the Company will have to sell any such securities before a recovery in cost. No impairment losses were recorded during the three and six months ended June 30, 2015 and 2014 . Maturities of investment securities at June 30, 2015 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 June 30, 2015 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Within one year $ 321,079 $ 322,976 $ 97,639 $ 98,594 After one year but within five years 1,189,454 1,192,101 273,778 276,390 After five years but within ten years 58,106 58,232 125,446 127,706 After ten years 19,314 19,434 49,827 50,633 Total $ 1,587,953 $ 1,592,743 $ 546,690 $ 553,323 As of June 30, 2015 , the Company had investment securities callable within one year with amortized costs and estimated fair values of $ 104,832 and $ 104,923 , respectively, including callable structured notes with amortized costs and estimated fair values of $ 4,996 and $ 5,004 , respectively. These investment securities are primarily classified as available-for-sale and included in the after one year but within five years category in the table above.

Loans

Loans	6 Months Ended
	Jun. 30, 2015
Receivables [Abstract]
Loans	Loans The following table presents loans by class as of the dates indicated: June 30, December 31, Real estate loans: Commercial $ 1,704,073 $ 1,639,422 Construction: Land acquisition & development 211,889 220,443 Residential 101,023 96,580 Commercial 90,316 101,246 Total construction loans 403,228 418,269 Residential 999,038 999,903 Agricultural 158,506 167,659 Total real estate loans 3,264,845 3,225,253 Consumer: Indirect consumer 589,479 552,863 Other consumer 144,919 144,141 Credit card 64,728 65,467 Total consumer loans 799,126 762,471 Commercial 819,119 740,073 Agricultural 142,629 124,859 Other, including overdrafts 2,905 3,959 Loans held for investment 5,028,624 4,856,615 Mortgage loans held for sale 75,322 40,828 Total loans $ 5,103,946 $ 4,897,443 Loans from business combinations included in the table 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 June 30, 2015 and 2014 : As of June 30, 2015 2014 Outstanding balance $ 35,555 $ — Carrying value Loans on accrual status 22,293 — Loans on non-accrual status — — Total carrying value $ 22,293 $ — The following table summarizes changes in the accretable yield for loans acquired credit impaired for the three and six ended June 30, 2015 and 2014 : Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Beginning balance $ 6,980 $ — $ 5,781 $ — Accretion income (807 ) — (1,355 ) — Reductions due to exit events — — (396 ) — Reclassifications from (to) nonaccretable differences 1,309 — 3,452 — Ending balance $ 7,482 $ — $ 7,482 $ — 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 June 30, 2015 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 5,123 $ 2,803 $ 111 $ 8,037 $ 1,669,445 $ 26,591 $ 1,704,073 Construction: Land acquisition & development 1,075 276 156 1,507 202,620 7,762 211,889 Residential 417 — — 417 100,274 332 101,023 Commercial — — — — 86,874 3,442 90,316 Total construction loans 1,492 276 156 1,924 389,768 11,536 403,228 Residential 3,563 1,524 929 6,016 990,453 2,569 999,038 Agricultural 875 261 — 1,136 150,586 6,784 158,506 Total real estate loans 11,053 4,864 1,196 17,113 3,200,252 47,480 3,264,845 Consumer: Indirect consumer 3,382 507 26 3,915 585,200 364 589,479 Other consumer 785 121 29 935 143,241 743 144,919 Credit card 415 224 391 1,030 63,684 14 64,728 Total consumer loans 4,582 852 446 5,880 792,125 1,121 799,126 Commercial 8,285 812 190 9,287 788,210 21,622 819,119 Agricultural 700 30 10 740 141,264 625 142,629 Other, including overdrafts — — 311 311 2,594 — 2,905 Loans held for investment 24,620 6,558 2,153 33,331 4,924,445 70,848 5,028,624 Mortgage loans originated for sale — — — — 75,322 — 75,322 Total loans $ 24,620 $ 6,558 $ 2,153 $ 33,331 $ 4,999,767 $ 70,848 $ 5,103,946 Total Loans 30 - 59 60 - 89 > 90 30 or More Days Days Days Days Current Non-accrual Total As of December 31, 2014 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 4,692 $ 1,609 $ 331 $ 6,632 $ 1,605,421 $ 27,369 $ 1,639,422 Construction: Land acquisition & development 839 383 — 1,222 210,969 8,252 220,443 Residential — 475 — 475 95,833 272 96,580 Commercial 100 — — 100 98,582 2,564 101,246 Total construction loans 939 858 — 1,797 405,384 11,088 418,269 Residential 6,969 645 1,762 9,376 987,735 2,792 999,903 Agricultural 1,624 236 — 1,860 158,957 6,842 167,659 Total real estate loans 14,224 3,348 2,093 19,665 3,157,497 48,091 3,225,253 Consumer: Indirect consumer 3,235 482 6 3,723 548,757 383 552,863 Other consumer 988 140 32 1,160 142,432 549 144,141 Credit card 369 284 315 968 64,484 15 65,467 Total consumer loans 4,592 906 353 5,851 755,673 947 762,471 Commercial 3,659 994 147 4,800 722,575 12,698 740,073 Agricultural 1,125 — — 1,125 123,288 446 124,859 Other, including overdrafts — — — — 3,959 — 3,959 Loans held for investment 23,600 5,248 2,593 31,441 4,762,992 62,182 4,856,615 Mortgage loans originated for sale — — — — 40,828 — 40,828 Total loans $ 23,600 $ 5,248 $ 2,593 $ 31,441 $ 4,803,820 $ 62,182 $ 4,897,443 Acquired loans that met the criteria for nonaccrual of interest prior to the acquisition were considered performing upon acquisition. If interest on non-accrual loans had been accrued, such income would have been approximately $ 875 and $ 1,061 for the three months ended June 30, 2015 and 2014 , respectively, and approximately $1,613 and $2,182 for the six months ended June 30, 2015 and 2014 respectively. The Company considers impaired loans to include all 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 June 30, 2015 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 60,786 $ 31,201 $ 17,201 $ 48,402 $ 1,810 Construction: Land acquisition & development 22,630 6,452 5,915 12,367 569 Residential 969 332 — 332 — Commercial 3,796 426 1,590 2,016 1,606 Total construction loans 27,395 7,210 7,505 14,715 2,175 Residential 5,442 2,291 1,429 3,720 127 Agricultural 9,094 6,396 2,202 8,598 712 Total real estate loans 102,717 47,098 28,337 75,435 4,824 Commercial 28,472 11,275 12,298 23,573 3,279 Agricultural 2,110 427 1,058 1,485 618 Total $ 133,299 $ 58,800 $ 41,693 $ 100,493 $ 8,721 As of December 31, 2014 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 41,603 $ 28,143 $ 11,246 $ 39,389 $ 1,608 Construction: Land acquisition & development 12,511 7,262 1,615 8,877 574 Residential 459 272 — 272 — Commercial 2,729 253 2,442 2,695 904 Total construction loans 15,699 7,787 4,057 11,844 1,478 Residential 2,959 2,452 341 2,793 143 Agricultural 8,844 6,444 2,305 8,749 732 Total real estate loans 69,105 44,826 17,949 62,775 3,961 Commercial 16,904 11,882 2,644 14,526 1,190 Agricultural 1,231 342 837 1,179 641 Total $ 87,240 $ 57,050 $ 21,430 $ 78,480 $ 5,792 The following table presents the average recorded investment in and income recognized on impaired loans for the periods indicated: Three Months Ended June 30, 2015 2014 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 39,513 $ 211 $ 57,588 $ 241 Construction: Land acquisition & development 8,664 12 13,563 11 Residential 338 — 785 — Commercial 3,492 — 1,471 2 Total construction loans 12,494 12 15,819 13 Residential 3,014 1 5,852 1 Agricultural 8,572 13 9,747 25 Total real estate loans 63,593 237 89,006 280 Commercial 21,841 112 14,162 14 Agricultural 1,004 8 742 6 Total $ 86,438 $ 357 $ 103,910 $ 300 Six Months Ended June 30, 2015 2014 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 40,652 $ 361 $ 60,870 $ 457 Construction: Land acquisition & development 8,720 22 14,554 22 Residential 302 — 1,051 — Commercial 3,133 2 918 4 Total construction loans 12,155 24 16,523 26 Residential 2,719 2 5,969 3 Agricultural 8,666 35 9,830 29 Total real estate loans 64,192 422 93,192 515 Commercial 17,874 120 14,231 28 Agricultural 857 13 538 12 Total $ 82,923 $ 555 $ 107,961 $ 555 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 $ 1,045 and $ 1,301 for the three months ended June 30, 2015 and 2014 , respectively, and approximately $2,011 and $2,412 for the six months ended June 30, 2015 and 2014 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 $ 37,363 as of June 30, 2015 , of which $ 22,236 were included in non-accrual loans and $ 15,127 were on accrual status. The Company had loans renegotiated in troubled debt restructurings of $ 44,227 as of December 31, 2014 , of which $ 23,275 were included in non-accrual loans and $ 20,952 were on accrual status. No troubled debt restructurings occurred during the three months ended June 30, 2015 . The following table presents information on the Company's troubled debt restructurings that occurred during the six months ended June 30, 2015 : Number of Notes Type of Concession Principal Balance at Restructure Date Six Months Ended June 30, 2015 Interest only period Extension of terms or maturity Interest rate adjustment Other Commercial 1 $ — $ 10 $ — $ — $ 10 Total loans restructured during period 1 $ — $ 10 $ — $ — $ 10 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 or six months ended June 30, 2015 or 2014 . 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 periods indicated. 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 June 30, 2015 Six Months Ended June 30, 2015 Number of Notes Balance Number of Notes Balance Commercial Real Estate — $ — 1 $ 1,822 At June 30, 2015 , 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 June 30, 2015 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 83,194 $ 85,323 $ 7,952 $ 176,469 Construction: Land acquisition & development 13,426 14,190 2,031 29,647 Residential 857 2,165 29 3,051 Commercial — 409 3,161 3,570 Total construction loans 14,283 16,764 5,221 36,268 Residential 8,434 9,387 1,002 18,823 Agricultural 9,826 14,838 595 25,259 Total real estate loans 115,737 126,312 14,770 256,819 Consumer: Indirect consumer 843 1,454 161 2,458 Other consumer 557 930 349 1,836 Credit card — — — — Total consumer loans 1,400 2,384 510 4,294 Commercial 34,776 24,519 15,691 74,986 Agricultural 3,794 6,684 730 11,208 Total $ 155,707 $ 159,899 $ 31,701 $ 347,307 As of December 31, 2014 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 84,533 $ 83,448 $ 15,246 $ 183,227 Construction: Land acquisition & development 11,826 15,016 2,507 29,349 Residential 2,029 2,666 — 4,695 Commercial 39 253 2,442 2,734 Total construction loans 13,894 17,935 4,949 36,778 Residential 10,473 10,848 1,121 22,442 Agricultural 10,122 12,328 612 23,062 Total real estate loans 119,022 124,559 21,928 265,509 Consumer: Indirect consumer 916 1,590 121 2,627 Other consumer 553 1,085 432 2,070 Credit card — 348 1,263 1,611 Total consumer loans 1,469 3,023 1,816 6,308 Commercial 25,766 32,433 10,273 68,472 Agricultural 7,827 3,660 837 12,324 Total $ 154,084 $ 163,675 $ 34,854 $ 352,613 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	6 Months Ended
	Jun. 30, 2015
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 June 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 53,659 $ 5,499 $ 15,196 $ 982 $ — $ 75,336 Provision charged to operating expense 461 646 224 9 — 1,340 Less loans charged-off (610 ) (837 ) (61 ) — — (1,508 ) Add back recoveries of loans previously charged-off 425 520 438 1 — 1,384 Ending balance $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 Six Months Ended June 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 (570 ) 1,771 1,217 17 — 2,435 Less loans charged-off (795 ) (2,138 ) (435 ) — — (3,368 ) Add back recoveries of loans previously charged-off 1,416 1,160 708 1 — 3,285 Ending balance $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 As of June 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 4,824 $ — $ 3,279 $ 618 $ — $ 8,721 Loans collectively evaluated for impairment 49,111 5,828 12,518 374 — 67,831 Allowance for loan losses $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 Total loans: Individually evaluated for impairment $ 75,435 $ — $ 23,573 $ 1,485 $ — $ 100,493 Collectively evaluated for impairment 3,264,732 799,126 795,546 141,144 2,905 5,003,453 Total loans $ 3,340,167 $ 799,126 $ 819,119 $ 142,629 $ 2,905 $ 5,103,946 Three Months Ended June 30, 2014 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 59,830 $ 5,377 $ 15,701 $ 463 $ — $ 81,371 Provision charged to operating expense (2,011 ) 346 (494 ) 158 — (2,001 ) Less loans charged-off (1,158 ) (934 ) (534 ) — — (2,626 ) Add back recoveries of loans previously charged-off 651 558 313 — — 1,522 Ending balance $ 57,312 $ 5,347 $ 14,986 $ 621 $ — $ 78,266 Six Months Ended June 30, 2014 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 63,923 $ 6,193 $ 14,747 $ 476 $ — $ 85,339 Provision charged to operating expense (5,386 ) (232 ) (1,566 ) 183 — (7,001 ) Less loans charged-off (2,243 ) (1,780 ) (1,330 ) (64 ) — (5,417 ) Add back recoveries of loans previously charged-off 1,018 1,166 3,135 26 — 5,345 Ending balance $ 57,312 $ 5,347 $ 14,986 $ 621 $ — $ 78,266 As of December 31, 2014 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 3,961 $ — $ 1,190 $ 641 $ — $ 5,792 Loans collectively evaluated for impairment 49,923 5,035 13,117 333 — 68,408 Allowance for loan losses $ 53,884 $ 5,035 $ 14,307 $ 974 $ — $ 74,200 Total loans: Individually evaluated for impairment $ 62,775 $ — $ 14,526 $ 1,179 $ — $ 78,480 Collectively evaluated for impairment 3,203,306 762,471 725,547 123,680 3,959 4,818,963 Total loans $ 3,266,081 $ 762,471 $ 740,073 $ 124,859 $ 3,959 $ 4,897,443 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 June 30, 2015 and December 31, 2014 , the Company's allowance for loan losses included $501 and $287 , respectively, related to acquired loans.

OREO

OREO	6 Months Ended
	Jun. 30, 2015
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 June 30, Six Months Ended June 30, 2015 2014 2015 2014 Beginning balance $ 15,134 $ 16,594 $ 13,554 $ 15,504 Additions 1,139 984 4,396 4,399 Valuation adjustments — (10 ) (106 ) (10 ) Dispositions (4,500 ) (1,143 ) (6,071 ) (3,468 ) Ending balance $ 11,773 $ 16,425 $ 11,773 $ 16,425 Foreclosed residential real estate properties of $ 3,708 were included in other real estate owned as of June 30, 2015 . Consumer mortgage loans collateralized by residential real estate property of $65 were in the process of foreclosure as of June 30, 2015 .

Long Term Debt

Long Term Debt	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Long-term Debt [Text Block]	Long-Term Debt On January 29, 2015 , the Company borrowed $ 4,960 on a 2.28% note payable maturing July 29, 2022 , with interest payable monthly and principal due at maturity. The note is collateralized by the Company's equity interest in Universal Sub CDE, LLC, a community development entity owned 99.9% by the Company.

Capital Stock

Capital Stock	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Common Stock	Capital Stock The Company had 21,720,287 shares of Class A common stock and 23,786,296 shares of Class B common stock outstanding as of June 30, 2015 . The Company had 21,928,932 shares of Class A common stock and 23,859,483 shares of Class B common stock outstanding as of December 31, 2014 . During the six months ended June 30, 2015 , the Company repurchased and retired 565,875 shares of its Class A common stock in open market transactions at an aggregate purchase price of $ 14,674 . During the six months ended June 30, 2014 , the Company repurchased and retired 325,418 shares of its Class A common stock in a privately negotiated transaction at an aggregate purchase price of $8,143 . The 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 434,125 shares of its Class A common stock. All other stock repurchases during the three and six months ended June 30, 2015 and 2014 were redemptions of vested restricted shares tendered in lieu of cash for payment of income tax withholding amounts by participants of the Company's 2006 Equity Compensation Plan. On April 3, 2015 , the Company filed a Registration Statement on Form S-8 to register an additional 2,000,000 shares of Class A common stock to be issued pursuant to the Company's 2015 Equity and Incentive Plan.

Earnings per Common Share

Earnings per Common Share	6 Months Ended
	Jun. 30, 2015
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 six month periods ended June 30, 2015 and 2014 . Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Net income $ 22,222 $ 21,077 $ 43,202 $ 42,470 Weighted average common shares outstanding for basic earnings per share computation 45,143,122 44,044,260 45,260,104 44,021,166 Dilutive effects of stock-based compensation 463,564 531,703 582,935 573,689 Weighted average common shares outstanding for diluted earnings per common share computation 45,606,686 44,575,963 45,843,039 44,594,855 Basic earnings per common share $ 0.49 $ 0.48 $ 0.95 $ 0.96 Diluted earnings per common share $ 0.49 $ 0.47 $ 0.94 $ 0.95 The Company had 166,362 and 107,651 shares of unvested restricted stock as of June 30, 2015 and 2014 , respectively, that were not included in the computation of diluted earnings per common share because performance conditions for vesting had not been met. The Company had no anti-dilutive stock options outstanding as of June 30, 2015 or June 30, 2014 .

Regulatory Capital

Regulatory Capital	6 Months Ended
	Jun. 30, 2015
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 and satisfying related mandates under the Dodd-Frank Wall Street Reform and Consumer Protection Act . The revised regulatory capital framework ("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. As a banking organization subject to the standardized approach, Basel III became effective for us on January 1, 2015. 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 phases in beginning January 1, 2016 and will be fully implemented on January 1, 2019. CET1 capital predominantly includes common shareholders’ equity, less certain deductions for goodwill, intangible assets and deferred tax assets that arise from net operating losses and tax credit carry-forwards. We have elected to permanently exclude capital in accumulated other comprehensive income related to debt and equity securities classified as available-for-sale as well as for defined benefit post-retirement plans from CET1. Certain deductions and adjustments to CET1 capital, tier 1 capital and tier 2 capital are subject to phase-in through December 31, 2017. As of June 30, 2015 and December 31, 2014 , 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 June 30, 2015 and December 31, 2014 are presented in the following tables: Actual Adequately Capitalized Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio June 30, 2015 Total risk-based capital: Consolidated $ 924,408 15.4 % $ 481,244 8.0 % $ 601,555 10.0 % FIB 857,522 14.3 479,416 8.0 599,270 10.0 Tier 1 risk-based capital: Consolidated 835,198 13.9 360,933 6.0 481,244 8.0 FIB 776,594 13.0 359,562 6.0 479,416 8.0 Common equity tier 1 risk-based capital: Consolidated 755,198 12.6 270,700 4.5 391,011 6.5 FIB 776,594 13.0 269,671 4.5 389,525 6.5 Leverage capital ratio: Consolidated 835,198 10.1 330,350 4.0 412,938 5.0 FIB 776,594 9.4 329,180 4.0 411,475 5.0 Actual Adequately Capitalized Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio December 31, 2014 Total risk-based capital: Consolidated $ 897,769 16.2 % $ 444,685 8.0 % $ 555,856 10.0 % FIB 832,907 15.1 442,468 8.0 553,085 10.0 Tier 1 risk-based capital: Consolidated 807,229 14.5 222,343 4.0 333,514 6.0 FIB 754,708 13.7 221,234 4.0 331,851 6.0 Leverage capital ratio: Consolidated 807,229 9.6 335,897 4.0 419,871 5.0 FIB 754,708 9.2 330,006 4.0 412,507 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	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings. First Interstate Bank ("the Bank"), a wholly owned banking subsidiary of the Company, was a defendant in a lender liability lawsuit , Kelly Logging Inc. v. First Interstate Bank ("the case"). The case was tried in August 2014 in the Montana Fourth Judicial District, Missoula County in Missoula, Montana ("the court"). On August, 2014 , a jury awarded damages to Kelly Logging of $ 17,047 , which included $ 287 in compensatory damages and $ 16,760 in punitive damages. On October 1, 2014 , a non-final judgment was entered in this matter in the amount of $ 17,047 plus reasonable attorney fees and interest, subject to the court's mandatory review of the jury's punitive damages award and rulings on pending post-trial motions. On April 21, 2015 , the court ruled on the post-trial motions and issued an order upholding the jury's punitive damage award. The order also awarded plaintiff attorney's fees of $ 7,500 and costs of $ 91 , for a final judgment amount of $ 24,638 plus interest. The Company believes it has meritorious grounds for appeal of the final judgment and, in the event mandatory mediation of the case scheduled for third quarter 2015 is unsuccessful, intends to appeal to the Montana Supreme Court to set aside or substantially reduce the punitive damages award and grant the Bank a new trial. In recent appellate cases, the Montana Supreme Court has reduced excessive punitive damage awards to comply with the upper limit of the federal due process guidelines, or to an amount equal to less than ten times the compensatory damages awarded, in even the most egregious cases. Although the Company believes it has meritorious defenses and appellate issues for this litigation, these proceedings are subject to many uncertainties and, given their complexity and scope, the final outcome cannot be predicted and could have a material adverse effect on the consolidated financial condition, results of operations or liquidity of the Company. During third quarter 2014, the Company accrued $ 4,000 of litigation-related expense, which takes into consideration the federal due process guidelines related to punitive damage awards and the plaintiff's attorneys fees. 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. Other Commitments. As of June 30, 2015 , the Company had commitments under construction agreements of $2,433 .

Financial Instruments with Off-

Financial Instruments with Off-Balance Sheet Risk	6 Months Ended
	Jun. 30, 2015
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 June 30, 2015 , commitments to extend credit to existing and new borrowers approximated $ 995,388 , which included $ 528,943 on unused credit card lines and $ 357,999 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 June 30, 2015 , the Company had outstanding standby letters of credit of $ 58,105 . 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.

Supplemental Disclosures to Con

Supplemental Disclosures to Consolidated Statement of Cash Flows	6 Months Ended
	Jun. 30, 2015
Supplemental Cash Flow Information [Abstract]
Supplemental Disclosures to Consolidated Statement of Cash Flows	Supplemental Disclosures to Consolidated Statement of Cash Flows The Company transferred loans of $ 4,396 and $ 4,399 to OREO during the six months ended June 30, 2015 and 2014 , respectively. The Company transferred internally originated mortgage servicing rights of $ 1,792 and $ 1,024 from loans to mortgage servicing assets during the six months ended June 30, 2015 and 2014 , respectively. The Company transferred loans of $10,619 to loans held for sale during the six months ended June 30, 2015 .

Other Comprehensive Income

Other Comprehensive Income	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Other Comprehensive Income	Other Comprehensive Income/Loss The gross amounts of each component of other comprehensive income (loss) and the related tax effects are as follows: Pre-tax Tax Expense (Benefit) Net of Tax Three Months Ended June 30, 2015 2014 2015 2014 2015 2014 Investment securities available-for sale: Change in net unrealized gains/losses $ (9,196 ) $ 2,816 $ (3,618 ) $ 1,108 $ (5,578 ) $ 1,708 Reclassification adjustment for net gains included in net income (46 ) (17 ) (18 ) (7 ) (28 ) (10 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 451 — 177 — 274 — Defined benefits post-retirement benefit plan: Change in net actuarial loss 13 35 5 14 8 21 Total other comprehensive income (loss) $ (8,778 ) $ 2,834 $ (3,454 ) $ 1,115 $ (5,324 ) $ 1,719 Pre-tax Tax Expense (Benefit) Net of Tax Six Months Ended June 30, 2015 2014 2015 2014 2015 2014 Investment securities available-for sale: Change in net unrealized gains/losses $ 1,412 $ 17,167 $ 555 $ 6,755 $ 857 $ 10,412 Reclassification adjustment for net gains included in net income (52 ) (88 ) (20 ) (35 ) (32 ) (53 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 902 — 355 — 547 — Defined benefits post-retirement benefit plan: Change in net actuarial loss 28 70 11 28 17 42 Total other comprehensive income $ 2,290 $ 17,149 $ 901 $ 6,748 $ 1,389 $ 10,401 The components of accumulated other comprehensive loss, net of income tax benefits, are as follows: June 30, December 31, Net unrealized loss on investment securities available-for-sale $ (749 ) $ (2,121 ) Net actuarial loss on defined benefit post-retirement benefit plans (396 ) (413 ) Net accumulated other comprehensive loss $ (1,145 ) $ (2,534 )

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements 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 June 30, 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: Obligations of U.S. government agencies $ 621,020 $ — $ 621,020 $ — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 971,435 — 971,435 — Private mortgage-backed securities 288 — 288 — Fair Value Measurements at Reporting Date Using As of December 31, 2014 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: Obligations of U.S. government agencies $ 720,933 $ — $ 720,933 $ — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 990,666 — 990,666 — Private mortgage-backed securities 325 — 325 — There were no changes in valuation methodologies or transfers between levels of the fair value hierarchy during the six months ended June 30, 2015 or 2014 . 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. The Company obtains fair value measurements for investment securities from an independent pricing service. The 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. The Company has documented and evaluated the pricing methodologies used by the vendors and maintains internal processes that regularly test valuations. These internal processes include obtaining and reviewing available reports on internal controls, evaluating the prices for reasonableness given market changes, obtaining and evaluating the inputs used in the model for a sample of securities, investigating anomalies and confirming determinations through discussions with the vendor. For investment securities, if needed, a broker may be utilized to determine the reported fair value. 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 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. 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 June 30, 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 $ 50,131 $ — $ — $ 50,131 Other real estate owned 5,623 — — 5,623 Long-lived assets to be disposed of by sale 1,083 — — 1,083 Fair Value Measurements at Reporting Date Using As of December 31, 2014 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Impaired loans $ 30,494 $ — $ — $ 30,494 Other real estate owned 4,554 — — 4,554 Long-lived assets to be disposed of by sale 1,083 — — 1,083 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 June 30, 2015 , certain impaired loans with a carrying value of $ 70,827 were reduced by specific valuation allowance allocations of $ 8,721 and partial loan charge-offs of $ 11,975 resulting in a reported fair value of $ 50,131 . As of December 31, 2014 , certain impaired loans with a carrying value of $ 45,046 were reduced by specific valuation allowance allocations of $ 5,792 and partial loan charge-offs of $ 8,760 resulting in a reported fair value of $ 30,494 . 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 $106 and $10 during the six months ended June 30, 2015 and 2014 , respectively, were based on management's estimate of the current fair value of the 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 June 30, 2015 and December 31, 2014 , the Company had long-lived assets to be disposed of by sale with carrying values aggregating $1,785 that were reduced by write-downs of $702 resulting in an aggregate fair value of $1,083 . In addition, mortgage loans held for sale are required to be measured at the lower of cost or fair value. The fair value of mortgage loans held for sale is based upon binding contracts or quotes or bids from third party investors. As of June 30, 2015 and December 31, 2014 , all mortgage loans held for sale were recorded at cost. 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: As of June 30, 2015 Fair Value Valuation Technique Unobservable Inputs Range (Weighted Average) Impaired loans $ 50,131 Appraisal Appraisal adjustment 0% - 51% (19%) Other real estate owned 5,623 Appraisal Appraisal adjustment 0% - 50% (15%) Long-lived assets to be disposed of by sale 1,083 Appraisal Appraisal adjustment 0% - 9% (5%) As of December 31, 2014 Fair Value Valuation Technique Unobservable Inputs Range (Weighted Average) Impaired loans $ 30,494 Appraisal Appraisal adjustment 0% - 51% (19%) Other real estate owned 4,554 Appraisal Appraisal adjustment 0% - 50% (15%) Long-lived assets to be disposed of by sale 1,083 Appraisal Appraisal adjustment 0% - 9% (5%) 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 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 June 30, 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 $ 506,434 $ 506,434 $ 506,434 $ — $ — Investment securities available-for-sale 1,592,743 1,592,743 — 1,592,743 — Investment securities held-to-maturity 546,690 553,323 — 553,323 — Accrued interest receivable 29,008 29,008 — 29,008 — Mortgage servicing rights, net 14,654 28,320 — 28,320 — Net loans 5,027,394 5,000,935 — 4,950,804 50,131 Total financial assets $ 7,716,923 $ 7,710,763 $ 506,434 $ 7,154,198 $ 50,131 Financial liabilities: Total deposits, excluding time deposits $ 5,655,166 $ 5,655,166 $ 5,655,166 $ — $ — Time deposits 1,149,235 1,153,809 — 1,153,809 — Securities sold under repurchase agreements 469,145 469,145 — 469,145 — Other borrowed funds 3 3 — 3 — Accrued interest payable 5,366 5,366 — 5,366 — Long-term debt 43,068 41,584 — 41,584 — Subordinated debentures held by subsidiary trusts 82,477 76,393 — 76,393 — Total financial liabilities $ 7,404,460 $ 7,401,466 $ 5,655,166 $ 1,746,300 $ — Fair Value Measurements at Reporting Date Using As of December 31, 2014 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 $ 798,670 $ 798,670 $ 798,670 $ — $ — Investment securities available-for-sale 1,711,924 1,711,924 — 1,711,924 — Investment securities held-to-maturity 575,186 584,533 — 584,533 — Accrued interest receivable 27,063 27,063 — 27,063 — Mortgage servicing rights, net 14,038 21,434 — 21,434 — Net loans 4,823,243 4,800,725 — 4,770,231 30,494 Total financial assets $ 7,950,124 $ 7,944,349 $ 798,670 $ 7,115,185 $ 30,494 Financial liabilities: Total deposits, excluding time deposits $ 5,767,992 $ 5,767,992 $ 5,767,992 $ — $ — Time deposits 1,238,220 1,244,324 — 1,244,324 — Securities sold under repurchase agreements 502,250 502,250 — 502,250 — Other borrowed funds 9 9 — 9 — Accrued interest payable 5,833 5,833 — 5,833 — Long-term debt 38,067 37,781 — 37,781 — Subordinated debentures held by subsidiary trusts 82,477 75,734 — 75,734 — Total financial liabilities $ 7,634,848 $ 7,633,923 $ 5,767,992 $ 1,865,931 $ —

Recent Authoritative Accounting

Recent Authoritative Accounting Guidance	6 Months Ended
	Jun. 30, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Authoritative Accounting Guidance	Recent Authoritative Accounting Guidance ASU 2014-04 “Receivables-Troubled Debt Restructurings by Creditors (Subtopic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure.” The amendments in ASU 2014-04 clarify that an in-substance repossession or foreclosures occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either (i) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or (ii) the borrower conveying all interest in the residential real estate property to the creditor to satisfy the loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. The amendments in ASU 2014-04 also require interim and annual disclosure of both (i) the amount of foreclosed residential real estate property held by the creditor and (ii) the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure. The Company adopted the amendments in ASU 2014-04 effective January 1, 2015 using a prospective transition method. Adoption of the amendments in ASU 2014-04 did not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2014-09 "Revenue from Contracts with Customers." The amendments in 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. The amendments in ASU 2014-09 are effective for the Company for fiscal years beginning after December 15, 2016, including interim periods within that reporting period, and may be adopted retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initial adoption recognized at the date of initial application. The Company is currently evaluating the new guidance to determine the impact it will have on its consolidated financial statements, results of operations or liquidity. ASU 2014-11 "Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures." The amendments in ASU 2014-11 expand secured borrowing treatment for certain repurchase agreements. Under the amendments in ASU 2014-11, repurchase-to-maturity transactions and repurchase agreements executed as repurchase financing transactions are required to be accounted for as secured borrowings. ASU 2014-11 requires additional disclosures about certain transactions accounted for as a sale in which the transferor retains substantially all of the exposure to the economic return on the transferred financial assets through an agreement with the same counterparty. ASU 2014-11 also requires disclosure of the types of collateral pledged and liabilities associated with an entity's repurchase agreements, securities lending transactions and repurchase-to-maturity transactions accounted for as secured borrowings. The Company adopted the amendments in ASU 2014-11 are effective January 1, 2015. The adoption did not have a material impact on the Company’s 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 amendments in ASU 2014-12 are effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. The amendments in ASU 2014-12 may be applied prospectively to all awards granted or modified after the effective date or retrospectively to all awards with performance targets that are outstanding as of the beginning of the earliest annual period presented in the financial statements and to all new or modified awards thereafter. The amendments in ASU 2014-12 will not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity. ASU 2014-14 "Classification of Certain Government-Guaranteed Mortgage Loans upon Foreclosure." ASU 2014-14 updates ASC Subtopic 310-40, Receivables-Troubled Debt Restructurings by Creditors, to require that a mortgage loan be derecognized and that a separate other receivable be recognized upon foreclosure if (i) the loan has a government guarantee that is not separable from the loan before foreclosure; (ii) at the time of foreclosure, the creditor has the intent to convey the real estate property to the guarantor and make a claim on the guarantee, and the creditor has the ability to recover under that claim; and, (iii) any amount of the claim that is determined on the basis of the fair value of the real estate is fixed at the time of foreclosure. ASU 2014-14 provides that, upon foreclosure, the separate other receivable should be measured based on the amount of the loan balance (principal and interest) expected to be recovered from the guarantor. The Company adopted the amendments in ASU 2014-14 effective January 1, 2015, using a prospective transition method. Adoption of the amendments in ASU 2014-12 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 amendments in ASU 2014-16 are effective for the Company for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. The effects of initially adopting the amendments in ASU 2014-16 should be applied on a modified retrospective basis to existing hybrid financial instruments issued in the form of a share as of the beginning of the fiscal year for which the amendments are effective. Retrospective application is permitted to all relevant prior periods. The amendments in ASU 2014-16 will 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 amendments in ASU 2015-02 are effective for public entities for fiscal years, and interim periods within those years, beginning after December 15, 2015, with early adoption permitted. The amendments in ASU 2015-02, which may be adopted using a retrospective or modified retrospective approach, will 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 amendments in ASU 2015-03 are effective for public entities for fiscal years, and interim periods within those years, beginning after December 15, 2015, and should be applied on a retrospective basis. The amendments in ASU 2015-03 will 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 (i) 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 guidance in ASU 2015-05 does not change generally accepted accounting principles for a customer's accounting for service contracts. The amendments in ASU 2015-05 are effective for public entities for annual periods, including interim periods within those annual periods, beginning after December 15, 2015, with early adoption permitted. The amendments in ASU 2015-05, which may be adopted retrospectively or prospectively to all arrangements entered into or materially modified after the effective date. Adoption of the amendments in ASU 2015-05 will 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 amendments in ASU 2015-10 that require transition guidance are effective for all entities for fiscal years, and interim periods within those years, beginning after December 15, 2015, with early adoption permitted. All other amendments in ASU 2015-10 became effective in June 2015. The amendments in ASU 2015-03 will not have a material impact on the Company’s consolidated financial statements, results of operations or liquidity.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2015
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 Securities and Exchange Commission. On July 23, 2015 , the Company declared a quarterly dividend to common shareholders of $ 0.20 per share, to be paid on August 14, 2015 to shareholders of record as of August 3, 2015 . On July 24, 2015 , the Company completed the acquisition of Absarokee, parent company of United Bank, and the subsequent merger of United Bank with and into FIB. For additional information regarding the acquisition and subsequent bank merger, see "Note 2 - Acquisitions." No other events requiring recognition or disclosure were identified.

Investment Securities (Tables)

Investment Securities (Tables)	6 Months Ended
	Jun. 30, 2015
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: June 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: Obligations of U.S. government agencies $ 622,237 $ 1,087 $ (2,304 ) $ 621,020 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 965,430 10,468 (4,463 ) 971,435 Private mortgage-backed securities 286 4 (2 ) 288 Total $ 1,587,953 $ 11,559 $ (6,769 ) $ 1,592,743 June 30, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 181,642 $ 4,644 $ (524 ) $ 185,762 Corporate securities 50,310 59 (204 ) 50,165 U.S agency residential mortgage-backed securities & collateralized mortgage obligations 314,326 5,945 (3,288 ) 316,983 Other investments 412 1 — 413 Total $ 546,690 $ 10,649 $ (4,016 ) $ 553,323 December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Available-for-Sale: Obligations of U.S. government agencies $ 725,408 $ 895 $ (5,370 ) $ 720,933 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 982,764 11,526 (3,624 ) 990,666 Private mortgage-backed securities 322 5 (2 ) 325 Total $ 1,708,494 $ 12,426 $ (8,996 ) $ 1,711,924 December 31, 2014 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Held-to-Maturity: State, county and municipal securities $ 188,941 $ 5,949 $ (386 ) $ 194,504 Corporate securities 32,565 54 (75 ) 32,544 U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 353,176 5,563 (1,758 ) 356,981 Other Investments 504 — — 504 Total $ 575,186 $ 11,566 $ (2,219 ) $ 584,533
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 June 30, Six Months Ended June 30, 2015 2014 2015 2014 Gross realized gains $ 46 $ 18 $ 52 $ 243 Gross realized losses — 1 — 155
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 June 30, 2015 and December 31, 2014 . Less than 12 Months 12 Months or More Total June 30, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: Obligations of U.S. government agencies $ 106,516 $ (460 ) $ 239,339 $ (1,844 ) $ 345,855 $ (2,304 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 254,399 (1,480 ) 133,709 (2,983 ) 388,108 (4,463 ) Private mortgage-backed securities — — 83 (2 ) 83 (2 ) Total $ 360,915 $ (1,940 ) $ 373,131 $ (4,829 ) $ 734,046 $ (6,769 ) Less than 12 Months 12 Months or More Total June 30, 2015 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 19,427 $ (165 ) $ 13,513 $ (359 ) $ 32,940 $ (524 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 85,286 (3,288 ) — — 85,286 (3,288 ) Corporate securities 31,291 (204 ) — — 31,291 (204 ) Total $ 136,004 $ (3,657 ) $ 13,513 $ (359 ) $ 149,517 $ (4,016 ) Less than 12 Months 12 Months or More Total December 31, 2014 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Available-for-Sale: Obligations of U.S. government agencies $ 135,888 $ (702 ) $ 309,283 $ (4,668 ) $ 445,171 $ (5,370 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 219,214 (887 ) 151,380 (2,737 ) 370,594 (3,624 ) Private mortgage-backed securities — — 90 (2 ) 90 (2 ) Total $ 355,102 $ (1,589 ) $ 460,753 $ (7,407 ) $ 815,855 $ (8,996 ) Less than 12 Months 12 Months or More Total December 31, 2014 Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Held-to-Maturity: State, county and municipal securities $ 7,979 $ (13 ) $ 20,097 $ (373 ) $ 28,076 $ (386 ) U.S. agency residential mortgage-backed securities & collateralized mortgage obligations 61,201 (1,758 ) — — 61,201 (1,758 ) Corporate securities 14,755 (75 ) — — 14,755 (75 ) Total $ 83,935 $ (1,846 ) $ 20,097 $ (373 ) $ 104,032 $ (2,219 )
Maturities of Investment Securities	Maturities of investment securities at June 30, 2015 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 June 30, 2015 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Within one year $ 321,079 $ 322,976 $ 97,639 $ 98,594 After one year but within five years 1,189,454 1,192,101 273,778 276,390 After five years but within ten years 58,106 58,232 125,446 127,706 After ten years 19,314 19,434 49,827 50,633 Total $ 1,587,953 $ 1,592,743 $ 546,690 $ 553,323

Loans (Tables)

Loans (Tables)	6 Months Ended
	Jun. 30, 2015
Receivables [Abstract]
Schedule of Loans by Class	June 30, December 31, Real estate loans: Commercial $ 1,704,073 $ 1,639,422 Construction: Land acquisition & development 211,889 220,443 Residential 101,023 96,580 Commercial 90,316 101,246 Total construction loans 403,228 418,269 Residential 999,038 999,903 Agricultural 158,506 167,659 Total real estate loans 3,264,845 3,225,253 Consumer: Indirect consumer 589,479 552,863 Other consumer 144,919 144,141 Credit card 64,728 65,467 Total consumer loans 799,126 762,471 Commercial 819,119 740,073 Agricultural 142,629 124,859 Other, including overdrafts 2,905 3,959 Loans held for investment 5,028,624 4,856,615 Mortgage loans held for sale 75,322 40,828 Total loans $ 5,103,946 $ 4,897,443
Schedule of acquired loans with credit impairment	The following table displays the outstanding unpaid principal balance, accrued interest receivable and accrual status of loans acquired with credit impairment as of June 30, 2015 and 2014 : As of June 30, 2015 2014 Outstanding balance $ 35,555 $ — Carrying value Loans on accrual status 22,293 — Loans on non-accrual status — — Total carrying value $ 22,293 $ — The following table summarizes changes in the accretable yield for loans acquired credit impaired for the three and six ended June 30, 2015 and 2014 : Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Beginning balance $ 6,980 $ — $ 5,781 $ — Accretion income (807 ) — (1,355 ) — Reductions due to exit events — — (396 ) — Reclassifications from (to) nonaccretable differences 1,309 — 3,452 — Ending balance $ 7,482 $ — $ 7,482 $ —
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 June 30, 2015 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 5,123 $ 2,803 $ 111 $ 8,037 $ 1,669,445 $ 26,591 $ 1,704,073 Construction: Land acquisition & development 1,075 276 156 1,507 202,620 7,762 211,889 Residential 417 — — 417 100,274 332 101,023 Commercial — — — — 86,874 3,442 90,316 Total construction loans 1,492 276 156 1,924 389,768 11,536 403,228 Residential 3,563 1,524 929 6,016 990,453 2,569 999,038 Agricultural 875 261 — 1,136 150,586 6,784 158,506 Total real estate loans 11,053 4,864 1,196 17,113 3,200,252 47,480 3,264,845 Consumer: Indirect consumer 3,382 507 26 3,915 585,200 364 589,479 Other consumer 785 121 29 935 143,241 743 144,919 Credit card 415 224 391 1,030 63,684 14 64,728 Total consumer loans 4,582 852 446 5,880 792,125 1,121 799,126 Commercial 8,285 812 190 9,287 788,210 21,622 819,119 Agricultural 700 30 10 740 141,264 625 142,629 Other, including overdrafts — — 311 311 2,594 — 2,905 Loans held for investment 24,620 6,558 2,153 33,331 4,924,445 70,848 5,028,624 Mortgage loans originated for sale — — — — 75,322 — 75,322 Total loans $ 24,620 $ 6,558 $ 2,153 $ 33,331 $ 4,999,767 $ 70,848 $ 5,103,946 Total Loans 30 - 59 60 - 89 > 90 30 or More Days Days Days Days Current Non-accrual Total As of December 31, 2014 Past Due Past Due Past Due Past Due Loans Loans Loans Real estate Commercial $ 4,692 $ 1,609 $ 331 $ 6,632 $ 1,605,421 $ 27,369 $ 1,639,422 Construction: Land acquisition & development 839 383 — 1,222 210,969 8,252 220,443 Residential — 475 — 475 95,833 272 96,580 Commercial 100 — — 100 98,582 2,564 101,246 Total construction loans 939 858 — 1,797 405,384 11,088 418,269 Residential 6,969 645 1,762 9,376 987,735 2,792 999,903 Agricultural 1,624 236 — 1,860 158,957 6,842 167,659 Total real estate loans 14,224 3,348 2,093 19,665 3,157,497 48,091 3,225,253 Consumer: Indirect consumer 3,235 482 6 3,723 548,757 383 552,863 Other consumer 988 140 32 1,160 142,432 549 144,141 Credit card 369 284 315 968 64,484 15 65,467 Total consumer loans 4,592 906 353 5,851 755,673 947 762,471 Commercial 3,659 994 147 4,800 722,575 12,698 740,073 Agricultural 1,125 — — 1,125 123,288 446 124,859 Other, including overdrafts — — — — 3,959 — 3,959 Loans held for investment 23,600 5,248 2,593 31,441 4,762,992 62,182 4,856,615 Mortgage loans originated for sale — — — — 40,828 — 40,828 Total loans $ 23,600 $ 5,248 $ 2,593 $ 31,441 $ 4,803,820 $ 62,182 $ 4,897,443
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 June 30, 2015 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 60,786 $ 31,201 $ 17,201 $ 48,402 $ 1,810 Construction: Land acquisition & development 22,630 6,452 5,915 12,367 569 Residential 969 332 — 332 — Commercial 3,796 426 1,590 2,016 1,606 Total construction loans 27,395 7,210 7,505 14,715 2,175 Residential 5,442 2,291 1,429 3,720 127 Agricultural 9,094 6,396 2,202 8,598 712 Total real estate loans 102,717 47,098 28,337 75,435 4,824 Commercial 28,472 11,275 12,298 23,573 3,279 Agricultural 2,110 427 1,058 1,485 618 Total $ 133,299 $ 58,800 $ 41,693 $ 100,493 $ 8,721 As of December 31, 2014 Unpaid Total Principal Balance Recorded Investment With No Allowance Recorded Investment With Allowance Total Recorded Investment Related Allowance Real estate: Commercial $ 41,603 $ 28,143 $ 11,246 $ 39,389 $ 1,608 Construction: Land acquisition & development 12,511 7,262 1,615 8,877 574 Residential 459 272 — 272 — Commercial 2,729 253 2,442 2,695 904 Total construction loans 15,699 7,787 4,057 11,844 1,478 Residential 2,959 2,452 341 2,793 143 Agricultural 8,844 6,444 2,305 8,749 732 Total real estate loans 69,105 44,826 17,949 62,775 3,961 Commercial 16,904 11,882 2,644 14,526 1,190 Agricultural 1,231 342 837 1,179 641 Total $ 87,240 $ 57,050 $ 21,430 $ 78,480 $ 5,792 The following table presents the average recorded investment in and income recognized on impaired loans for the periods indicated: Three Months Ended June 30, 2015 2014 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 39,513 $ 211 $ 57,588 $ 241 Construction: Land acquisition & development 8,664 12 13,563 11 Residential 338 — 785 — Commercial 3,492 — 1,471 2 Total construction loans 12,494 12 15,819 13 Residential 3,014 1 5,852 1 Agricultural 8,572 13 9,747 25 Total real estate loans 63,593 237 89,006 280 Commercial 21,841 112 14,162 14 Agricultural 1,004 8 742 6 Total $ 86,438 $ 357 $ 103,910 $ 300 Six Months Ended June 30, 2015 2014 Average Recorded Investment Income Recognized Average Recorded Investment Income Recognized Real estate: Commercial $ 40,652 $ 361 $ 60,870 $ 457 Construction: Land acquisition & development 8,720 22 14,554 22 Residential 302 — 1,051 — Commercial 3,133 2 918 4 Total construction loans 12,155 24 16,523 26 Residential 2,719 2 5,969 3 Agricultural 8,666 35 9,830 29 Total real estate loans 64,192 422 93,192 515 Commercial 17,874 120 14,231 28 Agricultural 857 13 538 12 Total $ 82,923 $ 555 $ 107,961 $ 555
Schedule of Loans Renegotiated in Troubled Debt Restructurings	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 June 30, 2015 Six Months Ended June 30, 2015 Number of Notes Balance Number of Notes Balance Commercial Real Estate — $ — 1 $ 1,822 The following table presents information on the Company's troubled debt restructurings that occurred during the six months ended June 30, 2015 : Number of Notes Type of Concession Principal Balance at Restructure Date Six Months Ended June 30, 2015 Interest only period Extension of terms or maturity Interest rate adjustment Other Commercial 1 $ — $ 10 $ — $ — $ 10 Total loans restructured during period 1 $ — $ 10 $ — $ — $ 10
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 June 30, 2015 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 83,194 $ 85,323 $ 7,952 $ 176,469 Construction: Land acquisition & development 13,426 14,190 2,031 29,647 Residential 857 2,165 29 3,051 Commercial — 409 3,161 3,570 Total construction loans 14,283 16,764 5,221 36,268 Residential 8,434 9,387 1,002 18,823 Agricultural 9,826 14,838 595 25,259 Total real estate loans 115,737 126,312 14,770 256,819 Consumer: Indirect consumer 843 1,454 161 2,458 Other consumer 557 930 349 1,836 Credit card — — — — Total consumer loans 1,400 2,384 510 4,294 Commercial 34,776 24,519 15,691 74,986 Agricultural 3,794 6,684 730 11,208 Total $ 155,707 $ 159,899 $ 31,701 $ 347,307 As of December 31, 2014 Other Assets Especially Mentioned Substandard Doubtful Total Criticized Loans Real estate: Commercial $ 84,533 $ 83,448 $ 15,246 $ 183,227 Construction: Land acquisition & development 11,826 15,016 2,507 29,349 Residential 2,029 2,666 — 4,695 Commercial 39 253 2,442 2,734 Total construction loans 13,894 17,935 4,949 36,778 Residential 10,473 10,848 1,121 22,442 Agricultural 10,122 12,328 612 23,062 Total real estate loans 119,022 124,559 21,928 265,509 Consumer: Indirect consumer 916 1,590 121 2,627 Other consumer 553 1,085 432 2,070 Credit card — 348 1,263 1,611 Total consumer loans 1,469 3,023 1,816 6,308 Commercial 25,766 32,433 10,273 68,472 Agricultural 7,827 3,660 837 12,324 Total $ 154,084 $ 163,675 $ 34,854 $ 352,613

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	6 Months Ended
	Jun. 30, 2015
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 June 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 53,659 $ 5,499 $ 15,196 $ 982 $ — $ 75,336 Provision charged to operating expense 461 646 224 9 — 1,340 Less loans charged-off (610 ) (837 ) (61 ) — — (1,508 ) Add back recoveries of loans previously charged-off 425 520 438 1 — 1,384 Ending balance $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 Six Months Ended June 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 (570 ) 1,771 1,217 17 — 2,435 Less loans charged-off (795 ) (2,138 ) (435 ) — — (3,368 ) Add back recoveries of loans previously charged-off 1,416 1,160 708 1 — 3,285 Ending balance $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 As of June 30, 2015 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 4,824 $ — $ 3,279 $ 618 $ — $ 8,721 Loans collectively evaluated for impairment 49,111 5,828 12,518 374 — 67,831 Allowance for loan losses $ 53,935 $ 5,828 $ 15,797 $ 992 $ — $ 76,552 Total loans: Individually evaluated for impairment $ 75,435 $ — $ 23,573 $ 1,485 $ — $ 100,493 Collectively evaluated for impairment 3,264,732 799,126 795,546 141,144 2,905 5,003,453 Total loans $ 3,340,167 $ 799,126 $ 819,119 $ 142,629 $ 2,905 $ 5,103,946 Three Months Ended June 30, 2014 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 59,830 $ 5,377 $ 15,701 $ 463 $ — $ 81,371 Provision charged to operating expense (2,011 ) 346 (494 ) 158 — (2,001 ) Less loans charged-off (1,158 ) (934 ) (534 ) — — (2,626 ) Add back recoveries of loans previously charged-off 651 558 313 — — 1,522 Ending balance $ 57,312 $ 5,347 $ 14,986 $ 621 $ — $ 78,266 Six Months Ended June 30, 2014 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Beginning balance $ 63,923 $ 6,193 $ 14,747 $ 476 $ — $ 85,339 Provision charged to operating expense (5,386 ) (232 ) (1,566 ) 183 — (7,001 ) Less loans charged-off (2,243 ) (1,780 ) (1,330 ) (64 ) — (5,417 ) Add back recoveries of loans previously charged-off 1,018 1,166 3,135 26 — 5,345 Ending balance $ 57,312 $ 5,347 $ 14,986 $ 621 $ — $ 78,266 As of December 31, 2014 Real Estate Consumer Commercial Agriculture Other Total Allowance for loan losses: Loans individually evaluated for impairment $ 3,961 $ — $ 1,190 $ 641 $ — $ 5,792 Loans collectively evaluated for impairment 49,923 5,035 13,117 333 — 68,408 Allowance for loan losses $ 53,884 $ 5,035 $ 14,307 $ 974 $ — $ 74,200 Total loans: Individually evaluated for impairment $ 62,775 $ — $ 14,526 $ 1,179 $ — $ 78,480 Collectively evaluated for impairment 3,203,306 762,471 725,547 123,680 3,959 4,818,963 Total loans $ 3,266,081 $ 762,471 $ 740,073 $ 124,859 $ 3,959 $ 4,897,443

OREO (Tables)

OREO (Tables)	6 Months Ended
	Jun. 30, 2015
Repossessed Assets [Abstract]
Other Real Estate Owned Roll Forward	Information with respect to the Company's other real estate owned follows: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Beginning balance $ 15,134 $ 16,594 $ 13,554 $ 15,504 Additions 1,139 984 4,396 4,399 Valuation adjustments — (10 ) (106 ) (10 ) Dispositions (4,500 ) (1,143 ) (6,071 ) (3,468 ) Ending balance $ 11,773 $ 16,425 $ 11,773 $ 16,425 Foreclosed residential real estate properties of $ 3,708 were included in other real estate owned as of June 30, 2015 . Consumer mortgage loans collateralized by residential real estate property of $65 were in the process of foreclosure as of June 30, 2015 .

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
	Jun. 30, 2015
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 six month periods ended June 30, 2015 and 2014 . Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Net income $ 22,222 $ 21,077 $ 43,202 $ 42,470 Weighted average common shares outstanding for basic earnings per share computation 45,143,122 44,044,260 45,260,104 44,021,166 Dilutive effects of stock-based compensation 463,564 531,703 582,935 573,689 Weighted average common shares outstanding for diluted earnings per common share computation 45,606,686 44,575,963 45,843,039 44,594,855 Basic earnings per common share $ 0.49 $ 0.48 $ 0.95 $ 0.96 Diluted earnings per common share $ 0.49 $ 0.47 $ 0.94 $ 0.95

Regulatory Capital (Tables)

Regulatory Capital (Tables)	6 Months Ended
	Jun. 30, 2015
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 June 30, 2015 and December 31, 2014 are presented in the following tables: Actual Adequately Capitalized Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio June 30, 2015 Total risk-based capital: Consolidated $ 924,408 15.4 % $ 481,244 8.0 % $ 601,555 10.0 % FIB 857,522 14.3 479,416 8.0 599,270 10.0 Tier 1 risk-based capital: Consolidated 835,198 13.9 360,933 6.0 481,244 8.0 FIB 776,594 13.0 359,562 6.0 479,416 8.0 Common equity tier 1 risk-based capital: Consolidated 755,198 12.6 270,700 4.5 391,011 6.5 FIB 776,594 13.0 269,671 4.5 389,525 6.5 Leverage capital ratio: Consolidated 835,198 10.1 330,350 4.0 412,938 5.0 FIB 776,594 9.4 329,180 4.0 411,475 5.0 Actual Adequately Capitalized Well Capitalized (1) Amount Ratio Amount Ratio Amount Ratio December 31, 2014 Total risk-based capital: Consolidated $ 897,769 16.2 % $ 444,685 8.0 % $ 555,856 10.0 % FIB 832,907 15.1 442,468 8.0 553,085 10.0 Tier 1 risk-based capital: Consolidated 807,229 14.5 222,343 4.0 333,514 6.0 FIB 754,708 13.7 221,234 4.0 331,851 6.0 Leverage capital ratio: Consolidated 807,229 9.6 335,897 4.0 419,871 5.0 FIB 754,708 9.2 330,006 4.0 412,507 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)	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Schedule of Comprehensive Income (Loss)	Other Comprehensive Income/Loss The gross amounts of each component of other comprehensive income (loss) and the related tax effects are as follows: Pre-tax Tax Expense (Benefit) Net of Tax Three Months Ended June 30, 2015 2014 2015 2014 2015 2014 Investment securities available-for sale: Change in net unrealized gains/losses $ (9,196 ) $ 2,816 $ (3,618 ) $ 1,108 $ (5,578 ) $ 1,708 Reclassification adjustment for net gains included in net income (46 ) (17 ) (18 ) (7 ) (28 ) (10 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 451 — 177 — 274 — Defined benefits post-retirement benefit plan: Change in net actuarial loss 13 35 5 14 8 21 Total other comprehensive income (loss) $ (8,778 ) $ 2,834 $ (3,454 ) $ 1,115 $ (5,324 ) $ 1,719 Pre-tax Tax Expense (Benefit) Net of Tax Six Months Ended June 30, 2015 2014 2015 2014 2015 2014 Investment securities available-for sale: Change in net unrealized gains/losses $ 1,412 $ 17,167 $ 555 $ 6,755 $ 857 $ 10,412 Reclassification adjustment for net gains included in net income (52 ) (88 ) (20 ) (35 ) (32 ) (53 ) Change in unamortized loss on available- for-sale securities transferred into held-to- maturity 902 — 355 — 547 — Defined benefits post-retirement benefit plan: Change in net actuarial loss 28 70 11 28 17 42 Total other comprehensive income $ 2,290 $ 17,149 $ 901 $ 6,748 $ 1,389 $ 10,401
Schedule of Accumulated Other Comprehensive Income (Loss)	The components of accumulated other comprehensive loss, net of income tax benefits, are as follows: June 30, December 31, Net unrealized loss on investment securities available-for-sale $ (749 ) $ (2,121 ) Net actuarial loss on defined benefit post-retirement benefit plans (396 ) (413 ) Net accumulated other comprehensive loss $ (1,145 ) $ (2,534 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2015
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 June 30, 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: Obligations of U.S. government agencies $ 621,020 $ — $ 621,020 $ — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 971,435 — 971,435 — Private mortgage-backed securities 288 — 288 — Fair Value Measurements at Reporting Date Using As of December 31, 2014 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: Obligations of U.S. government agencies $ 720,933 $ — $ 720,933 $ — U.S. agencies mortgage-backed securities & collateralized mortgage obligations 990,666 — 990,666 — Private mortgage-backed securities 325 — 325 —
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 June 30, 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 $ 50,131 $ — $ — $ 50,131 Other real estate owned 5,623 — — 5,623 Long-lived assets to be disposed of by sale 1,083 — — 1,083 Fair Value Measurements at Reporting Date Using As of December 31, 2014 Balance Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Impaired loans $ 30,494 $ — $ — $ 30,494 Other real estate owned 4,554 — — 4,554 Long-lived assets to be disposed of by sale 1,083 — — 1,083
Fair Value Inputs, Assets, Quantitative Information	As of June 30, 2015 Fair Value Valuation Technique Unobservable Inputs Range (Weighted Average) Impaired loans $ 50,131 Appraisal Appraisal adjustment 0% - 51% (19%) Other real estate owned 5,623 Appraisal Appraisal adjustment 0% - 50% (15%) Long-lived assets to be disposed of by sale 1,083 Appraisal Appraisal adjustment 0% - 9% (5%) As of December 31, 2014 Fair Value Valuation Technique Unobservable Inputs Range (Weighted Average) Impaired loans $ 30,494 Appraisal Appraisal adjustment 0% - 51% (19%) Other real estate owned 4,554 Appraisal Appraisal adjustment 0% - 50% (15%) Long-lived assets to be disposed of by sale 1,083 Appraisal Appraisal adjustment 0% - 9% (5%)
Fair Value, by Balance Sheet Grouping	Fair Value Measurements at Reporting Date Using As of June 30, 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 $ 506,434 $ 506,434 $ 506,434 $ — $ — Investment securities available-for-sale 1,592,743 1,592,743 — 1,592,743 — Investment securities held-to-maturity 546,690 553,323 — 553,323 — Accrued interest receivable 29,008 29,008 — 29,008 — Mortgage servicing rights, net 14,654 28,320 — 28,320 — Net loans 5,027,394 5,000,935 — 4,950,804 50,131 Total financial assets $ 7,716,923 $ 7,710,763 $ 506,434 $ 7,154,198 $ 50,131 Financial liabilities: Total deposits, excluding time deposits $ 5,655,166 $ 5,655,166 $ 5,655,166 $ — $ — Time deposits 1,149,235 1,153,809 — 1,153,809 — Securities sold under repurchase agreements 469,145 469,145 — 469,145 — Other borrowed funds 3 3 — 3 — Accrued interest payable 5,366 5,366 — 5,366 — Long-term debt 43,068 41,584 — 41,584 — Subordinated debentures held by subsidiary trusts 82,477 76,393 — 76,393 — Total financial liabilities $ 7,404,460 $ 7,401,466 $ 5,655,166 $ 1,746,300 $ — Fair Value Measurements at Reporting Date Using As of December 31, 2014 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 $ 798,670 $ 798,670 $ 798,670 $ — $ — Investment securities available-for-sale 1,711,924 1,711,924 — 1,711,924 — Investment securities held-to-maturity 575,186 584,533 — 584,533 — Accrued interest receivable 27,063 27,063 — 27,063 — Mortgage servicing rights, net 14,038 21,434 — 21,434 — Net loans 4,823,243 4,800,725 — 4,770,231 30,494 Total financial assets $ 7,950,124 $ 7,944,349 $ 798,670 $ 7,115,185 $ 30,494 Financial liabilities: Total deposits, excluding time deposits $ 5,767,992 $ 5,767,992 $ 5,767,992 $ — $ — Time deposits 1,238,220 1,244,324 — 1,244,324 — Securities sold under repurchase agreements 502,250 502,250 — 502,250 — Other borrowed funds 9 9 — 9 — Accrued interest payable 5,833 5,833 — 5,833 — Long-term debt 38,067 37,781 — 37,781 — Subordinated debentures held by subsidiary trusts 82,477 75,734 — 75,734 — Total financial liabilities $ 7,634,848 $ 7,633,923 $ 5,767,992 $ 1,865,931 $ —

Business Combination (Details)

Business Combination (Details) $ in Thousands	Jul. 24, 2015	Mar. 26, 2015	Jul. 31, 2014	Jun. 30, 2015USD ($)	Dec. 31, 2014USD ($)
Business Acquisition [Line Items]
Assets				$ 8,386,218	$ 8,609,936
Loans and Leases Receivable, Net Amount				5,027,394	4,823,243
Deposits				6,804,401	$ 7,006,212
United Bank [Member]
Business Acquisition [Line Items]
Business Acquisition, Date of Acquisition Agreement		Mar. 26, 2015
Estimate of Payments to Acquire Businesses, Gross				$ 7,234
Number of Communities Adjacent to Existing Market Areas				3
Assets				$ 73,272
Loans and Leases Receivable, Net Amount				37,520
Deposits				$ 63,580
Number of Subsidiary Banks				1
Mountain West Bank
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Jul. 31, 2014
Goodwill, Purchase Accounting Adjustments				$ 1,199
Subsequent Event [Member] | United Bank [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Jul. 24, 2015

Amortized Cost and Approximate

Amortized Cost and Approximate Fair Values of Investment Securities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Schedule of Available for Sale and Held-to-Maturity Securities [Line Items]
Available-for-Sale Securities, Gross Realized Gains	$ 46	$ 18	$ 52	$ 243
Available-for-sale Securities, Gross Realized Losses	0	$ 1	0	$ 155
Available-for-Sale:
Available-for-Sale, Amortized Cost	1,587,953		1,587,953		$ 1,708,494
Available-for-sale Securities, Gross Unrealized Gain1	11,559		11,559		12,426
Available-for-sale Securities, Gross Unrealized Loss1	(6,769)		(6,769)		(8,996)
Available-for-Sale, Estimated Fair Value	1,592,743		1,592,743		1,711,924
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	546,690		546,690		575,186
Held-to-maturity Securities, Gross Unrealized Gain1	10,649		10,649		11,566
Held-to-maturity Securities, Gross Unrealized Loss1	(4,016)		(4,016)		(2,219)
Held-to-Maturity, Estimated Fair Value	553,323		553,323		584,533
Obligations of U.S. government agencies
Available-for-Sale:
Available-for-Sale, Amortized Cost	622,237		622,237		725,408
Available-for-sale Securities, Gross Unrealized Gain1	1,087		1,087		895
Available-for-sale Securities, Gross Unrealized Loss1	(2,304)		(2,304)		(5,370)
Available-for-Sale, Estimated Fair Value	621,020		621,020		720,933
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations
Available-for-Sale:
Available-for-Sale, Amortized Cost	965,430		965,430		982,764
Available-for-sale Securities, Gross Unrealized Gain1	10,468		10,468		11,526
Available-for-sale Securities, Gross Unrealized Loss1	(4,463)		(4,463)		(3,624)
Available-for-Sale, Estimated Fair Value	971,435		971,435		990,666
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	314,326		314,326		353,176
Held-to-maturity Securities, Gross Unrealized Gain1	5,945		5,945		5,563
Held-to-maturity Securities, Gross Unrealized Loss1	(3,288)		(3,288)		(1,758)
Held-to-Maturity, Estimated Fair Value	316,983		316,983		356,981
Private mortgage-backed securities
Available-for-Sale:
Available-for-Sale, Amortized Cost	286		286		322
Available-for-sale Securities, Gross Unrealized Gain1	4		4		5
Available-for-sale Securities, Gross Unrealized Loss1	(2)		(2)		(2)
Available-for-Sale, Estimated Fair Value	288		288		325
State, county and municipal securities
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	181,642		181,642		188,941
Held-to-maturity Securities, Gross Unrealized Gain1	4,644		4,644		5,949
Held-to-maturity Securities, Gross Unrealized Loss1	(524)		(524)		(386)
Held-to-Maturity, Estimated Fair Value	185,762		185,762		194,504
Corporate securities
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	50,310		50,310		32,565
Held-to-maturity Securities, Gross Unrealized Gain1	59		59		54
Held-to-maturity Securities, Gross Unrealized Loss1	(204)		(204)		(75)
Held-to-Maturity, Estimated Fair Value	50,165		50,165		32,544
Other Investments
Held-to-Maturity:
Held-to-Maturity, Amortized Cost	412		412		504
Held-to-maturity Securities, Gross Unrealized Gain1	1		1		0
Held-to-maturity Securities, Gross Unrealized Loss1	0		0		0
Held-to-Maturity, Estimated Fair Value	$ 413		$ 413		$ 504

Investment Securities Realized

Investment Securities Realized Gains (Losses) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$ 46	$ 18	$ 52	$ 243
Gross realized losses	$ 0	$ 1	$ 0	$ 155

Investment Securities Gross Unr

Investment Securities Gross Unrealized Losses and Fair Values of Investment Securities (Details) $ in Thousands	Jun. 30, 2015USD ($)securities	Dec. 31, 2014USD ($)securities
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 360,915	$ 355,102
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(1,940)	(1,589)
Available-for-Sale, 12 Months or More Fair Value	373,131	460,753
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(4,829)	(7,407)
Available-for-Sale, Total Fair Value	734,046	815,855
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(6,769)	(8,996)
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	136,004	83,935
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(3,657)	(1,846)
Held-to-Maturity, 12 Months or More Fair Value	13,513	20,097
Held-to-Maturity, 12 Months or More Gross Unrealized Losses	(359)	(373)
Held-to-Maturity, Total Fair Value	149,517	104,032
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	$ (4,016)	$ (2,219)
Available-for-Sale and Held-to-Maturity:
Investment Securities in an Unrealized Loss Position (Number of Securities) | securities	190	154
Obligations of U.S. government agencies
Available-for-Sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 106,516	$ 135,888
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(460)	(702)
Available-for-Sale, 12 Months or More Fair Value	239,339	309,283
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(1,844)	(4,668)
Available-for-Sale, Total Fair Value	345,855	445,171
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(2,304)	(5,370)
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	254,399	219,214
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(1,480)	(887)
Available-for-Sale, 12 Months or More Fair Value	133,709	151,380
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(2,983)	(2,737)
Available-for-Sale, Total Fair Value	388,108	370,594
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(4,463)	(3,624)
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	85,286	61,201
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(3,288)	(1,758)
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	85,286	61,201
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(3,288)	(1,758)
State, county and municipal securities
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	19,427	7,979
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(165)	(13)
Held-to-Maturity, 12 Months or More Fair Value	13,513	20,097
Held-to-Maturity, 12 Months or More Gross Unrealized Losses	(359)	(373)
Held-to-Maturity, Total Fair Value	32,940	28,076
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(524)	(386)
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	83	90
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1	(2)	(2)
Available-for-Sale, Total Fair Value	83	90
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1	(2)	(2)
Corporate securities
Held-to-Maturity:
Held-to-Maturity, Less than 12 Months Fair Value	31,291	14,755
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1	(204)	(75)
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	31,291	14,755
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1	$ (204)	$ (75)

Maturities of Investment Securi

Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Rolling Maturity
Available-for-Sale Amortized Cost, Within One Year	$ 321,079
Available-for-Sale Amortized Cost, After One Year but Within Five Years	1,189,454
Available-for-Sale Amortized Cost, After Five Years but Within Ten Years	58,106
Available-for-Sale Amortized Cost, After Ten Years	19,314
Available-for-Sale, Amortized Cost	1,587,953	$ 1,708,494
Available-for-sale Securities, Debt Maturities, Fair Value, Rolling Maturity
Available-for-Sale Estimated Fair Value, Within One Year	322,976
Available-for-Sale Estimated Fair Value, After One Year but Within Five Years	1,192,101
Available-for-Sale Estimated Fair Value, After Ten Years	58,232
Available-for-Sale Estimated Fair Value, After Five Years but Within Ten Years	19,434
Available-for-Sale, Estimated Fair Value	1,592,743	1,711,924
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount
Held-to-Maturity Amortized Cost, Within One Year	97,639
Held-to-Maturity Amortized Cost, After One Year but Within Five Years	273,778
Held-to-Maturity Amortized Cost, After Five Years but Within Ten Years	125,446
Held-to-Maturity Amortized Cost, After Ten Years	49,827
Held-to-Maturity, Amortized Cost	546,690	575,186
Held-to-maturity Securities, Debt Maturities, Fair Value, Rolling Maturity
Held-to-Maturity Estimated Fair Value, Within One Year	98,594
Held-to-Maturity Estimated Fair Value, After One Year but Within Five Years	276,390
Held-to-Maturity Estimated Fair Value, After Five Years but Within Ten Years	127,706
Held-to-Maturity Estimated Fair Value, After Ten Years	50,633
Held-to-Maturity, Estimated Fair Value	553,323	$ 584,533
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	104,832
Investment Securities Primarily Classified as Available-for-Sale, Fair Value, After One Year but Within Five Years	104,923
Callable Structured Notes
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	4,996
Investment Securities Primarily Classified as Available-for-Sale, Fair Value, After One Year but Within Five Years	$ 5,004

Schedule of Loans by Class (Det

Schedule of Loans by Class (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Loans and Leases Receivable [Line Items]
Loans held for investment	$ 5,028,624	$ 4,856,615
Mortgage loans held for sale	75,322	40,828
Total loans	5,103,946	4,897,443
Commercial real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	1,704,073	1,639,422
Land acquisition & development construction real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	211,889	220,443
Residential construction real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	101,023	96,580
Commercial construction real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	90,316	101,246
Total construction loans
Loans and Leases Receivable [Line Items]
Loans held for investment	403,228	418,269
Residential real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	999,038	999,903
Agricultural real estate
Loans and Leases Receivable [Line Items]
Loans held for investment	158,506	167,659
Total real estate loans
Loans and Leases Receivable [Line Items]
Loans held for investment	3,264,845	3,225,253
Indirect consumer
Loans and Leases Receivable [Line Items]
Loans held for investment	589,479	552,863
Other consumer
Loans and Leases Receivable [Line Items]
Loans held for investment	144,919	144,141
Credit card consumer
Loans and Leases Receivable [Line Items]
Loans held for investment	64,728	65,467
Total consumer loans
Loans and Leases Receivable [Line Items]
Loans held for investment	799,126	762,471
Total loans	799,126	762,471
Commercial
Loans and Leases Receivable [Line Items]
Loans held for investment	819,119	740,073
Total loans	819,119	740,073
Agricultural
Loans and Leases Receivable [Line Items]
Loans held for investment	142,629	124,859
Other, including overdrafts
Loans and Leases Receivable [Line Items]
Loans held for investment	$ 2,905	$ 3,959

Loans Schedule of Loans Acquire

Loans Schedule of Loans Acquired from Business Combinations (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Jun. 30, 2014
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities [Abstract]
Outstanding Balance	$ 35,555	$ 0
Carrying Amount Net, Accrual Status	22,293	0
Carrying Amount Net, Non Accrual Status	0	0
Total Carrying Value	$ 22,293	$ 0

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		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning Balance	$ 6,980	$ 0	$ 5,781	$ 0
Accretion Income	(807)	0	(1,355)	0
Reductions Due to Exit Events	0	0	(396)	0
Reclassifications from (to) nonaccretable differences	1,309	0	3,452	0
Ending Balance	$ 7,482	$ 0	$ 7,482	$ 0

Schedule of Recorded Investment

Schedule of Recorded Investment in Past Due Loans by Class (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Mortgage loans held for sale	$ 75,322		$ 75,322		$ 40,828
Loans held for investment	5,028,624		5,028,624		4,856,615
Total loans	5,103,946		5,103,946		4,897,443
Interest Income on Non-Accrual Loans if Accrued	875	$ 1,061	1,613	$ 2,182
Commercial real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	8,037		8,037		6,632
Current Loans	1,669,445		1,669,445		1,605,421
Non-accrual Loans	26,591		26,591		27,369
Loans held for investment	1,704,073		1,704,073		1,639,422
Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,507		1,507		1,222
Current Loans	202,620		202,620		210,969
Non-accrual Loans	7,762		7,762		8,252
Loans held for investment	211,889		211,889		220,443
Residential construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	417		417		475
Current Loans	100,274		100,274		95,833
Non-accrual Loans	332		332		272
Loans held for investment	101,023		101,023		96,580
Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	0		0		100
Current Loans	86,874		86,874		98,582
Non-accrual Loans	3,442		3,442		2,564
Loans held for investment	90,316		90,316		101,246
Total construction loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,924		1,924		1,797
Current Loans	389,768		389,768		405,384
Non-accrual Loans	11,536		11,536		11,088
Loans held for investment	403,228		403,228		418,269
Residential real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	6,016		6,016		9,376
Current Loans	990,453		990,453		987,735
Non-accrual Loans	2,569		2,569		2,792
Loans held for investment	999,038		999,038		999,903
Agricultural real estate
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,136		1,136		1,860
Current Loans	150,586		150,586		158,957
Non-accrual Loans	6,784		6,784		6,842
Loans held for investment	158,506		158,506		167,659
Total real estate loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	17,113		17,113		19,665
Current Loans	3,200,252		3,200,252		3,157,497
Non-accrual Loans	47,480		47,480		48,091
Loans held for investment	3,264,845		3,264,845		3,225,253
Indirect consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	3,915		3,915		3,723
Current Loans	585,200		585,200		548,757
Non-accrual Loans	364		364		383
Loans held for investment	589,479		589,479		552,863
Other consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	935		935		1,160
Current Loans	143,241		143,241		142,432
Non-accrual Loans	743		743		549
Loans held for investment	144,919		144,919		144,141
Credit card consumer
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	1,030		1,030		968
Current Loans	63,684		63,684		64,484
Non-accrual Loans	14		14		15
Loans held for investment	64,728		64,728		65,467
Total consumer loans
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	5,880		5,880		5,851
Current Loans	792,125		792,125		755,673
Non-accrual Loans	1,121		1,121		947
Loans held for investment	799,126		799,126		762,471
Total loans	799,126		799,126		762,471
Commercial
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	9,287		9,287		4,800
Current Loans	788,210		788,210		722,575
Non-accrual Loans	21,622		21,622		12,698
Loans held for investment	819,119		819,119		740,073
Total loans	819,119		819,119		740,073
Agricultural
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	740		740		1,125
Current Loans	141,264		141,264		123,288
Non-accrual Loans	625		625		446
Loans held for investment	142,629		142,629		124,859
Other, including overdrafts
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	311		311		0
Current Loans	2,594		2,594		3,959
Non-accrual Loans	0		0		0
Loans held for investment	2,905		2,905		3,959
Loans held for investment
Loans and Leases Receivable Recorded Investment, Past Due [Line Items]
Total Loans 30 or More Days Past Due	33,331		33,331		31,441
Current Loans	4,924,445		4,924,445		4,762,992
Non-accrual Loans	70,848		70,848		62,182
Loans held for investment	5,028,624		5,028,624		4,856,615
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	75,322		75,322		40,828
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	33,331		33,331		31,441
Current Loans	4,999,767		4,999,767		4,803,820
Non-accrual Loans	70,848		70,848		62,182
Total loans	5,103,946		5,103,946		4,897,443
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	5,123		5,123		4,692
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	1,075		1,075		839
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	417		417		0
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	0		0		100
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	1,492		1,492		939
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	3,563		3,563		6,969
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	875		875		1,624
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	11,053		11,053		14,224
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	3,382		3,382		3,235
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	785		785		988
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	415		415		369
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	4,582		4,582		4,592
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	8,285		8,285		3,659
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	700		700		1,125
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	24,620		24,620		23,600
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	24,620		24,620		23,600
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	2,803		2,803		1,609
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	276		276		383
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		475
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	0		0		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	276		276		858
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	1,524		1,524		645
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	261		261		236
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	4,864		4,864		3,348
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	507		507		482
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	121		121		140
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	224		224		284
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	852		852		906
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	812		812		994
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	30		30		0
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	6,558		6,558		5,248
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	6,558		6,558		5,248
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	111		111		331
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	156		156		0
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	0		0		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	156		156		0
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	929		929		1,762
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	0		0		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	1,196		1,196		2,093
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	26		26		6
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	29		29		32
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	391		391		315
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	446		446		353
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	190		190		147
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	10		10		0
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		0
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	2,153		2,153		2,593
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	$ 2,153		$ 2,153		$ 2,593

Loans Schedule of Recorded Inve

Loans Schedule of Recorded Investment in Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	$ 133,299		$ 133,299		$ 87,240
Recorded Investment With No Allowance	58,800		58,800		57,050
Recorded Investment With Allowance	41,693		41,693		21,430
Total Recorded Investment	100,493		100,493		78,480
Related Allowance	8,721		8,721		5,792
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	86,438	$ 103,910	82,923	$ 107,961
Income Recognized	357	300	555	555
Interest Income on Impaired Loans If Interest Had Been Accrued	1,045	1,301	2,011	2,412
Commercial real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	60,786		60,786		41,603
Recorded Investment With No Allowance	31,201		31,201		28,143
Recorded Investment With Allowance	17,201		17,201		11,246
Total Recorded Investment	48,402		48,402		39,389
Related Allowance	1,810		1,810		1,608
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	39,513	57,588	40,652	60,870
Income Recognized	211	241	361	457
Land acquisition & development construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	22,630		22,630		12,511
Recorded Investment With No Allowance	6,452		6,452		7,262
Recorded Investment With Allowance	5,915		5,915		1,615
Total Recorded Investment	12,367		12,367		8,877
Related Allowance	569		569		574
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	8,664	13,563	8,720	14,554
Income Recognized	12	11	22	22
Residential construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	969		969		459
Recorded Investment With No Allowance	332		332		272
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	332		332		272
Related Allowance	0		0		0
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	338	785	302	1,051
Income Recognized	0	0	0	0
Commercial construction real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	3,796		3,796		2,729
Recorded Investment With No Allowance	426		426		253
Recorded Investment With Allowance	1,590		1,590		2,442
Total Recorded Investment	2,016		2,016		2,695
Related Allowance	1,606		1,606		904
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	3,492	1,471	3,133	918
Income Recognized	0	2	2	4
Total construction loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	27,395		27,395		15,699
Recorded Investment With No Allowance	7,210		7,210		7,787
Recorded Investment With Allowance	7,505		7,505		4,057
Total Recorded Investment	14,715		14,715		11,844
Related Allowance	2,175		2,175		1,478
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	12,494	15,819	12,155	16,523
Income Recognized	12	13	24	26
Residential real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	5,442		5,442		2,959
Recorded Investment With No Allowance	2,291		2,291		2,452
Recorded Investment With Allowance	1,429		1,429		341
Total Recorded Investment	3,720		3,720		2,793
Related Allowance	127		127		143
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	3,014	5,852	2,719	5,969
Income Recognized	1	1	2	3
Agricultural real estate
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	9,094		9,094		8,844
Recorded Investment With No Allowance	6,396		6,396		6,444
Recorded Investment With Allowance	2,202		2,202		2,305
Total Recorded Investment	8,598		8,598		8,749
Related Allowance	712		712		732
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	8,572	9,747	8,666	9,830
Income Recognized	13	25	35	29
Total real estate loans
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	102,717		102,717		69,105
Recorded Investment With No Allowance	47,098		47,098		44,826
Recorded Investment With Allowance	28,337		28,337		17,949
Total Recorded Investment	75,435		75,435		62,775
Related Allowance	4,824		4,824		3,961
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	63,593	89,006	64,192	93,192
Income Recognized	237	280	422	515
Commercial
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	28,472		28,472		16,904
Recorded Investment With No Allowance	11,275		11,275		11,882
Recorded Investment With Allowance	12,298		12,298		2,644
Total Recorded Investment	23,573		23,573		14,526
Related Allowance	3,279		3,279		1,190
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	21,841	14,162	17,874	14,231
Income Recognized	112	14	120	28
Agricultural
Impaired Financing Receivable, Unpaid Principal Balance
Unpaid Total Principal Balance	2,110		2,110		1,231
Recorded Investment With No Allowance	427		427		342
Recorded Investment With Allowance	1,058		1,058		837
Total Recorded Investment	1,485		1,485		1,179
Related Allowance	618		618		$ 641
Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income
Average Recorded Investment	1,004	742	857	538
Income Recognized	$ 8	$ 6	$ 13	$ 12

Schedule of Loans Renegotiated

Schedule of Loans Renegotiated in Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015USD ($)notes	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)notes	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Loans Renegotiated in Troubled Debt Restructurings	$ 37,363		$ 37,363		$ 44,227
Loans Renegotiated in Troubled Debt Restructurings, Non-Accrual Loans	22,236		22,236		23,275
Loans Renegotiated in Troubled Debt Restructurings, Accrual Loans	$ 15,127		$ 15,127		$ 20,952
Number of Notes | notes	0		1
Financing Receivable, Modifications, Pre-Modification Recorded Investment			$ 10
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 0	$ 0	0	$ 0
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
Extension of terms or maturity
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			10
Interest rate adjustment
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			0
Other
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			$ 0
Commercial real estate
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | notes	0		1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	$ 0		$ 1,822
Commercial
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Number of Notes | notes			1
Financing Receivable, Modifications, Pre-Modification Recorded Investment			$ 10
Commercial | Interest only period
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			0
Commercial | Extension of terms or maturity
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			10
Commercial | Interest rate adjustment
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			0
Commercial | Other
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			$ 0

Schedule of Recorded Investme45

Schedule of Recorded Investment in Criticized Loans by Class and Credit Quality Indicator (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	$ 5,028,624	$ 4,856,615
Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,704,073	1,639,422
Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	211,889	220,443
Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	101,023	96,580
Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	90,316	101,246
Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	403,228	418,269
Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	999,038	999,903
Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	158,506	167,659
Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	3,264,845	3,225,253
Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	589,479	552,863
Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	144,919	144,141
Credit card consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	64,728	65,467
Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	799,126	762,471
Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	819,119	740,073
Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	142,629	124,859
Other Assets Especially Mentioned
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	155,707	154,084
Other Assets Especially Mentioned | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	83,194	84,533
Other Assets Especially Mentioned | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	13,426	11,826
Other Assets Especially Mentioned | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	857	2,029
Other Assets Especially Mentioned | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	0	39
Other Assets Especially Mentioned | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	14,283	13,894
Other Assets Especially Mentioned | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	8,434	10,473
Other Assets Especially Mentioned | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	9,826	10,122
Other Assets Especially Mentioned | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	115,737	119,022
Other Assets Especially Mentioned | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	843	916
Other Assets Especially Mentioned | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	557	553
Other Assets Especially Mentioned | Credit card consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	0	0
Other Assets Especially Mentioned | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,400	1,469
Other Assets Especially Mentioned | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	34,776	25,766
Other Assets Especially Mentioned | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	3,794	7,827
Substandard
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	159,899	163,675
Substandard | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	85,323	83,448
Substandard | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	14,190	15,016
Substandard | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,165	2,666
Substandard | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	409	253
Substandard | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	16,764	17,935
Substandard | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	9,387	10,848
Substandard | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	14,838	12,328
Substandard | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	126,312	124,559
Substandard | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,454	1,590
Substandard | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	930	1,085
Substandard | Credit card consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	0	348
Substandard | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,384	3,023
Substandard | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	24,519	32,433
Substandard | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	6,684	3,660
Doubtful
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	31,701	34,854
Doubtful | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	7,952	15,246
Doubtful | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,031	2,507
Doubtful | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	29	0
Doubtful | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	3,161	2,442
Doubtful | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	5,221	4,949
Doubtful | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,002	1,121
Doubtful | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	595	612
Doubtful | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	14,770	21,928
Doubtful | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	161	121
Doubtful | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	349	432
Doubtful | Credit card consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	0	1,263
Doubtful | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	510	1,816
Doubtful | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	15,691	10,273
Doubtful | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	730	837
Total Criticized Loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	347,307	352,613
Total Criticized Loans | Commercial real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	176,469	183,227
Total Criticized Loans | Land acquisition & development construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	29,647	29,349
Total Criticized Loans | Residential construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	3,051	4,695
Total Criticized Loans | Commercial construction real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	3,570	2,734
Total Criticized Loans | Total construction loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	36,268	36,778
Total Criticized Loans | Residential real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	18,823	22,442
Total Criticized Loans | Agricultural real estate
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	25,259	23,062
Total Criticized Loans | Total real estate loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	256,819	265,509
Total Criticized Loans | Indirect consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	2,458	2,627
Total Criticized Loans | Other consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	1,836	2,070
Total Criticized Loans | Credit card consumer
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	0	1,611
Total Criticized Loans | Total consumer loans
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	4,294	6,308
Total Criticized Loans | Commercial
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	74,986	68,472
Total Criticized Loans | Agricultural
Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items]
Loans held for investment	$ 11,208	$ 12,324

Schedule of Allowance for Loan

Schedule of Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Certain Loans and Debt Securities Acquired in Transfer, Allowance for Credit Losses Due to Subsequent Impairment					$ 501	$ 287
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 75,336	$ 81,371	$ 74,200	$ 85,339
Provision charged to operating expense	1,340	(2,001)	2,435	(7,001)
Less loans charged-off	(1,508)	(2,626)	(3,368)	(5,417)
Add back recoveries of loans previously charged-off	1,384	1,522	3,285	5,345
Ending balance	76,552	78,266	76,552	78,266
Allowance for loan losses:
Loans individually evaluated for impairment					8,721	5,792
Loans collectively evaluated for impairment					67,831	68,408
Ending balance	75,336	81,371	74,200	85,339	76,552	74,200
Total loans:
Individually evaluated for impairment					100,493	78,480
Individually evaluated for impairment					5,003,453	4,818,963
Total loans					5,103,946	4,897,443
Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	53,659	59,830	53,884	63,923
Provision charged to operating expense	461	(2,011)	(570)	(5,386)
Less loans charged-off	(610)	(1,158)	(795)	(2,243)
Add back recoveries of loans previously charged-off	425	651	1,416	1,018
Ending balance	53,935	57,312	53,935	57,312
Allowance for loan losses:
Loans individually evaluated for impairment					4,824	3,961
Loans collectively evaluated for impairment					49,111	49,923
Ending balance	53,659	59,830	53,884	63,923	53,935	53,884
Total loans:
Individually evaluated for impairment					75,435	62,775
Individually evaluated for impairment					3,264,732	3,203,306
Total loans					3,340,167	3,266,081
Total consumer loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,499	5,377	5,035	6,193
Provision charged to operating expense	646	346	1,771	(232)
Less loans charged-off	(837)	(934)	(2,138)	(1,780)
Add back recoveries of loans previously charged-off	520	558	1,160	1,166
Ending balance	5,828	5,347	5,828	5,347
Allowance for loan losses:
Loans individually evaluated for impairment					0	0
Loans collectively evaluated for impairment					5,828	5,035
Ending balance	5,499	5,377	5,035	6,193	5,828	5,035
Total loans:
Individually evaluated for impairment					0	0
Individually evaluated for impairment					799,126	762,471
Total loans					799,126	762,471
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	15,196	15,701	14,307	14,747
Provision charged to operating expense	224	(494)	1,217	(1,566)
Less loans charged-off	(61)	(534)	(435)	(1,330)
Add back recoveries of loans previously charged-off	438	313	708	3,135
Ending balance	15,797	14,986	15,797	14,986
Allowance for loan losses:
Loans individually evaluated for impairment					3,279	1,190
Loans collectively evaluated for impairment					12,518	13,117
Ending balance	15,196	15,701	14,307	14,747	15,797	14,307
Total loans:
Individually evaluated for impairment					23,573	14,526
Individually evaluated for impairment					795,546	725,547
Total loans					819,119	740,073
Agriculture
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	982	463	974	476
Provision charged to operating expense	9	158	17	183
Less loans charged-off	0	0	0	(64)
Add back recoveries of loans previously charged-off	1	0	1	26
Ending balance	992	621	992	621
Allowance for loan losses:
Loans individually evaluated for impairment					618	641
Loans collectively evaluated for impairment					374	333
Ending balance	982	463	974	476	992	974
Total loans:
Individually evaluated for impairment					1,485	1,179
Individually evaluated for impairment					141,144	123,680
Total loans					142,629	124,859
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
Allowance for loan losses:
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					2,905	3,959
Total loans					$ 2,905	$ 3,959

OREO (Details)

OREO (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	$ 65		$ 65
Real Estate Acquired Through Foreclosure [Roll Forward]
Beginning balance	15,134	$ 16,594	13,554	$ 15,504
Additions	1,139	984	4,396	4,399
Valuation adjustments	0	(10)	(106)	(10)
Dispositions	(4,500)	(1,143)	(6,071)	(3,468)
Ending balance	11,773	$ 16,425	11,773	$ 16,425
Residential real estate
Real Estate Acquired Through Foreclosure [Roll Forward]
Ending balance	$ 3,708		$ 3,708

Long Term Debt (Details)

Long Term Debt (Details) - Jun. 30, 2015 - USD ($) $ in Thousands	Total
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	Jan. 29, 2015
Debt Instrument, Maturity Date	Jul. 29, 2022
Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 4,960
Debt Instrument, Interest Rate, Stated Percentage	2.28%
Members' Equity	99.90%

Capital Stock (Details)

Capital Stock (Details) - USD ($) $ in Thousands	Apr. 03, 2015	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Class of Stock [Line Items]
Payments for Repurchase of Common Stock		$ 15,264	$ 8,764
Class A Common Stock
Class of Stock [Line Items]
Common Stock, Shares, Outstanding		21,720,287		21,928,932
Stock Repurchased and Retired During Period, Shares		565,875	325,418
Payments for Repurchase of Common Stock		$ 14,674	$ 8,143
Stock Repurchase Program, Remaining Authorized Repurchase Amount		434,125
Class A Common Stock | 2015 Equity Compensation Plan
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	2,000,000
Class B Common Stock
Class of Stock [Line Items]
Common Stock, Shares, Outstanding		23,786,296		23,859,483

Computation of Basic and Dilute

Computation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net Income (Loss) Available to Common Stockholders, Basic
Net income	$ 22,222	$ 21,077	$ 43,202	$ 42,470
Weighted Average Number of Shares Outstanding, Basic and Diluted
Weighted average common shares outstanding for basic earnings per share computation	45,143,122	44,044,260	45,260,104	44,021,166
Dilutive effect of stock-based compensation	463,564	531,703	582,935	573,689
Weighted average common shares outstanding for diluted earnings per common share computation	45,606,686	44,575,963	45,843,039	44,594,855
Earnings Per Share, Basic and Diluted
Basic earnings per common share	$ 0.49	$ 0.48	$ 0.95	$ 0.96
Diluted earnings per common share	$ 0.49	$ 0.47	$ 0.94	$ 0.95
Stock Options
Earnings Per Share, Basic and Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			0	0
Unvested Restricted Stock
Earnings Per Share, Basic and Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			166,362	107,651

Schedule of Actual Capital Amou

Schedule of Actual Capital Amounts and Ratios and Selected Minimum Regulatory Thresholds (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Total risk-based capital:
Actual Amount	$ 924,408	$ 897,769
Actual Ratio	15.40%	16.20%
Adequately Capitalized Amount	$ 481,244	$ 444,685
Adequately Capitalized Ratio	8.00%	8.00%
Well Capitalized Amount	$ 601,555	$ 555,856
Well Capitalized Ratio	10.00%	10.00%
Tier 1 risk-based capital:
Actual Amount	$ 835,198	$ 807,229
Actual Ratio	13.90%	14.50%
Adequately Capitalized Amount	$ 360,933	$ 222,343
Adequately Capitalized Ratio	6.00%	4.00%
Well Capitalized Amount	$ 481,244	$ 333,514
Well Capitalized Ratio	8.00%	6.00%
Common equity tier one risk-based capital:
Actual Amount	$ 755,198
Actual Ratio	12.60%
Adequately Capitalized Amount	$ 270,700
Adequately Capitalized Ratio	4.50%
Well Capitalized Amount	$ 391,011
Well Capitalized Ratio	6.50%
Leverage capital ratio:
Actual Amount	$ 835,198
Actual Ratio	10.10%	9.60%
Adequately Capitalized Amount	$ 330,350	$ 335,897
Adequately Capitalized Ratio	4.00%	4.00%
Well Capitalized Amount	$ 412,938	$ 419,871
Well Capitalized Ratio	5.00%	5.00%
FIB
Total risk-based capital:
Actual Amount	$ 857,522	$ 832,907
Actual Ratio	14.30%	15.10%
Adequately Capitalized Amount	$ 479,416	$ 442,468
Adequately Capitalized Ratio	8.00%	8.00%
Well Capitalized Amount	$ 599,270	$ 553,085
Well Capitalized Ratio	10.00%	10.00%
Tier 1 risk-based capital:
Actual Amount	$ 776,594	$ 754,708
Actual Ratio	13.00%	13.70%
Adequately Capitalized Amount	$ 359,562	$ 221,234
Adequately Capitalized Ratio	6.00%	4.00%
Well Capitalized Amount	$ 479,416	$ 331,851
Well Capitalized Ratio	8.00%	6.00%
Common equity tier one risk-based capital:
Actual Amount	$ 776,594
Actual Ratio	13.00%
Adequately Capitalized Amount	$ 269,671
Adequately Capitalized Ratio	4.50%
Well Capitalized Amount	$ 389,525
Well Capitalized Ratio	6.50%
Leverage capital ratio:
Actual Amount	$ 776,594
Actual Ratio	9.40%	9.20%
Adequately Capitalized Amount	$ 329,180	$ 330,006
Adequately Capitalized Ratio	4.00%	4.00%
Well Capitalized Amount	$ 411,475	$ 412,507
Well Capitalized Ratio	5.00%	5.00%

Legal Proceedings (Details)

Legal Proceedings (Details) - Pending Litigation - Kelly Logging Inc. v. First Interstate Bank - USD ($) $ in Thousands	Apr. 21, 2015	Oct. 01, 2014	Aug. 31, 2014	Jun. 30, 2015
Loss Contingencies [Line Items]
Loss Contingency, Damages Awarded, Value		$ 17,047	$ 17,047
Awarded Plaintiff Attorney's Fees	$ 7,500
Awarded Plaintiff Costs	91
Litigation Settlement, Amount	$ 24,638
Loss Contingency, Compensatory Damages Awarded, Value			287
Loss Contingency, Punitive Damages Awarded, Value			$ 16,760
Loss Contingency Accrual				$ 4,000

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Thousands	Jun. 30, 2015USD ($)
Construction Contracts
Unrecorded Unconditional Purchase Obligation [Line Items]
Commitments to Purchase	$ 2,433

Financial Instruments with Of54

Financial Instruments with Off-Balance Sheet Risk (Details) $ in Thousands	Jun. 30, 2015USD ($)
Entity Information [Line Items]
Credit Extension Commitments	$ 995,388
Credit Extension Commitments, Beyond One Year	357,999
Standby Letters of Credit
Entity Information [Line Items]
Credit Extension Commitments	58,105
Unused Credit Card Lines
Entity Information [Line Items]
Credit Extension Commitments	$ 528,943

Supplemental Cash Flow Informat

Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Supplemental Cash Flow Information [Abstract]
Transferred Loans to OREO	$ 4,396	$ 4,399
Transferred Loans to Mortgage Servicing Assets	1,792	$ 1,024
Transfer of Portfolio Loans and Leases to Held-for-sale	$ 10,619

Schedule of Comprehensive Incom

Schedule of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Change in net unrealized Gain during period:
Change in net unrealized gain during period, before tax amount	$ (9,196)	$ 2,816	$ 1,412	$ 17,167
Change in net unrealized gain during period, tax expense (benefit)	(3,618)	1,108	555	6,755
Change in net unrealized gain during period, net of tax amount	(5,578)	1,708	857	10,412
Reclassification adjustment for gains included in net income:
Reclassification adjustment for gains included in net income, before tax amount	(46)	(17)	(52)	(88)
Reclassification adjustment for gains included in net income, tax expense (benefit)	(18)	(7)	(20)	(35)
Reclassification adjustment for gains included in net income, net of tax amount	(28)	(10)	(32)	(53)
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	451	0	902	0
Other Comprehensive Income (Loss), Transfers from Held-to-maturity to Available-for-Sale Securities, Tax	177	0	355	0
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	274	0	547	0
Change in net actuarial loss:
Change in net actuarial loss, before tax amount	13	35	28	70
Change in net actuarial loss, tax expense (benefit)	5	14	11	28
Change in net actuarial loss, net of tax amount	8	21	17	42
Other comprehensive income (loss):
Other comprehensive income (loss), before tax	(8,778)	2,834	2,290	17,149
Total other comprehensive income, tax expense (benefit)	(3,454)	1,115	901	6,748
Total other comprehensive income, net of tax amount	$ (5,324)	$ 1,719	$ 1,389	$ 10,401

Schedule of Accumulated Other C

Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Net accumulated other comprehensive income:
Net unrealized gain on investment securities available-for-sale	$ (749)	$ (2,121)
Net actuarial loss on defined benefit post-retirement benefit plans	(396)	(413)
Net accumulated other comprehensive income	$ (1,145)	$ (2,534)

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		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real Estate Acquired Through Foreclosure, Valuation Adjustments	$ 0	$ 10	$ 106	$ 10
Related Allowance	8,721		8,721		$ 5,792
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 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 Non-recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	50,131		50,131		30,494
Other real estate owned	5,623		5,623		4,554
Real Estate Acquired Through Foreclosure, Valuation Adjustments			106	$ 10
Long-lived assets to be disposed of by sale	1,083		1,083		1,083
Related Allowance	8,721		8,721		5,792
Impaired Financing Receivable, Related Allowance, Partial Loan Charge-Offs	11,975		11,975		8,760
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	621,020		621,020		720,933
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	971,435		971,435		990,666
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	288		288		325
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
Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,592,743		1,592,743		1,711,924
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	50,131		50,131		30,494
Other real estate owned	5,623		5,623		4,554
Long-lived assets to be disposed of by sale	1,083		1,083		1,083
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
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	1,592,743		1,592,743		1,711,924
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
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	50,131		50,131		30,494
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	621,020		621,020		720,933
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	971,435		971,435		990,666
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	288		288		325
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	1,592,743		1,592,743		1,711,924
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	70,827		70,827		45,046
Long-lived assets to be disposed of by sale	1,785		1,785		1,785
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	$ 702		$ 702		$ 702

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Inputs, Quantitative Information (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
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%)	(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	(51.00%)	(51.00%)
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	(19.00%)	(19.00%)
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	(0.00%)	(0.00%)
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	(50.00%)	(50.00%)
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	(15.00%)	(15.00%)
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%)	(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%)	(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	(5.00%)	(5.00%)
Estimated Fair Value | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	$ 50,131	$ 30,494
Long-lived assets to be disposed of by sale	1,083	1,083
Other real estate owned	$ 5,623	$ 4,554

Schedule of Estimated Fair Valu

Schedule of Estimated Fair Values of Financial Instruments by Level of Valuation Inputs (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Financial assets:
Investment securities held-to-maturity	$ 553,323	$ 584,533
Carrying Amount
Financial assets:
Cash and cash equivalents	506,434	798,670
Investment securities available-for-sale	1,592,743	1,711,924
Investment securities held-to-maturity	546,690	575,186
Accrued interest receivable	29,008	27,063
Mortgage servicing rights	14,654	14,038
Net loans	5,027,394	4,823,243
Total financial assets	7,716,923	7,950,124
Financial liabilities:
Total deposits, excluding time deposits	5,655,166	5,767,992
Time deposits	1,149,235	1,238,220
Securities sold under repurchase agreements	469,145	502,250
Other borrowed funds	3	9
Accrued interest payable	5,366	5,833
Long-term debt	43,068	38,067
Subordinated debentures held by subsidiary trusts	82,477	82,477
Total financial liabilities	7,404,460	7,634,848
Estimated Fair Value
Financial assets:
Cash and cash equivalents	506,434	798,670
Investment securities available-for-sale	1,592,743	1,711,924
Investment securities held-to-maturity	553,323	584,533
Accrued interest receivable	29,008	27,063
Mortgage servicing rights	28,320	21,434
Net loans	5,000,935	4,800,725
Total financial assets	7,710,763	7,944,349
Financial liabilities:
Total deposits, excluding time deposits	5,655,166	5,767,992
Time deposits	1,153,809	1,244,324
Securities sold under repurchase agreements	469,145	502,250
Other borrowed funds	3	9
Accrued interest payable	5,366	5,833
Long-term debt	41,584	37,781
Subordinated debentures held by subsidiary trusts	76,393	75,734
Total financial liabilities	7,401,466	7,633,923
Quoted Prices in Active Markets for Identical Assets (Level 1) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	506,434	798,670
Investment securities available-for-sale	0	0
Investment securities held-to-maturity	0	0
Accrued interest receivable	0	0
Mortgage servicing rights	0	0
Net loans	0	0
Total financial assets	506,434	798,670
Financial liabilities:
Total deposits, excluding time deposits	5,655,166	5,767,992
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
Total financial liabilities	5,655,166	5,767,992
Significant Other Observable Inputs (Level 2) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	0	0
Investment securities available-for-sale	1,592,743	1,711,924
Investment securities held-to-maturity	553,323	584,533
Accrued interest receivable	29,008	27,063
Mortgage servicing rights	28,320	21,434
Net loans	4,950,804	4,770,231
Total financial assets	7,154,198	7,115,185
Financial liabilities:
Total deposits, excluding time deposits	0	0
Time deposits	1,153,809	1,244,324
Securities sold under repurchase agreements	469,145	502,250
Other borrowed funds	3	9
Accrued interest payable	5,366	5,833
Long-term debt	41,584	37,781
Subordinated debentures held by subsidiary trusts	76,393	75,734
Total financial liabilities	1,746,300	1,865,931
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
Net loans	50,131	30,494
Total financial assets	50,131	30,494
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
Total financial liabilities	$ 0	$ 0

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event [Member] - $ / shares	Aug. 14, 2015	Aug. 03, 2015	Jul. 24, 2015	Jul. 23, 2015
Class A Common Stock
Subsequent Event [Line Items]
Dividends Payable, Date Declared				Jul. 23, 2015
Dividends Payable, Amount Per Share				$ 0.20
Dividends Payable, Date to be Paid	Aug. 14, 2015
Dividends Payable, Date of Record		Aug. 3, 2015
United Bank [Member]
Subsequent Event [Line Items]
Business Acquisition, Effective Date of Acquisition			Jul. 24, 2015

Uncategorized Items - fibk-2015

Label	Element	Value
Mortgage Servicing Rights (MSR) Impairment (Recovery)	us-gaap_MortgageServicingRightsMSRImpairmentRecovery	$ (11)
Mortgage Servicing Rights (MSR) Impairment (Recovery)	us-gaap_MortgageServicingRightsMSRImpairmentRecovery	(56)
Gain (Loss) on Sale of Debt Investments	us-gaap_GainLossOnSaleOfDebtInvestments	17
Gain (Loss) on Sale of Debt Investments	us-gaap_GainLossOnSaleOfDebtInvestments	$ 46