Glacier Bancorp (GBCI) 10-K 28 Feb 14 2013 Q4 Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Feb. 13, 2014	Jun. 30, 2013
Document and Entity Information [Abstract]	'	'	'
Entity Registrant Name	'GLACIER BANCORP INC	'	'
Entity Central Index Key	'0000868671	'	'
Document Type	'10-K	'	'
Document Period End Date	31-Dec-13	'	'
Amendment Flag	'false	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'Q4	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Entity Public Float	'	'	$1,582,440,108
Entity Common Stock, Shares Outstanding	'	74,426,962	'

Consolidated_Statements_of_Fin

Consolidated Statements of Financial Condition (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
Assets	'	'
Cash on hand and in banks	$109,995	$123,270
Federal funds sold	10,527	0
Interest bearing cash deposits	35,135	63,770
Cash and cash equivalents	155,657	187,040
Investment securities, available-for-sale	3,222,829	3,683,005
Loans held for sale	46,738	145,501
Loans receivable	4,062,838	3,397,425
Allowance for loan and lease losses	-130,351	-130,854
Loans receivable, net	3,932,487	3,266,571
Premises and equipment, net	167,671	158,989
Other real estate owned	26,860	45,115
Accrued interest receivable	41,898	37,770
Deferred tax asset	43,549	20,394
Core deposit intangible, net	9,512	6,174
Goodwill	129,706	106,100
Non-marketable equity securities	52,192	48,812
Other assets	55,251	41,969
Total assets	7,884,350	7,747,440
Liabilities	'	'
Non-interest bearing deposits	1,374,419	1,191,933
Interest bearing deposits	4,205,548	4,172,528
Securities sold under agreements to repurchase	313,394	289,508
Federal Home Loan Bank advances	840,182	997,013
Other borrowed funds	8,387	10,032
Subordinated debentures	125,562	125,418
Accrued interest payable	3,505	4,675
Other liabilities	50,103	55,384
Total liabilities	6,921,100	6,846,491
Stockholders' Equity	'	'
Preferred shares, $0.01 par value per share, 1,000,000 shares authorized, none issued or outstanding	0	0
Common stock, $0.01 par value per share, 117,187,500 shares authorized	744	719
Paid-in capital	690,918	641,737
Retained earnings - substantially restricted	261,943	210,531
Accumulated other comprehensive income	9,645	47,962
Total stockholders’ equity	963,250	900,949
Total liabilities and stockholders’ equity	$7,884,350	$7,747,440
Number of common stock shares issued and outstanding	74,373,296	71,937,222

Consolidated_Statements_of_Fin1

Consolidated Statements of Financial Condition (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]	'	'
Preferred shares, par value	$0.01	$0.01
Preferred shares, authorized	1,000,000	1,000,000
Preferred shares, issued	0	0
Preferred shares, outstanding	0	0
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	117,187,500	117,187,500

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Interest Income	'	'	'
Residential real estate loans	$29,525	$30,850	$33,060
Commercial loans	127,450	121,425	130,249
Consumer and other loans	32,089	35,096	40,538
Investment securities	74,512	66,386	76,262
Total interest income	263,576	253,757	280,109
Interest Expense	'	'	'
Deposits	13,870	18,183	25,269
Securities sold under agreements to repurchase	867	1,308	1,353
Federal Home Loan Bank advances	10,610	12,566	12,687
Federal funds purchased and other borrowed funds	206	229	224
Subordinated debentures	3,205	3,428	4,961
Total interest expense	28,758	35,714	44,494
Net Interest Income	234,818	218,043	235,615
Provision for loan losses	6,887	21,525	64,500
Net interest income after provision for loan losses	227,931	196,518	171,115
Non-Interest Income	'	'	'
Service charges and other fees	49,478	45,343	44,194
Miscellaneous loan fees and charges	4,982	4,363	3,919
Gain on sale of loans	28,517	32,227	21,132
(Loss) gain on sale of investments	-299	0	346
Other income	10,369	9,563	8,608
Total non-interest income	93,047	91,496	78,199
Non-Interest Expense	'	'	'
Compensation and employee benefits	104,221	95,373	85,691
Occupancy and equipment	24,875	23,837	23,599
Advertising and promotions	6,913	6,413	6,469
Outsourced data processing	4,493	3,324	3,153
Other real estate owned	7,196	18,964	27,255
Regulatory assessments and insurance	6,362	7,313	9,583
Core deposit intangible amortization	2,401	2,110	2,473
Goodwill impairment charge	0	0	40,159
Other expense	38,856	36,087	33,742
Total non-interest expense	195,317	193,421	232,124
Income Before Income Taxes	125,661	94,593	17,190
Federal and state income tax expense (benefit)	30,017	19,077	-281
Net Income	$95,644	$75,516	$17,471
Basic earnings per share	$1.31	$1.05	$0.24
Diluted earnings per share	$1.31	$1.05	$0.24
Dividends declared per share	$0.60	$0.53	$0.52
Average outstanding shares - basic	73,191,713	71,928,570	71,915,073
Average outstanding shares - diluted	73,260,278	71,928,656	71,915,073

Statements_of_Comprehensive_In

Statements of Comprehensive Income (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Comprehensive Income [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Net Income	$26,546	$25,628	$22,702	$20,768	$20,758	$19,444	$18,981	$16,333	$95,644	$75,516	$17,471
Other Comprehensive (Loss) Income, Net of Tax	'	'	'	'	'	'	'	'	'	'	'
Unrealized (losses) gains on available-for-sale securities	'	'	'	'	'	'	'	'	-81,739	31,617	63,190
Reclassification adjustment for losses (gains) included in net income	'	'	'	'	'	'	'	'	299	0	-346
Net unrealized (losses) gains on securities	'	'	'	'	'	'	'	'	-81,440	31,617	62,844
Tax effect	'	'	'	'	'	'	'	'	31,680	-12,300	-24,444
Net of tax amount	'	'	'	'	'	'	'	'	-49,760	19,317	38,400
Unrealized gains (losses) on derivatives used for cash flow hedges	'	'	'	'	'	'	'	'	18,728	-7,926	-8,906
Tax effect	'	'	'	'	'	'	'	'	-7,285	3,084	3,465
Net of tax amount	'	'	'	'	'	'	'	'	11,443	-4,842	-5,441
Total other comprehensive (loss) income, net of tax	'	'	'	'	'	'	'	'	-38,317	14,475	32,959
Total Comprehensive Income	'	'	'	'	'	'	'	'	$57,327	$89,991	$50,430

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Stockholders' Equity (USD $)	Total	Common Stock	Paid-in Capital	Retained Earnings Substantially Restricted	Accumulated Other Comprehensive Income
In Thousands, except Share data
Balance at Dec. 31, 2010	$838,204	$719	$643,894	$193,063	$528
Balance, shares at Dec. 31, 2010	'	71,915,073	'	'	'
Net income	17,471	'	'	17,471	'
Comprehensive income (loss), accumulated other comprehensive income	32,959	'	'	'	32,959
Comprehensive income (loss), total	50,430	'	'	'	'
Cash dividends declared	-37,395	'	'	-37,395	'
Stock-based compensation and related taxes	-1,012	'	-1,012	'	'
Balance at Dec. 31, 2011	850,227	719	642,882	173,139	33,487
Balance, shares at Dec. 31, 2011	'	71,915,073	'	'	'
Net income	75,516	'	'	75,516	'
Comprehensive income (loss), accumulated other comprehensive income	14,475	'	'	'	14,475
Comprehensive income (loss), total	89,991	'	'	'	'
Cash dividends declared	-38,124	'	'	-38,124	'
Stock-based compensation and related taxes	-1,468	'	-1,468	'	'
Stock issuances under stock incentive plans, shares	'	22,149	'	'	'
Stock issuances under stock incentive plans, value	323	0	323	'	'
Balance at Dec. 31, 2012	900,949	719	641,737	210,531	47,962
Balance, shares at Dec. 31, 2012	71,937,222	71,937,222	'	'	'
Net income	95,644	'	'	95,644	'
Comprehensive income (loss), accumulated other comprehensive income	-38,317	'	'	'	-38,317
Comprehensive income (loss), total	57,327	'	'	'	'
Cash dividends declared	-44,232	'	'	-44,232	'
Stock-based compensation and related taxes	-335	'	-335	'	'
Stock issuances under stock incentive plans, shares	'	292,942	'	'	'
Stock issuances under stock incentive plans, value	4,507	3	4,504	'	'
Stock issued in connection with acquisitions, shares	'	2,143,132	'	'	'
Stock issued in connection with acquisitions, value	45,034	22	45,012	'	'
Balance at Dec. 31, 2013	$963,250	$744	$690,918	$261,943	$9,645
Balance, shares at Dec. 31, 2013	74,373,296	74,373,296	'	'	'

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash dividends declared per share	$0.60	$0.53	$0.52
Retained Earnings Substantially Restricted	'	'	'
Cash dividends declared per share	$0.60	$0.53	$0.52

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Activities	'	'	'
Net income	$95,644	$75,516	$17,471
Adjustments to reconcile net income to net cash provided by operating activities:	'	'	'
Provision for loan losses	6,887	21,525	64,500
Net amortization of investment securities premiums and discounts	64,066	71,992	38,035
Federal Home Loan Bank stock dividends	0	-5	-17
Loans held for sale originated or acquired	-918,451	-1,188,632	-824,089
Proceeds from sales of loans held for sale	1,084,799	1,204,431	842,337
Gain on sale of loans	-28,517	-32,227	-21,132
Loss (gain) on sale of investments	299	0	-346
Stock-based compensation expense, net of tax benefits	1,011	254	45
Excess tax deficiencies from stock-based compensation	223	8	0
Depreciation of premises and equipment	10,485	10,615	10,443
Loss on sale of other real estate owned and writedowns, net	1,450	13,311	19,727
Core deposit intangible amortization	2,401	2,110	2,473
Goodwill impairment charge	0	0	40,159
Deferred tax expense (benefit)	4,633	837	-13,308
Net increase in accrued interest receivable	-265	-2,809	-4,715
Net decrease (increase) in other assets	19,881	-3,286	12,464
Net decrease in accrued interest payable	-1,354	-1,150	-1,420
Net (decrease) increase in other liabilities	-9,097	11,303	4,216
Net cash provided by operating activities	334,095	183,793	186,843
Investing Activities	'	'	'
Proceeds from sales, maturities and prepayments of investment securities, available-for-sale	1,864,334	2,041,416	1,024,508
Purchases of investment securities, available-for-sale	-1,426,262	-2,638,054	-1,730,244
Principal collected on loans	1,224,222	1,034,374	958,401
Loans originated or acquired	-1,559,353	-1,049,344	-826,329
Net addition of premises and equipment and other real estate owned	-8,977	-10,730	-17,492
Proceeds from sale of other real estate owned	28,535	41,804	46,703
Net sale of non-marketable equity securities	583	888	15,357
Net cash received from acquisitions	26,155	0	0
Net cash provided by (used in) investment activities	149,237	-579,646	-529,096
Financing Activities	'	'	'
Net (decrease) increase in deposits	-334,672	543,248	299,311
Net increase in securities sold under agreements to repurchase	23,886	30,865	9,240
Net (decrease) increase in Federal Home Loan Bank advances	-162,298	-72,033	103,905
Net (decrease) increase in federal funds purchased and other borrowed funds	-1,502	180	-9,867
Cash dividends paid	-44,232	-47,472	-37,395
Excess tax deficiencies from stock-based compensation	-223	-8	0
Proceeds from stock options exercised	4,326	81	0
Net cash (used in) provided by financing activities	-514,715	454,861	365,194
Net (decrease) increase in cash and cash equivalents	-31,383	59,008	22,941
Cash and cash equivalents at beginning of period	187,040	128,032	105,091
Cash and cash equivalents at end of period	155,657	187,040	128,032
Supplemental Disclosure of Cash Flow Information	'	'	'
Cash paid during the period for interest	30,111	36,865	45,913
Cash paid during the period for income taxes	23,576	21,257	7,925
Supplemental Disclosure of Non-Cash Investing Activities	'	'	'
Sale and refinancing of other real estate owned	4,819	5,659	8,665
Transfer of loans to other real estate owned	15,266	27,536	79,295
Fair value of common stock shares issued	45,033	0	0
Cash consideration for outstanding shares	24,858	0	0
Fair value of assets acquired	630,569	0	0
Liabilities assumed	$560,678	$0	$0

Nature_of_Operations_and_Summa

Nature of Operations and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Nature of Operations and Summary of Significant Accounting Policies	'
	Note 1. Nature of Operations and Summary of Significant Accounting Policies
	General
	Glacier Bancorp, Inc. (“Company”) is a Montana corporation headquartered in Kalispell, Montana. The Company provides a full range of banking services to individual and corporate customers in Montana, Idaho, Wyoming, Colorado, Utah and Washington through thirteen divisions of its wholly-owned bank subsidiary, Glacier Bank (“Bank”). The Company offers a wide range of banking products and services, including transaction and savings deposits, real estate, commercial, agriculture and consumer loans and mortgage origination services. The Company serves individuals, small to medium-sized businesses, community organizations and public entities.
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates.
	Material estimates that are particularly susceptible to significant change include: 1) the determination of the allowance for loan and lease losses (“ALLL” or “allowance”), 2) the valuations related to investments and real estate acquired in connection with foreclosures or in satisfaction of loans, and 3) the evaluation of goodwill impairment. For the determination of the ALLL and real estate valuation estimates, management obtains independent appraisals (new or updated) for significant items. Estimates relating to investment valuations are obtained from independent third parties. Estimates relating to the evaluation of goodwill for impairment are determined based on internal calculations using significant independent party inputs.
	Principles of Consolidation
	The consolidated financial statements of the Company include the parent holding company and the Bank. The Bank consists of thirteen bank divisions, a treasury division and an information technology division. The treasury division was formed on January 1, 2013 to efficiently manage the Bank’s investment security portfolio and wholesale borrowings. The information technology division was formed on January 1, 2013 and includes the Bank’s internal data processing and information technology expenses that previously were included with the parent holding company. Each of the bank divisions operate under separate names, management teams and directors. The Company considers the Bank to be its sole operating segment as the Bank 1) engages in similar bank business activity from which it earns revenues and incurs expenses, 2) the operating results of the Bank are regularly reviewed by the Chief Executive Officer (i.e., the chief operating decision maker) who makes decisions about resources to be allocated to the Bank, and 3) financial information is available for the Bank. All significant inter-company transactions have been eliminated in consolidation.
	On May 31, 2013, the Company completed its acquisition of Wheatland Bankshares, Inc. (“Wheatland”) and its wholly-owned subsidiary, First State Bank, a community bank based in Wheatland, Wyoming. On July 31, 2013, the Company completed its acquisition of North Cascades Bancshares, Inc. (“NCBI”) and its wholly-owned subsidiary, North Cascades National Bank, a community bank based in Chelan, Washington. Both transactions were accounted for using the acquisition method, and their results of operations have been included in the Company’s consolidated financial statements as of the acquisition dates.
	The Company formed GBCI Other Real Estate (“GORE”) to isolate certain bank foreclosed properties for legal protection and administrative purposes and the remaining properties are currently held for sale. GORE is included in the Bank operating segment due to its insignificant activity.
	The Company owns the following trust subsidiaries, each of which issued trust preferred securities as Tier 1 capital instruments: Glacier Capital Trust II, Glacier Capital Trust III, Glacier Capital Trust IV, Citizens (ID) Statutory Trust I, Bank of the San Juans Bancorporation Trust I, First Company Statutory Trust 2001 and First Company Statutory Trust 2003. The trust subsidiaries are not included in the Company’s consolidated financial statements.
	Variable Interest Entities
	A variable interest entity (“VIE”) exists when either 1) the entity’s total equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support from other parties, or 2) the entity has equity investors that cannot make significant decisions about the entity’s operations or that do not absorb their proportionate share of the expected losses or receive the expected returns of the entity. In addition, a VIE must be consolidated by the Company if it is deemed to be the primary beneficiary of the VIE, which is the party involved with the VIE that has the power to direct the VIE’s significant activities and will absorb a majority of the expected losses, receive a majority of the expected residual returns, or both. The Company’s VIEs are regularly monitored to determine if any reconsideration events have occurred that could cause the primary beneficiary status to change.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	The Company has equity investments in Certified Development Entities (“CDE”) which have received allocations of New Markets Tax Credits (“NMTC”). The Company also has equity investments in Low-Income Housing Tax Credit (“LIHTC”) partnerships. The CDEs and the LIHTC partnerships are VIEs. The underlying activities of the VIEs are community development projects designed primarily to promote community welfare, such as economic rehabilitation and development of low-income areas by providing housing, services, or jobs for residents. The maximum exposure to loss in the VIEs is the amount of equity invested and credit extended by the Company. However, the Company has credit protection in the form of indemnification agreements, guarantees, and collateral arrangements. The primary activities of the VIEs are recognized in commercial loans interest income, other non-interest income and other borrowed funds interest expense on the Company’s statements of operations. Such related cash flows are recognized in loans originated, principal collected on loans and change in other borrowed funds. The Company has evaluated the variable interests held by the Company in each CDE (NMTC) and LIHTC partnership investment and determined that the Company continues to be the primary beneficiary of such VIEs. As the primary beneficiary, the VIEs’ assets, liabilities, and results of operations are included in the Company’s consolidated financial statements.
	The following table summarizes the carrying amounts of the VIEs’ assets and liabilities included in the Company’s consolidated financial statements at December 31, 2013 and 2012:
		31-Dec-13			31-Dec-12
	(Dollars in thousands)	CDE (NMTC)		LIHTC	CDE (NMTC)	LIHTC
	Assets
	Loans receivable	$	36,039	—	35,480	—
	Premises and equipment, net	—		13,536	—	16,066
	Accrued interest receivable	117		—	117	—
	Other assets	843		153	1,114	143
	Total assets	$	36,999	13,689	36,711	16,209
	Liabilities
	Other borrowed funds	$	4,555	1,723	4,555	3,639
	Accrued interest payable	4		5	4	6
	Other liabilities	151		189	182	136
	Total liabilities	$	4,710	1,917	4,741	3,781
	Amounts presented in the table above are adjusted for intercompany eliminations. All assets presented can be used only to settle obligations of the consolidated VIEs and all liabilities presented consist of liabilities for which creditors and other beneficial interest holders therein have no recourse to the general credit of the Company.
	Cash and Cash Equivalents
	Cash and cash equivalents include cash on hand, cash held as demand deposits at various banks and regulatory agencies, interest bearing deposits, federal funds sold and liquid investments with original maturities of three months or less.
	Investment Securities
	Debt securities for which the Company has the positive intent and ability to hold to maturity are classified as held-to-maturity (“HTM”) and are carried at amortized cost. Debt and equity securities held primarily for the purpose of selling in the near term are classified as trading securities and are reported at fair market value, with unrealized gains and losses included in income. Debt and equity securities not classified as HTM or trading are classified as available-for-sale (“AFS”) and are reported at fair value with unrealized gains and losses, net of income taxes, as a separate component of other comprehensive income. Premiums and discounts on investment securities are amortized or accreted into income using a method that approximates the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	The Company reviews and analyzes the various risks that may be present within the investment securities portfolio on an ongoing basis, including market risk and credit risk. Market risk is the risk to an entity’s financial condition resulting from adverse changes in the value of its holdings arising from movements in interest rates, foreign exchange rates, equity prices or commodity prices. The Company assesses the market risk of individual securities as well as the investment securities portfolio as a whole. Credit risk, broadly defined, is the risk that an issuer or counterparty will fail to perform on an obligation. A security is investment grade if the issuer has an adequate capacity to meet its commitment over the expected life of the investment, i.e., the risk of default is low and full and timely repayment of interest and principal is expected. To determine investment grade status for securities, the Company conducts due diligence of the creditworthiness of the issuer or counterparty prior to acquisition and ongoing thereafter consistent with the risk characteristics of the security and the overall risk of the investment securities portfolio. Credit quality due diligence takes into account the extent to which a security is guaranteed by the U.S. government and other agencies of the U.S. government. The depth of the due diligence is based on the complexity of the structure, the size of the security, and takes into account material positions and specific groups of securities or stratifications for analysis and review of similar risk positions. The due diligence includes consideration of payment performance, collateral adequacy, internal analyses, third party research and analytics, external credit ratings and default statistics.
	For additional information relating to investment securities, see Note 3.
	Temporary versus Other-Than-Temporary Impairment
	The Company assesses individual securities in its investment securities portfolio for impairment at least on a quarterly basis, and more frequently when economic or market conditions warrant. An investment is impaired if the fair value of the security is less than its carrying value at the financial statement date. If impairment is determined to be other-than-temporary, an impairment loss is recognized by reducing the amortized cost for the credit loss portion of the impairment with a corresponding charge to earnings for a like amount.
	For fair value estimates provided by third party vendors, management also considered the models and methodology for appropriate consideration of both observable and unobservable inputs, including appropriately adjusted discount rates and credit spreads for securities with limited or inactive markets, and whether the quoted prices reflect orderly transactions. For certain securities, the Company obtained independent estimates of inputs, including cash flows, in supplement to third party vendor provided information. The Company also reviewed financial statements of select issuers, with follow up discussions with issuers’ management for clarification and verification of information relevant to the Company’s impairment analysis.
	In evaluating impaired securities for other-than-temporary impairment losses, management considers 1) the severity and duration of the impairment, 2) the credit ratings of the security, 3) the overall deal structure, including the Company’s position within the structure, the overall and near term financial performance of the issuer and underlying collateral, delinquencies, defaults, loss severities, recoveries, prepayments, cumulative loss projections, discounted cash flows and fair value estimates.
	In evaluating debt securities for other-than-temporary impairment losses, management assesses whether the Company intends to sell the security or if it is more-likely-than-not that the Company will be required to sell the debt security. In so doing, management considers contractual constraints, liquidity, capital, asset / liability management and securities portfolio objectives. If impairment is determined to be other-than-temporary and the Company does not intend to sell a debt security, and it is more-likely-than-not the Company will not be required to sell the security before recovery of its cost basis, it recognizes the credit component of an other-than-temporary impairment of a debt security in earnings and the remaining portion (noncredit portion) in other comprehensive income, net of tax. For held-to-maturity debt securities, the amount of an other-than-temporary impairment recorded in other comprehensive income for the noncredit portion of a previous other-than-temporary impairment is amortized prospectively, as an increase to the carrying amount of the security, over the remaining life of the security on the basis of the timing of future estimated cash flows of the security.
	If impairment is determined to be other-than-temporary and the Company intends to sell a debt security or it is more-likely-than-not the Company will be required to sell the security before recovery of its cost basis, it recognizes the entire amount of the other-than-temporary impairment in earnings.
	For debt securities with other-than-temporary impairment, the previous amortized cost basis less the other-than-temporary impairment recognized in earnings shall be the new amortized cost basis of the security. In subsequent periods, the Company accretes into interest income the difference between the new amortized cost basis and cash flows expected to be collected prospectively over the life of the debt security.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	Loans Held for Sale
	Loans held for sale generally consist of long-term, fixed rate, conforming, single-family residential real estate loans and are carried at the lower of cost or estimated fair value in the aggregate. Net unrealized losses, if any, are recognized by charges to non-interest income. A sale is recognized when the Company surrenders control of the loan and consideration, is received in exchange. A gain is recognized in non-interest income to the extent the sales price exceeds the carrying value of the sold loan.
	Loans Receivable
	Loans that are intended to be held-to-maturity are reported at the unpaid principal balance less net charge-offs and adjusted for deferred fees and costs on originated loans and unamortized premiums or discounts on acquired loans. Fees and costs on originated loans and premiums or discounts on acquired loans are deferred and subsequently amortized or accreted as a yield adjustment over the expected life of the loan utilizing the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. When a loan is paid off prior to maturity, the remaining fees and costs on originated loans and premiums or discounts on acquired loans are immediately recognized into interest income.
	The Company’s loan segments, which are based on the purpose of the loan, include residential real estate, commercial, and consumer loans. The Company’s loan classes, a further disaggregation of segments, include residential real estate loans (residential real estate segment), commercial real estate and other commercial loans (commercial segment), and home equity and other consumer loans (consumer segment).
	Loans that are thirty days or more past due based on payments received and applied to the loan are considered delinquent. Loans are designated non-accrual and the accrual of interest is discontinued when the collection of the contractual principal or interest is unlikely. A loan is typically placed on non-accrual when principal or interest is due and has remained unpaid for ninety days or more. When a loan is placed on non-accrual status, interest previously accrued but not collected is reversed against current period interest income. Subsequent payments on non-accrual loans are applied to the outstanding principal balance if doubt remains as to the ultimate collectability of the loan. Interest accruals are not resumed on partially charged-off impaired loans. For other loans on nonaccrual, interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of management, the loans are estimated to be fully collectible as to both principal and interest.
	The Company considers impaired loans to be the primary credit quality indicator for monitoring the credit quality of the loan portfolio. Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. Impaired loans include non-performing loans (i.e., non-accrual loans and accruing loans ninety days or more past due) and accruing loans under ninety days past due where it is probable payments will not be received according to the loan agreement (e.g., troubled debt restructuring). Interest income on accruing impaired loans is recognized using the interest method. The Company measures impairment on a loan-by-loan basis in the same manner for each class within the loan portfolio. An insignificant delay or shortfall in the amounts of payments would not cause a loan or lease to be considered impaired. The Company determines the significance of payment delays and shortfalls on a case-by-case basis, taking into consideration all of the facts and circumstances surrounding the loan and the borrower, including the length and reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest due.
	A restructured loan is considered a troubled debt restructuring (“TDR”) if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. A TDR loan is considered an impaired loan and a specific valuation allowance is established when the fair value of the collateral-dependent loan or present value of the loan’s expected future cash flows (discounted at the loan’s effective interest rate based on the original contractual rate) is lower than the carrying value of the impaired loan. The Company has made the following types of loan modifications, some of which were considered a TDR:
	•	Reduction of the stated interest rate for the remaining term of the debt;
	•	Extension of the maturity date(s) at a stated rate of interest lower than the current market rate for newly originated debt having similar risk characteristics; and
	•	Reduction of the face amount of the debt as stated in the debt agreements.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	The Company recognizes that while borrowers may experience deterioration in their financial condition, many continue to be creditworthy customers who have the willingness and capacity for debt repayment. In determining whether non-restructured or unimpaired loans issued to a single or related party group of borrowers should continue to accrue interest when the borrower has other loans that are impaired or are TDRs, the Company on a quarterly or more frequent basis performs an updated and comprehensive assessment of the willingness and capacity of the borrowers to timely and ultimately repay their total debt obligations, including contingent obligations. Such analysis takes into account current financial information about the borrowers and financially responsible guarantors, if any, including for example:
	•	analysis of global, i.e., aggregate debt service for total debt obligations;
	•	assessment of the value and security protection of collateral pledged using current market conditions and alternative market assumptions across a variety of potential future situations; and
	•	loan structures and related covenants.
	For additional information relating to loans, see Note 4.
	Allowance for Loan and Lease Losses
	Based upon management’s analysis of the Company’s loan portfolio, the balance of the ALLL is an estimate of probable credit losses known and inherent within the Bank’s loan portfolio as of the date of the consolidated financial statements. The ALLL is analyzed at the loan class level and is maintained within a range of estimated losses. Determining the adequacy of the ALLL involves a high degree of judgment and is inevitably imprecise as the risk of loss is difficult to quantify. The determination of the ALLL and the related provision for loan losses is a critical accounting estimate that involves management’s judgments about all known relevant internal and external environmental factors that affect loan losses. The balance of the ALLL is highly dependent upon management’s evaluations of borrowers’ current and prospective performance, appraisals and other variables affecting the quality of the loan portfolio. Individually significant loans and major lending areas are reviewed periodically to determine potential problems at an early date. Changes in management’s estimates and assumptions are reasonably possible and may have a material impact upon the Company’s consolidated financial statements, results of operations or capital.
Risk characteristics considered in the ALLL analysis applicable to each loan class within the Company's loan portfolio are as follows:
Residential Real Estate.  Residential real estate loans are secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class include a large number of borrowers, geographic dispersion of market areas and the loans are originated for relatively smaller amounts.
Commercial Real Estate.  Commercial real estate loans typically involve larger principal amounts, and repayment of these loans is generally dependent on the successful operation of the property securing the loan and / or the business conducted on the property securing the loan.  Credit risk in these loans is impacted by the creditworthiness of a borrower, valuation of the property securing the loan and conditions within the local economies in the Company’s diverse, geographic market areas.
Commercial.  Commercial loans consist of loans to commercial customers for use in financing working capital needs, equipment purchases and business expansions.  The loans in this category are repaid primarily from the cash flow of a borrower’s principal business operation.  Credit risk in these loans is driven by creditworthiness of a borrower and the economic conditions that impact the cash flow stability from business operations across the Company’s diverse, geographic market areas.
Home Equity.  Home equity loans consist of junior lien mortgages and first and junior lien lines of credit (revolving open-end and amortizing closed-end) secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the residential property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class are a large number of borrowers, geographic dispersion of market areas and the loans are originated for terms that range from 10 years to 15 years.
Other Consumer.  The other consumer loan portfolio consists of various short-term loans such as automobile loans and loans for other personal purposes.  Repayment of these loans is primarily dependent on the personal income of the borrowers.  Credit risk is driven by consumer economic factors (such as unemployment and general economic conditions in the Company’s diverse, geographic market area) and the creditworthiness of a borrower.
Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
The ALLL consists of a specific valuation allowance component and a general valuation allowance component. The specific component relates to loans that are determined to be impaired and individually evaluated for impairment. The Company measures impairment on a loan-by-loan basis based on the present value of expected future cash flows discounted at the loan’s effective interest rate, except when it is determined that repayment of the loan is expected to be provided solely by the underlying collateral. For impairment based on expected future cash flows, the Company considers all information available as of a measurement date, including past events, current conditions, potential prepayments, and estimated cost to sell when such costs are expected to reduce the cash flows available to repay or otherwise satisfy the loan. For alternative ranges of cash flows, the likelihood of the possible outcomes is considered in determining the best estimate of expected future cash flows. The effective interest rate for a loan restructured in a TDR is based on the original contractual rate. For collateral-dependent loans and real estate loans for which foreclosure or a deed-in-lieu of foreclosure is probable, impairment is measured by the fair value of the collateral, less estimated cost to sell. The fair value of the collateral is determined primarily based upon appraisal or evaluation of the underlying real property value.
The general valuation allowance component relates to probable credit losses inherent in the balance of the loan portfolio based on historical loss experience, adjusted for changes in trends and conditions of qualitative or environmental factors. The historical loss experience is based on the previous twelve quarters loss experience by loan class adjusted for risk characteristics in the existing loan portfolio. The same trends and conditions are evaluated for each class within the loan portfolio; however, the risk characteristics are weighted separately at the individual class level based on the Company’s judgment and experience.
The changes in trends and conditions of certain items include the following:
•	Changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses;
•	Changes in international, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments;
•	Changes in the nature and volume of the portfolio and in the terms of loans;
•	Changes in experience, ability, and depth of lending management and other relevant staff;
•	Changes in the volume and severity of past due and nonaccrual loans;
•	Changes in the quality of the Company’s loan review system;
•	Changes in the value of underlying collateral for collateral-dependent loans;
•	The existence and effect of any concentrations of credit, and changes in the level of such concentrations; and
•	The effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the Company’s existing portfolio.
The ALLL is increased by provisions for loan losses which are charged to expense. The portions of loan balances determined by management to be uncollectible are charged-off as a reduction of the ALLL and recoveries of amounts previously charged-off are credited as an increase to the ALLL. The Company’s charge-off policy is consistent with bank regulatory standards. Consumer loans generally are charged off when the loan becomes over 120 days delinquent. Real estate acquired as a result of foreclosure or by deed-in-lieu of foreclosure is classified as real estate owned until such time as it is sold.
At acquisition date, the assets and liabilities of acquired banks are recorded at their estimated fair values which results in no ALLL carried over from acquired banks. Subsequent to acquisition, an allowance will be recorded on the acquired loan portfolios for further credit deterioration, if any.
Premises and Equipment
Premises and equipment are accounted for at cost less depreciation. Depreciation is computed on a straight-line method over the estimated useful lives or the term of the related lease. The estimated useful life for office buildings is 15 - 40 years and the estimated useful life for furniture, fixtures, and equipment is 3 - 10 years. Interest is capitalized for any significant building projects. For additional information relating to premises and equipment, see Note 5.
Leases
The Company leases certain land, premises and equipment from third parties under operating and capital leases. The lease payments for operating lease agreements are recognized on a straight-line basis. The present value of the future minimum rental payments for capital leases is recognized as an asset when the lease is formed. Lease improvements incurred at the inception of the lease are recorded as an asset and depreciated over the initial term of the lease and lease improvements incurred subsequently are depreciated over the remaining term of the lease. For additional information relating to leases, see Note 5.
Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
Other Real Estate Owned
Property acquired by foreclosure or deed-in-lieu of foreclosure is initially recorded at fair value, less estimated selling cost, at acquisition date (i.e., cost of the property). Fair value is determined as the amount that could be reasonably expected in a current sale between a willing buyer and a willing seller in an orderly transaction between market participants at the measurement date. Subsequent to the initial acquisition, if the fair value of the asset, less estimated selling cost, is less than the cost of the property, a loss is recognized in other expense and the asset carrying value is reduced. Gain or loss on disposition of other real estate owned (“OREO”) is recorded in non-interest income or non-interest expense, respectively. In determining the fair value of the properties on the date of transfer and any subsequent estimated losses of net realizable value, the fair value of other real estate acquired by foreclosure or deed-in-lieu of foreclosure is determined primarily based upon appraisal or evaluation of the underlying property value.
Long-lived Assets
Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. An asset is deemed impaired if the sum of the expected future cash flows is less than the carrying amount of the asset. If impaired, an impairment loss is recognized in other expense to reduce the carrying value of the asset to fair value. At December 31, 2013 and 2012, no long-lived assets were considered impaired.
Business Combinations and Intangible Assets
Acquisition accounting requires the total purchase price to be allocated to the estimated fair values of assets acquired and liabilities assumed, including certain intangible assets. Goodwill is recorded if the purchase price exceeds the net fair value of assets acquired and a bargain purchase gain is recorded in other income if the net fair value of assets acquired exceeds the purchase price.
Adjustment of the allocated purchase price may be related to fair value estimates for which all information has not been obtained of the acquired entity known or discovered during the allocation period, the period of time required to identify and measure the fair values of the assets and liabilities acquired in the business combination. The allocation period is generally limited to one year following consummation of a business combination.
Core deposit intangible represents the intangible value of depositor relationships resulting from deposit liabilities assumed in acquisitions and is amortized using an accelerated method based on an estimated runoff of the related deposits. The core deposit intangible is evaluated for impairment and recoverability whenever events or changes in circumstances indicate that its carrying amount may not be recoverable, with any changes in estimated useful life accounted for prospectively over the revised remaining life. For additional information relating to core deposit intangibles, see Note 6.
The Company tests goodwill for impairment at the reporting unit level annually during the third quarter. The Company has identified that each of the bank divisions are reporting units (i.e., components of the Glacier Bank operating segment) given that each division has a separate management team that regularly reviews its respective division financial information; however, the reporting units are aggregated into a single reporting unit due to the reporting units having similar economic characteristics.
The goodwill of a reporting unit is tested for impairment between annual tests if an event occurs or circumstances change that would more-likely-than not reduce the fair value of a reporting units below its carrying amount. Examples of events and circumstances that could trigger the need for interim impairment testing include:
•	A significant change in legal factors or in the business climate;
•	An adverse action or assessment by a regulator;
•	Unanticipated competition;
•	A loss of key personnel;
•	A more-likely-than-not expectation that a reporting unit or a significant portion of a reporting unit will be sold or otherwise disposed of; and
•	The testing for recoverability of a significant asset group within a reporting unit.
Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
For the goodwill impairment assessment, the Company has the option, prior to the two-step process, to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of a reporting unit is less than its carrying value. The Company opted to bypass the qualitative assessment for its 2013 and 2012 annual goodwill impairment testing and proceed directly to the two-step goodwill impairment test. The goodwill impairment two-step process requires the Company to make assumptions and judgments regarding fair value. In the first step, the Company calculates an implied fair value based on a control premium analysis. If the implied fair value is less than the carrying value, the second step is completed to compute the impairment amount, if any, by determining the “implied fair value” of goodwill. This determination requires the allocation of the estimated fair value of the reporting units to the assets and liabilities of the reporting units. Any remaining unallocated fair value represents the “implied fair value” of goodwill, which is compared to the corresponding carrying value of goodwill to compute impairment, if any.
For additional information relating to goodwill, see Note 6.
Non-Marketable Equity Securities
Non-marketable equity securities primarily consists of Federal Home Loan Bank (“FHLB”) stock. FHLB stock is restricted because such stock may only be sold to FHLB at its par value. Due to restrictive terms, and the lack of a readily determinable market value, FHLB stock is carried at cost. The investments in FHLB stock are required investments related to the Company’s borrowings from FHLB. FHLB obtains its funding primarily through issuance of consolidated obligations of the FHLB system. The U.S. government does not guarantee these obligations, and each of the regional FHLBs are jointly and severally liable for repayment of each other’s debt.
Derivatives and Hedging Activities
For asset and liability management purposes, the Company has entered into interest rate swap agreements to hedge against changes in forecasted cash flows due to interest rate exposures. The interest rate swaps are recognized as assets or liabilities on the Company’s statements of financial condition and measured at fair value. Fair value estimates are obtained from third parties and are based on pricing models. The Company does not enter into interest rate swap agreements for trading or speculative purposes.
The Company takes into account the impact of bilateral collateral and master netting agreements that allows the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset the net interest rate swap derivative position with the related collateral when recognizing interest rate swap derivative assets and liabilities.
Interest rate swaps are contracts in which a series of interest payments are exchanged over a prescribed period. The notional amount upon which the interest payments are based is not exchanged. The swap agreements are derivative instruments and convert a portion of the Company’s forecasted variable rate debt to a fixed rate (i.e., cash flow hedge). The effective portion of the gain or loss on the cash flow hedging instruments is initially reported as a component of other comprehensive income and subsequently reclassified into earnings in the same period during which the transaction affects earnings. The ineffective portion of the gain or loss on derivative instruments, if any, is recognized in earnings. The Company currently has cash flow hedges of which no portion is ineffective.
Interest rate derivative financial instruments receive hedge accounting treatment only if they are designated as a hedge and are expected to be, and are, effective in substantially reducing interest rate risk arising from the assets and liabilities identified as exposing the Company to risk. Derivative financial instruments that do not meet specified hedging criteria are recorded at fair value with changes in fair value recorded in income. The Company’s interest rate swaps are considered highly effective and currently meet the hedging accounting criteria.
Cash flows resulting from the interest rate derivative financial instruments that are accounted for as hedges of assets and liabilities are classified in the Company’s cash flow statement in the same category as the cash flows of the items being hedged. For additional information relating to interest rate swap agreements, see Note 11.
Comprehensive Income
Comprehensive income consists of net income and other comprehensive income. Other comprehensive income includes unrealized gains and losses, net of tax effect, on available-for-sale securities and unrealized gains and losses, net of tax effect, on derivatives used for cash flow hedges.
Advertising and Promotion
Advertising and promotion costs are recognized in the period incurred.
Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
Income Taxes
The Company’s income tax expense consists of current and deferred income tax expense. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of enacted tax law to earnings or losses. Deferred income tax expense results from changes in deferred assets and liabilities between periods.
Deferred tax assets and liabilities are recognized for estimated future income tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases. The effect on deferred tax assets and liabilities of a change in income tax rates is recognized in income in the period that includes the enactment date.
Deferred tax assets are reduced by a valuation allowance, if based on the weight of available evidence, it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The term more-likely-than-not means a likelihood of more than fifty percent. The recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to the Company’s judgment. In assessing the need for a valuation allowance, the Company considers both positive and negative evidence. For additional information relating to income taxes, see Note 14.
Earnings Per Share
Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding stock options were exercised, using the treasury stock method. For additional information relating to earnings per share, see Note 15.
Stock-based Compensation
Stock-based compensation awards granted, comprised of stock options and restricted stock awards, are valued at fair value and compensation cost is recognized on a straight-line basis, net of estimated forfeitures, over the requisite service period of each award. For additional information relating to stock-based compensation, see Note 17.
Reclassifications
Certain reclassifications have been made to the 2012 and 2011 financial statements to conform to the 2013 presentation.
Impact of Recent Authoritative Accounting Guidance
The Accounting Standards Codification™ (“ASC”) is the Financial Accounting Standards Board’s (“FASB”) officially recognized source of authoritative GAAP applicable to all public and non-public non-governmental entities. Rules and interpretive releases of the Securities and Exchange Commission (“SEC”) under the authority of the federal securities laws are also sources of authoritative GAAP for the Company as an SEC registrant. All other accounting literature is non-authoritative.
In January 2014, FASB amended FASB ASC Subtopic 310-40, Receivables - Troubled Debt Restructurings by Creditors. The amendment clarifies that an in substance repossession foreclosure occurs when a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either 1) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or 2) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. Additionally, the amendment requires interim and annual disclosure of both 1) the amount of foreclosed residential real estate property held by the creditor and 2) the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure according to local requirements of the applicable jurisdiction. The amendment is effective for public business entities for interim and annual periods beginning after December 15, 2014. An entity can elect to adopt the amendments using either a modified retrospective transition method or a prospective transition method as defined in the amendment. The Company is currently evaluating the impact of the adoption of this amendment, but does not expect it to have a material effect on the Company’s financial position or results of operations.
In January 2014, FASB amended FASB ASC Topic 323, Investments - Equity Method and Joint Ventures. The amendments permit entities to make an accounting policy election for their investments in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportional amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense. The amendments should be applied retrospectively to all periods presented and are effective for public business entities for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The Company is currently evaluating the impact of the adoption of the amendments, but does not expect them to have a material effect on the Company’s financial position or results of operations.
Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
In June 2011, FASB amended FASB ASC Topic 220, Comprehensive Income. The amendment provides an entity the option to present the total of comprehensive income, the components of net income, and the components of other comprehensive income either in a single continuous statement or in two separate but consecutive statements. Accounting Standards Update (“ASU”) No. 2011-12, Comprehensive Income (Topic 220) deferred the specific requirement of the amendment to present items that are reclassified from accumulated other comprehensive income to net income separately with their respective components of net income and other comprehensive income. The amendments were effective retrospectively during interim and annual periods beginning after December 15, 2011. ASU No. 2013-2, Comprehensive Income (Topic 220) reversed the deferment of ASU 2011-12 and will be effective prospectively for reporting periods beginning after December 15, 2012 and early adoption is permitted. The Company early adopted ASU No. 2013-2 as of December 31, 2012. The Company has evaluated the impact of the adoption of these amendments and determined there was not a material effect on the Company’s financial position or results of operations.

Cash_on_Hand_and_in_Banks

Cash on Hand and in Banks	12 Months Ended
	Dec. 31, 2013
Cash and Cash Equivalents [Abstract]	'
Cash on Hand and in Banks	'
	Note 2. Cash on Hand and in Banks
	At December 31, 2013 and 2012, cash on hand and in banks primarily consisted of cash on hand and cash items in process. The Bank is required to maintain an average reserve balance with either the Federal Reserve Bank (“FRB”) or in the form of cash on hand. The required reserve balance at December 31, 2013 was $20,011,000.

Investment_Securities_Availabl

Investment Securities, Available-for-Sale	12 Months Ended
	Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]	'
Investment Securities, Available-for-Sale	'
	Note 3. Investment Securities, Available-for-Sale
	A comparison of the amortized cost and estimated fair value of the Company’s investment securities designated as available-for-sale is presented below.
		31-Dec-13
		Weighted			Amortized			Gross Unrealized				Fair
	(Dollars in thousands)	Yield			Cost			Gains		Losses		Value
	U.S. government sponsored enterprises
	Maturing after one year through five years	2.32	%		$	10,405		187		—		10,592
	Maturing after five years through ten years	2	%		36			—		—		36
		2.32	%		10,441			187		—		10,628
	State and local governments
	Maturing within one year	2.22	%		5,964			57		—		6,021
	Maturing after one year through five years	2.06	%		174,826			3,486		(448	)	177,864
	Maturing after five years through ten years	3.21	%		58,835			831		(1,040	)	58,626
	Maturing after ten years	4.41	%		1,137,722			27,247		(22,402	)	1,142,567
		4.06	%		1,377,347			31,621		(23,890	)	1,385,078
	Corporate bonds
	Maturing within one year	2.17	%		91,687			719		—		92,406
	Maturing after one year through five years	2.09	%		341,799			3,203		(1,676	)	343,326
	Maturing after five years through ten years	2.23	%		6,851			—		(82	)	6,769
		2.11	%		440,337			3,922		(1,758	)	442,501
	Residential mortgage-backed securities	2.48	%		1,380,816			14,071		(10,265	)	1,384,622
	Total investment securities	3.1	%		$	3,208,941		49,801		(35,913	)	3,222,829
	Note 3. Investment Securities, Available-for-Sale (continued)
		31-Dec-12
		Weighted			Amortized			Gross Unrealized				Fair
	(Dollars in thousands)	Yield			Cost			Gains		Losses		Value
	U.S. government and federal agency
	Maturing within one year	1.62	%		$	201		1		—		202
	U.S. government sponsored enterprises
	Maturing after one year through five years	2.3	%		17,064			371		—		17,435
	Maturing after five years through ten years	2.03	%		44			1		—		45
		2.29	%		17,108			372		—		17,480
	State and local governments
	Maturing within one year	2.01	%		4,288			28		(2	)	4,314
	Maturing after one year through five years	2.11	%		149,497			4,142		(142	)	153,497
	Maturing after five years through ten years	2.95	%		38,346			1,102		(99	)	39,349
	Maturing after ten years	4.7	%		935,897			82,823		(1,362	)	1,017,358
		4.29	%		1,128,028			88,095		(1,605	)	1,214,518
	Corporate bonds
	Maturing within one year	1.73	%		18,412			51		—		18,463
	Maturing after one year through five years	2.22	%		250,027			4,018		(238	)	253,807
	Maturing after five years through ten years	2.23	%		16,144			381		—		16,525
		2.19	%		284,583			4,450		(238	)	288,795
	Collateralized debt obligations
	Maturing after ten years	8.03	%		1,708			—		—		1,708
	Residential mortgage-backed securities	1.95	%		2,156,049			8,860		(4,607	)	2,160,302
	Total investment securities	2.71	%		$	3,587,677		101,778		(6,450	)	3,683,005
	Included in the residential mortgage-backed securities are $2,602,000 and $46,733,000 as of December 31, 2013 and 2012, respectively, of non-guaranteed private label whole loan mortgage-backed securities of which none of the underlying collateral is considered “subprime.”
	Maturities of securities do not reflect repricing opportunities present in adjustable rate securities, nor do they reflect expected shorter maturities based upon early prepayment of principal. Weighted-average yields are based on the interest method taking into account premium amortization, discount accretion and mortgage-backed securities’ prepayment provisions. Weighted-average yields on tax-exempt investment securities exclude the federal income tax benefit.
	Effective January 1, 2014, the Company reclassified obligations of state and local government securities with a fair value of approximately $484,583,000, inclusive of a net unrealized gain of $4,624,000, from AFS classification to HTM classification. The reclassification changed the allocation of the Company’s entire investment securities portfolio from 100 percent AFS to approximately 85 percent AFS and 15 percent HTM.
	Note 3. Investment Securities, Available-for-Sale (continued)
	The cost of each investment sold is determined by specific identification. Gain or loss on sale of investments consists of the following:
		Years ended
	(Dollars in thousands)	December 31,				December 31,		December 31,
		2013				2012		2011
	Gross proceeds	$	181,971			—		18,916
	Less amortized cost	(182,270		)		—		(18,570	)
	Net (loss) gain on sale of investments	$	(299	)		—		346
	Gross gain on sale of investments	$	3,723			—		1,048
	Gross loss on sale of investments	(4,022		)		—		(702	)
	Net (loss) gain on sale of investments	$	(299	)		—		346
	At December 31, 2013 and 2012, the Company had investment securities with fair values of $1,635,316,000 and $1,525,400,000, respectively, pledged as collateral for FHLB advances, FRB discount window borrowings, securities sold under agreements to repurchase (“repurchase agreements”), interest rate swap agreements and deposits of several local government units.
	Investments with an unrealized loss position are summarized as follows:
	31-Dec-13
	Less than 12 Months						12 Months or More				Total
(Dollars in thousands)	Fair				Unrealized		Fair		Unrealized		Fair	Unrealized
	Value				Loss		Value		Loss		Value	Loss
U.S. government sponsored enterprises	$	3			—		—		—		3	—
State and local governments	408,812				(17,838	)	74,161		(6,052	)	482,973	(23,890	)
Corporate bonds	129,515				(1,672	)	1,702		(86	)	131,217	(1,758	)
Residential mortgage-backed securities	457,611				(10,226	)	1,993		(39	)	459,604	(10,265	)
Total temporarily impaired securities	$	995,941			(29,736	)	77,856		(6,177	)	1,073,797	(35,913	)
	31-Dec-12
	Less than 12 Months						12 Months or More				Total
(Dollars in thousands)	Fair				Unrealized		Fair		Unrealized		Fair	Unrealized
	Value				Loss		Value		Loss		Value	Loss
State and local governments	$	102,896			(1,531	)	4,533		(74	)	107,429	(1,605	)
Corporate bonds	41,856				(238	)	—		—		41,856	(238	)
Residential mortgage-backed securities	955,235				(4,041	)	62,905		(566	)	1,018,140	(4,607	)
Total temporarily impaired securities	$	1,099,987			(5,810	)	67,438		(640	)	1,167,425	(6,450	)
Based on an analysis of its investment securities with unrealized losses as of December 31, 2013 and 2012, the Company determined that none of such securities had other-than-temporary impairment and the unrealized losses were primarily the result of interest rate changes and market spreads subsequent to acquisition. The fair value of the debt securities is expected to recover as payments are received and the securities approach maturity. At December 31, 2013, management determined that it did not intend to sell investment securities with unrealized losses, and there was no expected requirement to sell any of its investment securities with unrealized losses before recovery of their amortized cost.

Loans_Receivable_Net

Loans Receivable, Net	12 Months Ended
	Dec. 31, 2013
Receivables [Abstract]	'
Loans Receivable, Net	'
	Note 4. Loans Receivable, Net
	The Company’s loan portfolio is comprised of three segments: residential real estate, commercial and consumer and other loans. The loan portfolio is managed at the class level which is comprised of the following classes: residential real estate, commercial real estate, other commercial, home equity and other consumer loans. The following tables are presented for each portfolio class of loans receivable and provide information about the ALLL, loans receivable, impaired loans and TDRs.
	The following schedules summarize the activity in the ALLL:
		Year ended December 31, 2013
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Balance at beginning of period	$	130,854		15,482		74,398		21,567		10,659		8,748
	Provision for loan losses	6,887			(921	)	(3,670	)	10,271		868		339
	Charge-offs	(13,643		)	(793	)	(3,736	)	(4,671	)	(2,594	)	(1,849	)
	Recoveries	6,253			299		3,340		1,463		366		785
	Balance at end of period	$	130,351		14,067		70,332		28,630		9,299		8,023
		Year ended December 31, 2012
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Balance at beginning of period	$	137,516		17,227		76,920		20,833		13,616		8,920
	Provision for loan losses	21,525			2,879		11,012		4,690		324		2,620
	Charge-offs	(34,672		)	(5,267	)	(16,339	)	(5,239	)	(4,369	)	(3,458	)
	Recoveries	6,485			643		2,805		1,283		1,088		666
	Balance at end of period	$	130,854		15,482		74,398		21,567		10,659		8,748
		Year ended December 31, 2011
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Balance at beginning of period	$	137,107		20,957		76,147		19,932		13,334		6,737
	Provision for loan losses	64,500			1,455		39,563		10,709		4,450		8,323
	Charge-offs	(69,366		)	(5,671	)	(42,042	)	(10,386	)	(4,644	)	(6,623	)
	Recoveries	5,275			486		3,252		578		476		483
	Balance at end of period	$	137,516		17,227		76,920		20,833		13,616		8,920
	Note 4. Loans Receivable, Net (continued)
	The following schedules disclose the ALLL and loans receivable:
		31-Dec-13
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Individually evaluated for impairment	$	11,949		990		3,763		6,155		265		776
	Collectively evaluated for impairment	118,402			13,077		66,569		22,475		9,034		7,247
	Total allowance for loan and lease losses	$	130,351		14,067		70,332		28,630		9,299		8,023
	Loans receivable
	Individually evaluated for impairment	$	199,680		24,070		119,526		41,504		9,039		5,541
	Collectively evaluated for impairment	3,863,158			553,519		1,929,721		810,532		357,426		211,960
	Total loans receivable	$	4,062,838		577,589		2,049,247		852,036		366,465		217,501
		31-Dec-12
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Individually evaluated for impairment	$	15,534		1,680		7,716		3,859		870		1,409
	Collectively evaluated for impairment	115,320			13,802		66,682		17,708		9,789		7,339
	Total allowance for loan and lease losses	$	130,854		15,482		74,398		21,567		10,659		8,748
	Loans receivable
	Individually evaluated for impairment	$	201,735		25,862		125,282		33,593		11,074		5,924
	Collectively evaluated for impairment	3,195,690			490,605		1,530,226		589,804		392,851		192,204
	Total loans receivable	$	3,397,425		516,467		1,655,508		623,397		403,925		198,128
	Substantially all of the Company’s loans receivable are with customers in the Company’s geographic market areas. Although the Company has a diversified loan portfolio, a substantial portion of its customers’ ability to honor their obligations is dependent upon the economic performance in the Company’s market areas. The Company is subject to regulatory limits for the amount of loans to any individual borrower and the Company is in compliance with this regulation as of December 31, 2013 and 2012. No borrower had outstanding loans or commitments exceeding 10 percent of the Company’s consolidated stockholders’ equity as of December 31, 2013.
	Net deferred fees, costs, premiums and discounts of $10,662,000 and $1,379,000 were included in the loans receivable balance at December 31, 2013 and 2012, respectively. The increase in net deferred fees, costs, premiums and discounts from the prior year was primarily due to the acquisitions of Wheatland and NCBI. For additional information relating to acquisitions, see Note 22. At December 31, 2013, the Company had $2,566,042,000 in variable rate loans and $1,496,796,000 in fixed rate loans. The weighted-average interest rate on loans was 5.04 percent and 5.33 percent at December 31, 2013 and 2012, respectively. At December 31, 2013, 2012, and 2011, loans sold and serviced for others were $148,376,000, $116,439,000, and $160,465,000, respectively. At December 31, 2013, the Company had loans of $2,579,874,000 pledged as collateral for FHLB advances and FRB discount window. There were no significant purchases or sales of loans designated held-to-maturity during 2013 and 2012.
	The Company has entered into transactions with its executive officers and directors and their affiliates. The aggregate amount of loans outstanding to such related parties at December 31, 2013 and 2012 was $35,224,000 and $33,869,000, respectively. During 2013, new loans to such related parties were $4,311,000 and repayments were $2,956,000. In management’s opinion, such loans were made in the ordinary course of business and were made on substantially the same terms as those prevailing at the time for comparable transaction with other persons.
	Note 4. Loans Receivable, Net (continued)
	The following schedules disclose the impaired loans:
		At or for the Year ended December 31, 2013
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Loans with a specific valuation allowance
Recorded balance	$	61,503		7,233		23,917		27,015		886		2,452
Unpaid principal balance	63,406			7,394		25,331		27,238		949		2,494
Specific valuation allowance	11,949			990		3,763		6,155		265		776
Average balance	59,823			7,237		26,105		22,460		767		3,254
Loans without a specific valuation allowance
Recorded balance	$	138,177		16,837		95,609		14,489		8,153		3,089
Unpaid principal balance	169,082			18,033		119,017		19,156		9,631		3,245
Average balance	139,129			18,103		95,808		14,106		8,844		2,268
Totals
Recorded balance	$	199,680		24,070		119,526		41,504		9,039		5,541
Unpaid principal balance	232,488			25,427		144,348		46,394		10,580		5,739
Specific valuation allowance	11,949			990		3,763		6,155		265		776
Average balance	198,952			25,340		121,913		36,566		9,611		5,522
	At or for the Year ended December 31, 2012
(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
				Real Estate		Real Estate		Commercial		Equity		Consumer
Loans with a specific valuation allowance
Recorded balance	$	62,759		7,334		29,595		21,205		1,354		3,271
Unpaid principal balance	70,261			7,459		36,887		21,278		1,362		3,275
Specific valuation allowance	15,534			1,680		7,716		3,859		870		1,409
Average balance	76,656			12,797		36,164		22,665		1,390		3,640
Loans without a specific valuation allowance
Recorded balance	$	138,976		18,528		95,687		12,388		9,720		2,653
Unpaid principal balance	149,412			19,613		102,798		14,318		9,965		2,718
Average balance	162,505			16,034		111,554		19,733		11,993		3,191
Totals
Recorded balance	$	201,735		25,862		125,282		33,593		11,074		5,924
Unpaid principal balance	219,673			27,072		139,685		35,596		11,327		5,993
Specific valuation allowance	15,534			1,680		7,716		3,859		870		1,409
Average balance	239,161			28,831		147,718		42,398		13,383		6,831
Interest income recognized on impaired loans for the years ended December 31, 2013, 2012, and 2011 was not significant.
Note 4. Loans Receivable, Net (continued)
The following is a loans receivable aging analysis:
	31-Dec-13
(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
				Real Estate		Real Estate		Commercial		Equity		Consumer
Accruing loans 30-59 days past due	$	25,761		10,367		7,016		3,673		2,432		2,273
Accruing loans 60-89 days past due	6,355			1,055		2,709		1,421		668		502
Accruing loans 90 days or more past due	604			429		—		160		5		10
Non-accrual loans	81,956			10,702		51,438		10,139		7,950		1,727
Total past due and non-accrual loans	114,676			22,553		61,163		15,393		11,055		4,512
Current loans receivable	3,948,162			555,036		1,988,084		836,643		355,410		212,989
Total loans receivable	$	4,062,838		577,589		2,049,247		852,036		366,465		217,501
	December 31, 2012
(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
				Real Estate		Real Estate		Commercial		Equity		Consumer
Accruing loans 30-59 days past due	$	17,454		3,897		7,424		2,020		2,872		1,241
Accruing loans 60-89 days past due	9,643			1,870		3,745		645		2,980		403
Accruing loans 90 days or more past due	1,479			451		594		197		188		49
Non-accrual loans	96,933			14,237		55,687		13,200		11,241		2,568
Total past due and non-accrual loans	125,509			20,455		67,450		16,062		17,281		4,261
Current loans receivable	3,271,916			496,012		1,588,058		607,335		386,644		193,867
Total loans receivable	$	3,397,425		516,467		1,655,508		623,397		403,925		198,128
Interest income that would have been recorded on non-accrual loans if such loans had been current for the entire period would have been approximately $4,122,000, $5,161,000, and $7,441,000 for the years ended December 31, 2013, 2012, and 2011, respectively.
The following is a summary of the TDRs that occurred during the periods presented and the TDRs that occurred within the previous twelve months that subsequently defaulted during the periods presented:
	Year ended December 31, 2013
(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
				Real Estate		Real Estate		Commercial		Equity		Consumer
Troubled debt restructurings
Number of loans	63			9		21		23		2		8
Pre-modification recorded balance	$	29,046		1,907		20,334		6,087		147		571
Post-modification recorded balance	$	29,359		2,293		20,334		6,087		147		498
Troubled debt restructurings that subsequently defaulted
Number of loans	5			1		1		3		—		—
Recorded balance	$	849		265		79		505		—		—
Note 4. Loans Receivable, Net (continued)
	Year ended December 31, 2012
(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
				Real Estate		Real Estate		Commercial		Equity		Consumer
Troubled debt restructurings
Number of loans	198			11		85		75		10		17
Pre-modification recorded balance	$	90,747		2,280		57,382		28,639		1,358		1,088
Post-modification recorded balance	$	89,558		2,281		56,120		28,711		1,358		1,088
Troubled debt restructurings that subsequently defaulted
Number of loans	14			—		4		6		3		1
Recorded balance	$	8,304		—		6,192		1,753		301		58
	Year ended December 31, 2011
(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
				Real Estate		Real Estate		Commercial		Equity		Consumer
Troubled debt restructurings
Number of loans	338			20		120		149		22		27
Pre-modification recorded balance	$	158,295		13,500		109,593		20,446		9,198		5,558
Post-modification recorded balance	$	155,827		13,452		107,778		20,434		9,200		4,963
Troubled debt restructurings that subsequently defaulted
Number of loans	66			4		29		22		7		4
Recorded balance	$	41,236		2,291		32,615		2,718		3,202		410
For the years ended December 31, 2013, 2012 and 2011 the majority of TDRs occurring in most loan classes was a result of an extension of the maturity date which aggregated 71 percent, 49 percent and 58 percent, respectively, of total TDRs. For commercial real estate, the class with the largest dollar amount of TDRs, approximately 87 percent, 36 percent and 56 percent, respectively, was a result of an extension of the maturity date and 9 percent, 30 percent and 31 percent, respectively, was due to a combination of an interest rate reduction, extension of the maturity date, or reduction in the face amount.
In addition to the TDRs that occurred during the period provided in the preceding table, the Company had TDRs with pre-modification loan balances of $18,345,000, $39,769,000 and $96,528,000 for the years ended December 31, 2013, 2012 and 2011, respectively, for which OREO was received in full or partial satisfaction of the loans. The majority of such TDRs for all years was in commercial real estate.
There were $2,024,000 and $4,534,000 of additional unfunded commitments on TDRs outstanding at December 31, 2013 and 2012, respectively. The amount of charge-offs on TDRs during 2013, 2012 and 2011 was $1,945,000, $6,271,000 and $8,792,000, respectively.

Premises_and_Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment [Abstract]	'
Premises and Equipment	'
	Note 5. Premises and Equipment
	Premises and equipment, net of accumulated depreciation, consist of the following at:
	(Dollars in thousands)	31-Dec-13			31-Dec-12
	Land	$	27,260		25,027
	Office buildings and construction in progress	159,391			153,340
	Furniture, fixtures and equipment	66,375			63,467
	Leasehold improvements	7,589			7,393
	Accumulated depreciation	(92,944		)	(90,238	)
	Net premises and equipment	$	167,671		158,989
	Depreciation expense for the years ended December 31, 2013, 2012, and 2011 was $10,485,000, $10,615,000, and $10,443,000, respectively.
	The Company leases certain land, premises and equipment from third parties under operating and capital leases. Total rent expense for the years ended December 31, 2013, 2012, and 2011 was $2,912,000, $2,868,000, and $3,239,000, respectively. Amortization of building capital lease assets is included in depreciation. The Company has entered into lease transactions with related parties. Rent expense with such related parties for the years ended December 31, 2013, 2012, and 2011 was $142,000, $410,000, and $937,000. The decrease in the related party rent expense from the prior years was due to combining the bank subsidiaries in 2012, which resulted in a decrease in the number of related parties.
	The total future minimum rental commitments required under operating and capital leases that have initial or remaining noncancelable lease terms in excess of one year at December 31, 2013 are as follows:
	(Dollars in thousands)	Capital			Operating		Total
		Leases			Leases
	Years ending December 31,
	2014	$	828		2,297		3,125
	2015	195			2,120		2,315
	2016	197			1,879		2,076
	2017	200			1,577		1,777
	2018	203			1,375		1,578
	Thereafter	546			2,900		3,446
	Total minimum lease payments	2,169			12,148		14,317
	Less: Amount representing interest	479
	Present value of minimum lease payments	1,690
	Less: Current portion of obligations under capital leases	708
	Long-term portion of obligations under capital leases	$	982

Other_Intangible_Assets_and_Go

Other Intangible Assets and Goodwill	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Other Intangible Assets and Goodwill	'
	Note 6. Other Intangible Assets and Goodwill
	The following table sets forth information regarding the Company’s core deposit intangibles:
		At or for the Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Gross carrying value	$	27,857		22,404		28,248
	Accumulated amortization	(18,345		)	(16,230	)	(19,964	)
	Net carrying value	$	9,512		6,174		8,284
	Aggregate amortization expense	$	2,401		2,110		2,473
	Weighted-average amortization period
	(Period in years)	9.5
	Estimated amortization expense for the years ending December 31,
	2014	$	2,650
	2015	2,198
	2016	1,700
	2017	828
	2018	430
	Core deposit intangibles increased $5,739,000 during 2013 due to the acquisitions of Wheatland and NCBI. For additional information relating to acquisitions, see Note 22.
	The following schedule discloses the changes in the carrying value of goodwill:
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Net carrying value at beginning of period	$	106,100		106,100		146,259
	Acquisitions	23,606			—		—
	Impairment charge	—			—		(40,159	)
	Net carrying value at end of period	$	129,706		106,100		106,100
	The gross carrying value of goodwill and the accumulated impairment charge consists of the following:
	(Dollars in thousands)	December 31,			December 31,
		2013			2012
	Gross carrying value	$	169,865		146,259
	Accumulated impairment charge	(40,159		)	(40,159	)
	Net carrying value	$	129,706		106,100
	Note 6. Other Intangible Assets and Goodwill (continued)
	The Company’s first step in evaluating goodwill for possible impairment is a control premium analysis. The analysis first calculates the market capitalization and then adjusts such value for a control premium range which results in an implied fair value. The control premium range is determined based on historical control premiums for acquisitions that are comparable to the Company and is obtained from an independent third party. The calculated implied fair value is then compared to the book value to determine whether the Company needs to proceed to step two of the goodwill impairment assessment. The Company performed its annual goodwill impairment test during the third quarter of 2013 and determined the fair value of the aggregated reporting units exceeded the carrying value, such that the Company’s goodwill was not considered impaired. In recognition there were no events or circumstances that occurred during the fourth quarter of 2013 that would more-likely-than-not reduce the fair value of a reporting unit below its carrying value, the Company did not perform interim testing at December 31, 2013. However, changes in the economic environment, operations of the aggregated reporting units, or other factors could result in the decline in the fair value of the aggregated reporting units which could result in a goodwill impairment in the future. Due to high levels of volatility and dislocation in prices of shares of publicly-held, exchange listed banking companies in 2011, a goodwill impairment charge was recognized by the Company during the third quarter of 2011. The method utilized for the 2011 two-step impairment analysis and the corresponding amount of the impairment charge included quoted stock market prices for other banks, discounted cash flows and inputs from comparable transactions.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2013
Deposits [Abstract]	'
Deposits	'
	Note 7. Deposits
	Deposits consist of the following at:
	(Dollars in thousands)	December 31, 2013				December 31, 2012
	Non-interest bearing deposits	$	1,374,419	24.6	%	1,191,933	22.2	%
	NOW accounts	1,113,878		20	%	988,984	18.4	%
	Savings accounts	600,998		10.8	%	478,809	8.9	%
	Money market deposit accounts	1,168,918		20.9	%	931,370	17.4	%
	Certificate accounts	1,116,622		20	%	1,015,491	19	%
	Wholesale deposits 1	205,132		3.7	%	757,874	14.1	%
	Total interest bearing deposits	4,205,548		75.4	%	4,172,528	77.8	%
	Total deposits	$	5,579,967	100	%	5,364,461	100	%
	Deposits with a balance of $100,000 and greater
	Demand deposits	$	2,685,577			2,361,528
	Certificate accounts	661,924				1,044,488
	Total balances of $100,000 and greater	$	3,347,501			3,406,016
	__________
	1 Wholesale deposits include brokered deposits classified as NOW, money market deposit and certificate accounts.
	The scheduled maturities of time deposits are as follows and include $51,979,000 of wholesale deposits as of December 31, 2013:
	(Dollars in thousands)	Amount
	Years ending December 31,
	2014	$	864,633
	2015	164,104
	2016	79,425
	2017	33,975
	2018	19,244
	Thereafter	7,220
		$	1,168,601
	Note 7. Deposits (continued)
	The Company reclassified $3,422,000 and $3,482,000 of overdraft demand deposits to loans as of December 31, 2013 and 2012, respectively. The Company has entered into deposit transactions with its executive officers and directors and their affiliates. The aggregate amount of deposits with such related parties at December 31, 2013, and 2012 was $12,770,000 and $20,404,000, respectively.
	Debit card expense for the years ended December 31, 2013, 2012, and 2011 was $6,131,000, $4,497,000, and $4,400,000, respectively, and was included in other expense in the Company’s statements of operations.

Securities_Sold_Under_Agreemen

Securities Sold Under Agreements to Repurchase	12 Months Ended
	Dec. 31, 2013
Securities Financing Transactions Disclosures [Abstract]	'
Securities Sold Under Agreements to Repurchase	'
	Note 8. Securities Sold Under Agreements to Repurchase
	Repurchase agreements consist of the following:
		December 31, 2013
	(Dollars in thousands)	Repurchase		Weighted-		Amortized		Fair
		Amount		Average		Cost of		Value of
				Fixed Rate		Underlying		Underlying
						Assets		Assets
	Overnight	$	303,709	0.28	%	$	304,263	312,856
	Maturing within 30 days	9,685		0.32	%	11,095		11,301
		$	313,394	0.28	%	$	315,358	324,157
		December 31, 2012
	(Dollars in thousands)	Repurchase		Weighted-		Amortized		Fair
		Amount		Average		Cost of		Value of
				Fixed Rate		Underlying		Underlying
						Assets		Assets
	Overnight	$	285,349	0.32	%	$	287,597	293,958
	Maturing within 30 days	4,159		0.5	%	4,228		4,306
		$	289,508	0.32	%	$	291,825	298,264
	The securities, consisting of U.S. government sponsored enterprises issued or guaranteed residential mortgage-backed securities, subject to agreements to repurchase, were for the same securities originally sold, and were held in custody accounts by third parties. The fair value of collateral utilized for repurchase agreements is continually monitored and additional collateral is provided as deemed appropriate.

Borrowings

Borrowings	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Borrowings	'
	Note 9. Borrowings
	Each FHLB advance bears a fixed rate of interest and consists of the following:
		December 31, 2013				December 31, 2012
	(Dollars in thousands)	Amount		Weighted		Amount		Weighted
				Rate				Rate
	Maturing within one year	$	559,084	0.24	%	$	720,000	0.28	%
	Maturing one year through two years	77,979		3.36	%	—		—	%
	Maturing two years through three years	45,042		2.99	%	75,000		3.48	%
	Maturing three years through four years	—		—	%	45,000		2.99	%
	Maturing four years through five years	20,250		2.83	%	—		—	%
	Thereafter	137,827		3.12	%	157,013		3.07	%
	Total	$	840,182	1.21	%	$	997,013	1.09	%
	Note 9. Borrowings (continued)
	In addition to specifically pledged loans and investment securities, FHLB advances are collateralized by FHLB stock owned by the Company and a blanket assignment of the unpledged qualifying loans and investments.
	With respect to $275,000,000 of FHLB advances at December 31, 2013, FHLB holds put options that will be exercised on the quarterly measurement date when 3-month LIBOR is 8 percent or greater. The FHLB put options as of December 31, 2013 are summarized as follows:
	(Dollars in thousands)	Amount		Interest
				Rate
	Maturing during years ending December 31,
	2015	$	75,000	3.16% - 3.64%
	2016	45,000		2.93% - 3.05%
	2018	20,000		2.73% - 2.85%
	2021	135,000		2.88% - 3.43%
		$	275,000
	The Company’s remaining borrowings consisted of capital lease obligations, liens on OREO and other debt obligations through consolidation of certain VIEs. At December 31, 2013, the Company had $255,000,000 in unsecured lines of credit which are typically renewed on an annual basis with various correspondent entities.

Subordinated_Debentures

Subordinated Debentures	12 Months Ended
	Dec. 31, 2013
Subordinate Debenture [Abstract]	'
Subordinated Debentures	'
	Note 10. Subordinated Debentures
	Trust preferred securities were issued by the Company’s trust subsidiaries, the common stock of which is wholly-owned by the Company, in conjunction with the Company issuing subordinated debentures to the trust subsidiaries. The terms of the subordinated debentures are the same as the terms of the trust preferred securities. The Company guaranteed the payment of distributions and payments for redemption or liquidation of the trust preferred securities to the extent of funds held by the trust subsidiaries. The obligations of the Company under the subordinated debentures together with the guarantee and other back-up obligations, in the aggregate, constitute a full and unconditional guarantee by the Company of the obligations of all trusts under the trust preferred securities.
	The trust preferred securities are subject to mandatory redemption upon repayment of the subordinated debentures at their stated maturity date or the earlier redemption in an amount equal to their liquidation amount plus accumulated and unpaid distributions to the date of redemption. Interest distributions are payable quarterly. The Company may defer the payment of interest at any time from time to time for a period not exceeding 20 consecutive quarters provided that the deferral period does not extend past the stated maturity. During any such deferral period, distributions on the trust preferred securities will also be deferred and the Company’s ability to pay dividends on its common shares will be restricted.
	Subject to prior approval by the FRB, the trust preferred securities may be redeemed at par prior to maturity at the Company’s option on or after the redemption date. All of the Company’s trust preferred securities have reached the redemption date and could be redeemed at the Company’s option. The trust preferred securities may also be redeemed at any time in whole (but not in part) for the Trusts in the event of unfavorable changes in laws or regulations that result in 1) subsidiary trusts becoming subject to federal income tax on income received on the subordinated debentures, 2) interest payable by the Company on the subordinated debentures becoming non-deductible for federal tax purposes, 3) the requirement for the trusts to register under the Investment Company Act of 1940, as amended, or 4) loss of the ability to treat the trust preferred securities as Tier 1 capital under the FRB capital adequacy guidelines.
	For regulatory purposes, the FRB has allowed bank holding companies to include trust preferred securities in Tier 1 capital up to a certain limit. Provisions of the Dodd-Frank Act require the FRB to exclude trust preferred securities from Tier 1 capital, but a grandfather provision permits bank holding companies with consolidated assets of less than $15 billion to continue counting existing trust preferred securities as Tier 1 capital until they mature. All of the Company’s trust preferred securities qualified as Tier 1 instruments at December 31, 2013.
	Note 10. Subordinated Debentures (continued)
	The terms of the subordinated debentures, arranged by maturity date, are reflected in the table below. The amounts include fair value adjustments from acquisitions.
		31-Dec-13				Variable Rate Structure	Maturity Date
	(Dollars in thousands)	Balance		Rate
	First Company Statutory Trust 2001	$	3,018	3.537	%	3 mo LIBOR plus 3.30	7/31/31
	First Company Statutory Trust 2003	2,227		3.496	%	3 mo LIBOR plus 3.25	3/26/33
	Glacier Capital Trust II	46,393		2.994	%	3 mo LIBOR plus 2.75	4/7/34
	Citizens (ID) Statutory Trust I	5,155		2.894	%	3 mo LIBOR plus 2.65	6/17/34
	Glacier Capital Trust III	36,083		1.533	%	3 mo LIBOR plus 1.29	4/7/36
	Glacier Capital Trust IV	30,928		1.813	%	3 mo LIBOR plus 1.57	9/15/36
	Bank of the San Juans Bancorporation Trust I	1,758		2.058	%	3 mo LIBOR plus 1.82	3/1/37
		$	125,562

Derivatives_and_Hedging_Activi

Derivatives and Hedging Activities	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivatives and Hedging Activities	'
	Note 11. Derivatives and Hedging Activities
	The Company is exposed to certain risk relating to its ongoing business operations. The primary risk managed by using derivative instruments is interest rate risk. Interest rate swaps are entered into to manage interest rate risk associated with the Company’s forecasted variable rate borrowings. The Company recognizes interest rate swaps as either assets or liabilities at fair value in the statements of financial condition, after taking into account the effects of bilateral collateral and master netting agreements. These agreements allow the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset net interest rate swap derivative positions with related collateral, where applicable. As a result, the Company could have interest rate swaps with negative fair values included in other assets on the statements of financial condition and interest rate swaps with positive fair values included in other liabilities.
	The interest rate swaps on variable rate borrowings were designated as cash flow hedges and were over-the-counter contracts. The contracts were entered into by the Company with a single counterparty and the specific agreement of terms were negotiated, including forecasted notional amounts, interest rates and maturity dates.
	The Company is exposed to credit-related losses in the event of nonperformance by the counterparty to the agreements. The Company controls the credit risk through monitoring procedures and does not expect the counterparty to fail on its obligations. The Company only conducts business with primary dealers as and believes that the credit risk inherent in these contracts was not significant.
	The Company’s interest rate swap derivative financial instruments as of December 31, 2013 are as follows:
	(Dollars in thousands)	Forecasted		Variable		Fixed		Term 2
		Notional  Amount		Interest Rate 1		Interest Rate 1
	Interest rate swap	$	160,000	3 month LIBOR		3.378	%	Oct. 21, 2014 - Oct. 21, 2021
	Interest rate swap	100,000		3 month LIBOR		2.498	%	Nov 30, 2015 - Nov. 30, 2022
	__________
	1 The Company pays the fixed interest rate and the counterparty pays the Company the variable interest rate.
	2 No cash will be exchanged prior to the term.
	The hedging strategy converts the LIBOR based variable interest rate on forecasted borrowings to a fixed interest rate, thereby protecting the Company from floating interest rate variability.
	Note 11. Derivatives and Hedging Activities (continued)
	The following table discloses the offsetting of financial assets and interest rate swap derivative assets:
		December 31, 2013							December 31, 2012
	(Dollars in thousands)	Gross Amounts of Recognized Assets		Gross Amounts Offset in the Statements of Financial Position			Net Amounts of Assets Presented in the Statements of Financial Position		Gross Amounts of Recognized Assets	Gross Amounts Offset in the Statements of Financial Position	Net Amounts of Assets Presented in the Statements of Financial Position
	Interest rate swaps	$	6,844	(4,948	)		1,896		—	—	—
	The following table discloses the offsetting of financial liabilities and interest rate swap derivative liabilities:
		December 31, 2013							December 31, 2012
	(Dollars in thousands)	Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Statements of Financial Position			Net Amounts of Liabilities Presented in the Statements of Financial Position		Gross Amounts of Recognized Liabilities	Gross Amounts Offset in the Statements of Financial Position	Net Amounts of Liabilities Presented in the Statements of Financial Position
	Interest rate swaps	$	4,948	(4,948	)		—		16,832	—	16,832
	Pursuant to the interest rate swap agreements, the Company pledged collateral to the counterparty in the form of investment securities totaling $6,918,000 at December 31, 2013. There was $0 collateral pledged from the counterparty to the Company as of December 31, 2013. There is the possibility that the Company may need to pledge additional collateral in the future if there were declines in the fair value of the interest rate swap derivative financial instruments versus the collateral pledged.

Regulatory_Capital

Regulatory Capital	12 Months Ended
	Dec. 31, 2013
Banking and Thrift [Abstract]	'
Regulatory Capital	'
	Note 12. Regulatory Capital
	The FRB has adopted capital adequacy guidelines pursuant to which it assesses the adequacy of capital in supervising a bank holding company. The following tables illustrate the FRB’s adequacy guidelines and the Company’s and the Bank’s compliance with those guidelines:
		31-Dec-13
		Actual				Minimum Capital				Well Capitalized
						Requirement				Requirement
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	Total capital (to risk-weighted assets)
	Consolidated	$	1,005,980	18.97	%	$	424,322	8	%	$	530,402	10	%
	Glacier Bank	948,618		17.93	%	423,235		8	%	529,044		10	%
	Tier 1 capital (to risk-weighted assets)
	Consolidated	$	938,887	17.7	%	$	212,161	4	%	$	318,241	6	%
	Glacier Bank	881,692		16.67	%	211,618		4	%	317,426		6	%
	Tier 1 capital (to average assets)
	Consolidated	$	938,887	12.11	%	$	310,082	4	%	N/A		N/A
	Glacier Bank	881,692		11.44	%	308,281		4	%	$	385,351	5	%
	Note 12. Regulatory Capital (continued)
		31-Dec-12
		Actual				Minimum Capital				Well Capitalized
						Requirement				Requirement
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	Total capital (to risk-weighted assets)
	Consolidated	$	923,574	20.09	%	$	367,701	8	%	$	459,627	10	%
	Glacier Bank	851,819		18.79	%	362,711		8	%	453,388		10	%
	Tier 1 capital (to risk-weighted assets)
	Consolidated	$	865,213	18.82	%	$	183,851	4	%	$	275,776	6	%
	Glacier Bank	794,228		17.52	%	181,355		4	%	272,033		6	%
	Tier 1 capital (to average assets)
	Consolidated	$	865,213	11.31	%	$	306,005	4	%	N/A		N/A
	Glacier Bank	794,228		10.55	%	301,013		4	%	$	376,267	5	%
	The Federal Deposit Insurance Corporation Improvement Act generally restricts a depository institution from making any capital distribution (including payment of a dividend) or paying any management fee to its bank holding company if the institution would thereafter be capitalized at less than 8 percent Total capital (to risk-weighted assets), 4 percent Tier 1 capital (to risk-weighted assets), or 4 percent Tier 1 capital (to average assets).
	At December 31, 2013 and 2012, the Bank’s capital measures exceeded the well capitalized threshold, which requires Total capital (to risk-weighted assets) of at least 10 percent, Tier 1 capital (to risk-weighted assets) of at least 6 percent, and Tier 1 capital (to average assets) of at least 5 percent. Failure to meet minimum capital requirements can initiate certain mandatory and possible additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s and Bank’s financial condition. There are no conditions or events since year end that management believes have changed the Company’s or Bank’s risk-based capital category.
	Current guidance from the Federal Reserve provides, among other things, that dividends per share on the Company’s common stock generally should not exceed earnings per share, measured over the previous four fiscal quarters. The Bank is also subject to Montana state law and cannot declare a dividend greater than the previous two years’ net earnings without providing notice to the state.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Accumulated Other Comprehensive Income	'
	Note 13. Accumulated Other Comprehensive Income
	The components of accumulated other comprehensive income, included in stockholders’ equity, are as follows:
	(Dollars in thousands)	31-Dec-13			31-Dec-12
	Unrealized gains on available-for-sale securities	$	13,888		95,328
	Tax effect	(5,403		)	(37,083	)
	Net of tax amount	8,485			58,245
	Unrealized gains (losses) on derivatives used for cash flow hedges	1,896			(16,832	)
	Tax effect	(736		)	6,549
	Net of tax amount	1,160			(10,283	)
	Total accumulated other comprehensive income	$	9,645		47,962

Federal_and_State_Income_Taxes

Federal and State Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Federal and State Income Taxes	'
	Note 14. Federal and State Income Taxes
	The following is a summary of consolidated income tax expense (benefit):
		Years ended
	(Dollars in thousands)	December 31,				December 31,			December 31,
		2013				2012			2011
	Current
	Federal	$	18,377			12,718			8,836
	State	7,007				5,522			4,191
	Total current income tax expense	25,384				18,240			13,027
	Deferred
	Federal	3,918				708			(11,256	)
	State	715				129			(2,052	)
	Total deferred income tax expense (benefit)	4,633				837			(13,308	)
	Total income tax expense (benefit)	$	30,017			19,077			(281	)
	Combined federal and state income tax expense differs from that computed at the federal statutory corporate tax rate as follows:
		Years ended
		December 31,			December 31,			December 31,
		2013			2012			2011
	Federal statutory rate	35	%		35	%		35	%
	State taxes, net of federal income tax benefit	4	%		3.9	%		8.1	%
	Tax-exempt interest income	(12.2	)%		(14.0	)%		(65.5	)%
	Tax credits	(3.2	)%		(4.2	)%		(22.1	)%
	Goodwill impairment charge	—	%		—	%		42.3	%
	Other, net	0.3	%		(0.5	)%		0.6	%
	Effective tax rate	23.9	%		20.2	%		(1.6	)%
	Note 14. Federal and State Income Taxes (continued)
	The tax effect of temporary differences which give rise to a significant portion of deferred tax assets and deferred tax liabilities are as follows:
	(Dollars in thousands)	December 31,				December 31,
		2013				2012
	Deferred tax assets
	Allowance for loan and lease losses	$	50,652			50,963
	Other real estate owned	8,041				7,685
	Deferred compensation	4,837				3,129
	Employee benefits	3,132				2,715
	Federal income tax credits	2,778				3,543
	Interest rate swap agreements	—				6,549
	Other	7,813				7,835
	Total gross deferred tax assets	77,253				82,419
	Deferred tax liabilities
	FHLB stock dividends	(10,359		)		(10,143	)
	Deferred loan costs	(6,058		)		(5,316	)
	Available-for-sale securities	(5,402		)		(37,083	)
	Depreciation of premises and equipment	(3,939		)		(5,437	)
	Intangibles	(3,099		)		(1,117	)
	Interest rate swap agreements	(736		)		—
	Other	(4,111		)		(2,929	)
	Total gross deferred tax liabilities	(33,704		)		(62,025	)
	Net deferred tax asset	$	43,549			20,394
	The Company’s federal income tax credit carryforwards will expire in 2033.
	The Company and the Bank join together in the filing of consolidated income tax returns in the following jurisdictions: federal, Montana, Idaho, Colorado and Utah. Although the Bank has operations in Wyoming and Washington, neither Wyoming nor Washington imposes a corporate-level income tax. All required income tax returns have been timely filed. The following schedule summarizes the years that remain subject to examination as of December 31, 2013:
		Years ended December 31,
	Federal	2009, 2010, 2011 and 2012
	Montana	2010, 2011 and 2012
	Idaho	2009, 2010, 2011 and 2012
	Colorado	2009, 2010, 2011 and 2012
	Utah	2010, 2011 and 2012
	The Company had no unrecognized income tax benefits as of December 31, 2013, and 2012. The Company recognizes interest related to unrecognized income tax benefits in interest expense and penalties are recognized in other expense. Interest expense and penalties recognized with respect to income tax liabilities for the years ended December 31, 2013, 2012, and 2011 was not significant. The Company had no accrued liabilities for the payment of interest or penalties at December 31, 2013, and 2012.
	Note 14. Federal and State Income Taxes (continued)
	The Company has assessed the need for a valuation allowance and determined that a valuation allowance was not necessary at December 31, 2013, and 2012. The Company believes that it is more-likely-than-not that the Company’s deferred tax assets will be realizable by offsetting future taxable income from reversing taxable temporary differences and anticipated future taxable income (exclusive of reversing temporary differences). In its assessment, the Company considered its strong earnings history, no history of income tax credit carryforwards expiring unused, and no future net operating losses (for tax purposes) are expected.
	Retained earnings at December 31, 2013 includes $3,600,000 for which no provision for federal income tax has been made. This amount represents the base year reserve for bad debts, which is essentially an allocation of earnings to pre-1988 bad debt deductions for federal income tax purposes only. This amount is treated as a permanent difference and deferred taxes are not recognized unless it appears that this bad debt reserve will be reduced and thereby result in taxable income in the foreseeable future. The Company is not currently contemplating any changes in its business or operations which would result in a recapture of this reserve for bad debts for federal income tax purposes.

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Note 15. Earnings Per Share
	Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding stock options were exercised and restricted stock awards were vested, using the treasury stock method.
	Basic and diluted earnings per share has been computed based on the following:
		Years ended
	(Dollars in thousands, except per share data)	December 31,		December 31,	December 31,
		2013		2012	2011
	Net income available to common stockholders, basic and diluted	$	95,644	75,516	17,471
	Average outstanding shares - basic	73,191,713		71,928,570	71,915,073
	Add: dilutive stock options and awards	68,565		86	—
	Average outstanding shares - diluted	73,260,278		71,928,656	71,915,073
	Basic earnings per share	$	1.31	1.05	0.24
	Diluted earnings per share	$	1.31	1.05	0.24
	There were 38,915, 879,525 and 1,567,561 options excluded from the diluted average outstanding share calculation for December 31, 2013, 2012, and 2011, respectively, due to the option exercise price exceeding the market price of the Company’s common stock.

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]	'
Employee Benefit Plans	'
	Note 16. Employee Benefit Plans
	The Company has a 401(k) plan and a profit sharing plan which has safe harbor and employer discretionary components. To be considered eligible for the 401(k) and safe harbor components of the profit sharing plan, an employee must be 21 years of age and employed for three full months. Employees are eligible to participate in the 401(k) plan the first day of the month once they have met the eligibility requirements. To be considered eligible for the employer discretionary contribution of the profit sharing plan, an employee must be 21 years of age, worked one full calendar quarter, worked 501 hours in the plan year and be employed as of the last day of the plan year. Participants are at all times fully vested in all contributions.
	The profit sharing plan contributions consists of a 3 percent non-elective safe harbor contribution fully funded by the Company and an employer discretionary contribution. The employer discretionary contribution depends on the Company’s profitability. The total profit sharing plan expense for the years ended December 31, 2013, 2012, and 2011 was $5,862,000, $3,974,000 and $2,043,000 respectively.
	The 401(k) plan allows eligible employees to contribute up to 60 percent of their eligible annual compensation up to the limit set annually by the Internal Revenue Service (“IRS). The Company matches an amount equal to 50 percent of the first 6 percent of an employee’s contribution. The Company’s contribution to the 401(k) for the years ended December 31, 2013, 2012 and 2011 was $1,935,000, $1,751,000, and $1,644,000, respectively.
	The Company has non-funded deferred compensation plans for directors, senior officers and certain nonemployee service providers. The plans provide for participants’ elective deferral of cash payments of up to 50 percent of a participants’ salary and 100 percent of bonuses and directors fees. The total amount deferred for the plans was $376,000, $278,000, and $362,000, for the years ending December 31, 2013, 2012, and 2011, respectively. The participant receives an earnings credit at a rate equal to 50 percent of the Company’s return on average equity. The total earnings for the years ended December 31, 2013, 2012, and 2011 for the plans was $515,000, $231,000 and $54,000, respectively. In connection with several acquisitions, the Company assumed the obligations of deferred compensation plans for certain key employees. As of December 31, 2013 and 2012, the liability related to the obligations was $5,042,000 and $1,255,000 and was included in other liabilities. The total earnings for the years ended December 31, 2013, 2012, and 2011 for the acquired plans was insignificant.
	The Company has a Supplemental Executive Retirement Plan (“SERP”) which is intended to supplement payments due to participants upon retirement under the Company’s other qualified plans. The Company credits the participant’s account on annual basis for an amount equal to employer contributions that would have otherwise been allocated to the participant’s account under the tax-qualified plans were it not for limitations imposed by the IRS or the participation in the non-funded deferred compensation plan. Eligible employees include participants of the non-funded deferred compensation plan and employees whose benefits were limited as a result of IRS regulations. The Company’s required contribution to the SERP for the years ended December 31, 2013, 2012 and 2011 was $76,000, $47,000, and $21,000, respectively. The participant receives an earnings credit at a rate equal to 50 percent of the Company’s return on average equity. The total earnings for the years ended December 31, 2013, 2012, and 2011 for this plan was $48,000, $37,000, and $9,000, respectively.
	The Company has elected to self-insure certain costs related to employee health and dental benefit programs. Costs resulting from noninsured losses are expensed as incurred. The Company has purchased insurance that limits its exposure on an aggregate and individual claims basis for the employee health benefit programs.
	The Company has entered into employment contracts with 26 senior officers that provide benefits under certain conditions following a change in control of the Company.

Stockbased_Compensation_Plans

Stock-based Compensation Plans	12 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Stock-based Compensation Plans	'
	Note 17. Stock-based Compensation Plans
	The Company has the following stock-based compensation plans outstanding: 1) the Directors 1994 Stock Option Plan and 2) the 2005 Stock Incentive Plan. The Directors 1994 Stock Option Plan was approved to provide for the grant of stock options to outside Directors of the Company. The Directors 1994 Stock Option Plan expired in March of 2009 and has granted but unexpired stock options outstanding at December 31, 2013. The 2005 Stock Incentive Plan provides awards to certain full-time employees and directors of the Company. The 2005 Stock Incentive Plan permits the granting of stock options, share appreciation rights, restricted shares, restricted share units, and unrestricted shares, deferred share units, and performance awards. At December 31, 2013, the number of shares available to grant to employees and directors was 4,116,931.
	Stock Options
	The Company has granted stock options to certain full-time employees and directors of the Company under the Directors 1994 Stock Option Plan and the 2005 Stock Incentive Plan. Both plans contain provisions authorizing the grant of limited stock rights, which permit the optionee, upon a change in control of the Company, to surrender his or her stock options for cancellation and receive cash or common stock equal to the difference between the exercise price and the fair market value of the shares on the date of the grant. The option price at which the Company’s common stock may be purchased upon exercise of stock options granted under the plans must be at least equal to the per share market value of such stock at the date the option is granted. All stock option shares are adjusted for stock splits and stock dividends. The term of the stock options may not exceed five years from the date the options are granted.
	The fair value of stock options granted is estimated at the date of grant using the Black Scholes option-pricing model. The Company uses historical data to estimate option exercise and termination within the valuation model. Employee and director awards, which have dissimilar historical exercise behavior, are considered separately for valuation purposes. The risk-free interest rate for periods within the contractual life of the stock option is based on the U.S. Treasury yield in effect at the time of the grant. The stock option grants generally vest upon six months or two years of service for directors and employees, respectively, and generally expire in five years. Expected volatilities are based on historical volatility and other factors. There were no stock options granted during 2013, 2012 or 2011.
	Compensation expense related to stock options for the years ended December 31, 2013, 2012 and 2011 was $0, $4,000 and $74,000, respectively, and the recognized income tax benefit related to this expense was $0, $2,000 and $29,000. There was no unrecognized compensation cost related to stock options as of December 31, 2013.
	The total intrinsic value of options exercised during the years ended December 31, 2013, 2012 and 2011 was $1,907,000, $3,000 and $0, respectively, and the income tax benefit received related to these exercises was $742,000, $1,000 and $0. Total cash received from options exercised during the years ended December 31, 2013, 2012 and 2011 was $4,327,000, $81,000 and $0. Upon exercise of stock options, the shares are issued from the Company’s authorized stock balance.
	Changes in shares granted for stock options for the year ended December 31, 2013 are summarized as follows:
		Options		Weighted-
				Average
				Exercise Price
	Outstanding at December 31, 2012	791,440		$	16.95
	Exercised	(281,560	)	15.37
	Forfeited or expired	(451,070	)	18.14
	Outstanding at December 31, 2013	58,810		15.47
	Exercisable at December 31, 2013	58,810		15.47
	The average remaining life on stock options outstanding and exercisable at December 31, 2013 is one month. The aggregate intrinsic value of the outstanding and exercisable shares at December 31, 2013 was $842,000.
	Note 17. Stock-based Compensation Plans (continued)
	Restricted Stock Awards
	The Company has awarded restricted stock to certain executive officers and directors under the 2005 Stock Incentive Plan. Common stock issued under restricted stock awards may be issued under the terms of a vesting schedule or with an immediate vest and may not be sold or otherwise transferred until restrictions have lapsed. The recipient does not have voting rights until the restricted stock award has vested. Dividends paid on the restricted shares during the restriction period are paid immediately in cash. The fair value of the restricted stock awarded is the closing price of the Company’s common stock on the award date.
	Compensation expense related to restricted stock awards for the years ended December 31, 2013 and 2012 was $768,000 and $243,000, respectively, and the recognized income tax benefit related to this expense was $299,000 and $96,000. As of December 31, 2013, $1,348,000 of total unrecognized compensation costs related to restricted stock awards is expected to be recognized over a weighted-average period of 2.2 years.
	The fair value of restricted stock awards that vested during the years ended December 31, 2013 and 2012 was $197,000 and $243,000, respectively, and the income tax benefit recognized related to these awards was $77,000 and $96,000. Upon vesting of restricted stock awards, the shares are issued from the Company’s authorized stock balance.
	The following table summarizes the restricted stock award activity for the year ended December 31, 2013:
		Restricted Stock		Weighted-
				Average
				Grant Date Fair Value
	Non-vested at December 31, 2012	—		$	—
	Granted	131,262		16.76
	Vested	(11,753	)	16.76
	Forfeited	(2,067	)	16.76
	Non-vested at December 31, 2013	117,442		16.76

Parent_Holding_Company_Informa

Parent Holding Company Information (Condensed)	12 Months Ended
	Dec. 31, 2013
Condensed Financial Information of Parent Company Only Disclosure [Abstract]	'
Parent Holding Company Information (Condensed)	'
	Note 18. Parent Holding Company Information (Condensed)
	The following condensed financial information was the unconsolidated information for the parent holding company:
	Statements of Financial Condition
	(Dollars in thousands)	December 31,			December 31,
		2013			2012
	Assets
	Cash on hand and in banks	$	1,582		2,540
	Interest bearing cash deposits	49,097			9,887
	Cash and cash equivalents	50,679			12,427
	Investment securities, available-for-sale	87			29,457
	Other assets	9,050			23,221
	Investment in subsidiaries	1,040,104			972,218
	Total assets	$	1,099,920		1,037,323
	Liabilities and Stockholders’ Equity
	Subordinated debentures	$	125,562		125,418
	Other liabilities	11,108			10,956
	Total liabilities	136,670			136,374
	Common stock	744			719
	Paid-in capital	690,918			641,737
	Retained earnings	261,943			210,531
	Accumulated other comprehensive income	9,645			47,962
	Total stockholders’ equity	963,250			900,949
	Total liabilities and stockholders’ equity	$	1,099,920		1,037,323
	Statements of Operations
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Income
	Dividends from subsidiaries	$	65,445		78,209		43,450
	Loss on sale of investments	(3,248		)	—		—
	Other income	966			566		864
	Intercompany charges for services	7,387			16,041		14,438
	Total income	70,550			94,816		58,752
	Expenses
	Compensation and employee benefits	9,175			12,392		9,185
	Other operating expenses	6,536			10,267		11,827
	Total expenses	15,711			22,659		21,012
	Income before income tax benefit and equity in undistributed net income (loss) of subsidiaries	54,839			72,157		37,740
	Income tax benefit	3,676			2,319		2,176
	Income before equity in undistributed net income (loss) of subsidiaries	58,515			74,476		39,916
	Equity in undistributed net income (loss) of subsidiaries	37,129			1,040		(22,825	)
	Net Income	$	95,644		75,516		17,091
	Note 18. Parent Holding Company Information (Condensed) (continued)
	Statements of Comprehensive Income
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Net Income	$	95,644		75,516		17,091
	Other Comprehensive (Loss) Income, Net of Tax
	Unrealized (losses) gains on available-for-sale securities	(81,739		)	31,617		63,190
	Reclassification adjustment for losses (gains) included in net income	299			—		(346	)
	Net unrealized (losses) gains on securities	(81,440		)	31,617		62,844
	Tax effect	31,680			(12,300	)	(24,444	)
	Net of tax amount	(49,760		)	19,317		38,400
	Unrealized gains (losses) on derivatives used for cash flow hedges	18,728			(7,926	)	(8,906	)
	Tax effect	(7,285		)	3,084		3,465
	Net of tax amount	11,443			(4,842	)	(5,441	)
	Total other comprehensive (loss) income, net of tax	(38,317		)	14,475		32,959
	Total Comprehensive Income	$	57,327		89,991		50,050
	Statements of Cash Flows
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
Operating Activities
Net income	$	95,644		75,516		17,091
Adjustments to reconcile net income to net cash provided by operating activities:
Subsidiary income (in excess of) less than dividends distributed	(37,129		)	(1,040	)	22,825
Loss on sale of investments	3,248			—		—
Excess tax deficiencies from stock-based compensation	223			8		—
Net change in other assets and other liabilities	2,575			3,684		1,215
Net cash provided by operating activities	64,561			78,168		41,131
Investing Activities
Proceeds from sales, maturities and prepayments of securities available-for-sale	26,561			787		1,376
Changes in investment securities and other stock - intercompany	(946		)	(19,183	)	—
Equity contribution to subsidiaries	(11,336		)	(28,500	)	(1,110	)
Net addition of premises and equipment	(603		)	(2,927	)	(1,920	)
Net cash provided by (used in) investing activities	13,676			(49,823	)	(1,654	)
Financing Activities
Net increase in other borrowed funds	144			143		143
Cash dividends paid	(44,232		)	(47,472	)	(37,395	)
Excess tax deficiencies from stock-based compensation	(223		)	(8	)	—
Proceeds from stock options exercised	4,326			81		—
Net cash used in financing activities	(39,985		)	(47,256	)	(37,252	)
Net increase (decrease) in cash and cash equivalents	38,252			(18,911	)	2,225
Cash and cash equivalents at beginning of year	12,427			31,338		29,113
Cash and cash equivalents at end of year	$	50,679		12,427		31,338

Unaudited_Quarterly_Financial_

Unaudited Quarterly Financial Data	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Unaudited Quarterly Financial Data	'
	Note 19. Unaudited Quarterly Financial Data
	Summarized unaudited quarterly financial data is as follows:
		Quarters ended 2013
	(Dollars in thousands, except per share data)	March 31		June 30	September 30	December 31
	Interest income	$	57,955	62,151	69,531	73,939
	Interest expense	7,458		7,185	7,186	6,929
	Net interest income	50,497		54,966	62,345	67,010
	Provision for loan losses	2,100		1,078	1,907	1,802
	Net interest income after provision for loan losses	48,397		53,888	60,438	65,208
	Non-interest income	22,950		23,222	23,873	23,002
	Non-interest expense	43,434		48,481	50,368	53,034
	Income before income taxes	27,913		28,629	33,943	35,176
	Federal and state income tax expense	7,145		5,927	8,315	8,630
	Net income	20,768		22,702	25,628	26,546
	Basic earnings per share	0.29		0.31	0.35	0.36
	Diluted earnings per share	0.29		0.31	0.35	0.36
		Quarters ended 2012
	(Dollars in thousands, except per share data)	March 31		June 30	September 30	December 31
	Interest income	$	67,884	64,192	62,015	59,666
	Interest expense	9,598		9,044	8,907	8,165
	Net interest income	58,286		55,148	53,108	51,501
	Provision for loan losses	8,625		7,925	2,700	2,275
	Net interest income after provision for loan losses	49,661		47,223	50,408	49,226
	Non-interest income	20,338		21,791	23,974	25,393
	Non-interest expense	49,045		46,190	50,178	48,008
	Income before income taxes	20,954		22,824	24,204	26,611
	Federal and state income tax expense	4,621		3,843	4,760	5,853
	Net income	16,333		18,981	19,444	20,758
	Basic earnings per share	0.23		0.26	0.27	0.29
	Diluted earnings per share	0.23		0.26	0.27	0.29

Fair_Value_of_Assets_and_Liabi

Fair Value of Assets and Liabilities	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value of Assets and Liabilities	'
	Note 20. Fair Value of Assets and Liabilities
	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There is a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The three levels of inputs that may be used to measure fair value are as follows:
	Level 1    Quoted prices in active markets for identical assets or liabilities
	Level 2	Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities
	Level 3	Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities
	Transfers in and out of Level 1 (quoted prices in active markets), Level 2 (significant other observable inputs) and Level 3 (significant unobservable inputs) are recognized on the actual transfer date. There were no transfers between fair value hierarchy levels during the years ended December 31, 2013 and 2012.
	Recurring Measurements
	The following is a description of the inputs and valuation methodologies used for assets and liabilities measured at fair value on a recurring basis, as well as the general classification of such assets and liabilities pursuant to the valuation hierarchy. There have been no significant changes in the valuation techniques during the period ended December 31, 2013.
	Investment securities: fair value for available-for-sale securities is estimated by obtaining quoted market prices for identical assets, where available. If such prices are not available, fair value is based on independent asset pricing services and models, the inputs of which are market-based or independently sourced market parameters, including but not limited to, yield curves, interest rates, volatilities, prepayments, defaults, cumulative loss projections, and cash flows. Such securities are classified in Level 2 of the valuation hierarchy. Where Level 1 or Level 2 inputs are not available, such securities are classified as Level 3 within the hierarchy.
	Fair value determinations of investment securities are the responsibility of the Company’s corporate accounting and treasury departments. The Company obtains fair value estimates from independent third party vendors on a monthly basis. The Company reviews the vendors’ inputs for fair value estimates and the recommended assignments of levels within the fair value hierarchy. The review includes the extent to which markets for investment securities are determined to have limited or no activity, or are judged to be active markets. The Company reviews the extent to which observable and unobservable inputs are used as well as the appropriateness of the underlying assumptions about risk that a market participant would use in active markets, with adjustments for limited or inactive markets. In considering the inputs to the fair value estimates, the Company places less reliance on quotes that are judged to not reflect orderly transactions, or are non-binding indications. In assessing credit risk, the Company reviews payment performance, collateral adequacy, third party research and analyses, credit rating histories and issuers’ financial statements. For those markets determined to be inactive or limited, the valuation techniques used are models for which management has verified that discount rates are appropriately adjusted to reflect illiquidity and credit risk. The Company also independently obtains cash flow estimates that are stressed at levels that exceed those used by the independent third party pricing vendors.
	Interest rate swap derivative financial instruments: fair values for interest rate swap derivative financial instruments are based upon the estimated amounts to settle the contracts considering current interest rates and are calculated using discounted cash flows that are observable or that can be corroborated by observable market data and, therefore, are classified within Level 2 of the valuation hierarchy. The inputs used to determine fair value include the 3 month LIBOR forward curve to estimate variable rate cash inflows and the Fed Funds Effective Swap Rate to estimate the discount rate. The estimated variable rate cash inflows are compared to the fixed rate outflows and such difference is discounted to a present value to estimate the fair value of the interest rate swaps. The Company also obtains and compares the reasonableness of the pricing from an independent third party.
	Note 20. Fair Value of Assets and Liabilities (continued)
	The following schedules disclose the fair value measurement of assets and liabilities measured at fair value on a recurring basis:
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Fair Value December 31, 2013		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Investment securities, available-for-sale
	U.S. government sponsored enterprises	$	10,628	—		10,628		—
	State and local governments	1,385,078		—		1,385,078		—
	Corporate bonds	442,501		—		442,501		—
	Residential mortgage-backed securities	1,384,622		—		1,384,622		—
	Interest rate swaps	1,896		—		1,896		—
	Total assets measured at fair value on a recurring basis	$	3,224,725	—		3,224,725		—
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Fair Value December 31, 2012		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Investment securities, available-for-sale
	U.S. government and federal agency	$	202	—		202		—
	U.S. government sponsored enterprises	17,480		—		17,480		—
	State and local governments	1,214,518		—		1,214,518		—
	Corporate bonds	288,795		—		288,795		—
	Collateralized debt obligations	1,708		—		1,708		—
	Residential mortgage-backed securities	2,160,302		—		2,160,302		—
	Total assets measured at fair value on a recurring basis	$	3,683,005	—		3,683,005		—
	Interest rate swaps	$	16,832	—		16,832		—
	Total liabilities measured at fair value on a recurring basis	$	16,832	—		16,832		—
	Non-recurring Measurements
	The following is a description of the inputs and valuation methodologies used for assets recorded at fair value on a non-recurring basis, as well as the general classification of such assets pursuant to the valuation hierarchy. There have been no significant changes in the valuation techniques during the year ended December 31, 2013.
	Other real estate owned: OREO is carried at the lower of fair value at acquisition date or current estimated fair value, less estimated cost to sell. Estimated fair value of OREO is based on appraisals or evaluations (new or updated). OREO is classified within Level 3 of the fair value hierarchy.
	Note 20. Fair Value of Assets and Liabilities (continued)
	Collateral-dependent impaired loans, net of ALLL: loans included in the Company’s loan portfolio for which it is probable that the Company will not collect all principal and interest due according to contractual terms are considered impaired. Estimated fair value of collateral-dependent impaired loans is based on the fair value of the collateral, less estimated cost to sell. Collateral-dependent impaired loans are classified within Level 3 of the fair value hierarchy.
	The Company’s credit departments review appraisals for OREO and collateral-dependent loans, giving consideration to the highest and best use of the collateral. The appraisal or evaluation (new or updated) is considered the starting point for determining fair value. The valuation techniques used in preparing appraisals or evaluations (new or updated) include the cost approach, income approach, sales comparison approach, or a combination of the preceding valuation techniques. The key inputs used to determine the fair value of the collateral-dependent loans and OREO include selling costs, discounted cash flow rate or capitalization rate, and adjustment to comparables. Valuations and significant inputs obtained by independent sources are reviewed by the Company for accuracy and reasonableness. The Company also considers other factors and events in the environment that may affect the fair value. The appraisals or evaluations (new or updated) are reviewed at least quarterly and more frequently based on current market conditions, including deterioration in a borrower’s financial condition and when property values may be subject to significant volatility. After review and acceptance of the collateral appraisal or evaluation (new or updated), adjustments to the impaired loan or OREO may occur. The Company generally obtains appraisals or evaluations (new or updated) annually.
	The following schedules disclose the fair value measurement of assets with a recorded change during the period resulting from re-measuring the assets at fair value on a non-recurring basis:
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Fair Value December 31, 2013		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Other real estate owned	$	10,888	—		—		10,888
	Collateral-dependent impaired loans, net of ALLL	18,670		—		—		18,670
	Total assets measured at fair value on a non-recurring basis	$	29,558	—		—		29,558
				Fair Value Measurements
				At the End of the Reporting Period Using
(Dollars in thousands)	Fair Value December 31, 2012		Quoted Prices		Significant		Significant
			in Active  Markets		Other		Unobservable
			for Identical		Observable		Inputs
			Assets		Inputs		(Level 3)
			(Level 1)		(Level 2)
Other real estate owned	$	13,983	—		—		13,983
Collateral-dependent impaired loans, net of ALLL	22,966		—		—		22,966
Total assets measured at fair value on a non-recurring basis	$	36,949	—		—		36,949
Note 20. Fair Value of Assets and Liabilities (continued)
Non-recurring Measurements Using Significant Unobservable Inputs (Level 3)
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 value:
	Fair Value		Quantitative Information about Level 3 Fair Value Measurements
(Dollars in thousands)	December 31,		Valuation Technique	Unobservable Input		Range (Weighted- Average) 1
	2013
Other real estate owned	$	9,278	Sales comparison approach	Selling costs		7.0% - 10.0% (7.7%)
				Adjustment to comparables		0.0% - 37.5% (1.4%)
	1,610		Combined approach	Selling costs		5.0% - 10.0% (7.5%)
				Discount rate		8.5% - 8.5% (8.5%)
				Adjustment to comparables		25.0% - 25.0% (25.0%)
	$	10,888
Collateral-dependent impaired loans, net of ALLL	$	4,076	Income approach	Selling costs		8.0% - 8.0% (8.0%)
				Discount rate		8.3% - 8.3% (8.3%)
	11,784		Sales comparison approach	Selling costs		0.0% - 10.0% (7.9%)
				Adjustment to comparables		0.0% - 1.0% (0.0%)
	2,810		Combined approach	Selling costs		0.0% - 8.0% (7.8%)
				Discount rate		7.3% - 7.3% (7.3%)
				Adjustment to comparables		10.0% - 50.0% (18.9%)
	$	18,670
	Fair Value		Quantitative Information about Level 3 Fair Value Measurements
(Dollars in thousands)	December 31,		Valuation Technique	Unobservable Input		Range (Weighted- Average) 1
	2012
Other real estate owned	$	93	Cost approach	Selling costs		7.0% - 7.0% (7.0%)
	11,787		Sales comparison approach	Selling costs		7.0% - 14.0% (7.9%)
				Adjustment to comparables		0.0% - 37.0% (11.7%)
	2,103		Combined approach	Selling costs		5.0% - 8.0% (6.6%)
				Discount rate		25.0% - 25.0% (25.0%)
				Adjustment to comparables		0.0% - 30.0% (7.7%)
	$	13,983
Collateral-dependent impaired loans, net of ALLL	$	84	Cost approach	Selling costs		8.0% - 8.0% (8.0%)
	5,509		Income approach	Selling costs		8.0% - 10.0% (8.2%)
				Discount rate		0.0% - 8.3% (6.3%)
	12,878		Sales comparison approach	Selling costs		0.0% - 16.0% (8.6%)
				Adjustment to comparables		0.0% - 12.0% (1.6%)
	4,495		Combined approach	Selling costs		8.0% - 10.0% (8.4%)
				Discount rate		8.0% - 8.0% (8.0%)
				Adjustment to comparables		0.0% - 36.0% (17.6%)
	$	22,966
__________
1 The range for selling costs and adjustments to comparables indicate reductions to the fair value.
Note 20. Fair Value of Assets and Liabilities (continued)
Fair Value of Financial Instruments
The following is a description of the methods used to estimate the fair value of all other assets and liabilities recognized at amounts other than fair value.
Cash and cash equivalents: fair value is estimated at book value.
Loans held for sale: fair value is estimated at book value.
Loans receivable, net of ALLL: fair value is estimated by discounting the future cash flows using the rates at which similar notes would be written for the same remaining maturities. The market rates used are based on current rates the Company would impose for similar loans and reflect a market participant assumption about risks associated with non-performance, illiquidity, and the structure and term of the loans along with local economic and market conditions. Estimated fair value of impaired loans is based on the fair value of the collateral, less estimated cost to sell, or the present value of the loan’s expected future cash flows (discounted at the loan’s effective interest rate). All impaired loans are classified as Level 3 and all other loans are classified as Level 2 within the valuation hierarchy.
Accrued interest receivable: fair value is estimated at book value.
Non-marketable equity securities: fair value is estimated at book value due to restrictions that limit the sale or transfer of such securities.
Deposits: fair value of term deposits is estimated by discounting the future cash flows using rates of similar deposits with similar maturities. The market rates used were obtained from an independent third party and reviewed by the Company. The rates were the average of current rates offered by the Company’s local competitors. The estimated fair value of demand, NOW, savings, and money market deposits is the book value since rates are regularly adjusted to market rates and transactions are executed at book value daily. Therefore, such deposits are classified in Level 1 of the valuation hierarchy. Certificate accounts and wholesale deposits are classified as Level 2 within the hierarchy.
FHLB advances: fair value of non-callable FHLB advances is estimated by discounting the future cash flows using rates of similar advances with similar maturities. Such rates were obtained from current rates offered by FHLB. The estimated fair value of callable FHLB advances was obtained from FHLB and the model was reviewed by the Company, including discussions with FHLB.
Repurchase agreements and other borrowed funds: fair value of term repurchase agreements and other term borrowings is estimated based on current repurchase rates and borrowing rates currently available to the Company for repurchases and borrowings with similar terms and maturities. The estimated fair value for overnight repurchase agreements and other borrowings is book value.
Subordinated debentures: fair value of the subordinated debt is estimated by discounting the estimated future cash flows using current estimated market rates. The market rates used were averages of currently traded trust preferred securities with similar characteristics to the Company’s issuances and obtained from an independent third party.
Accrued interest payable: fair value is estimated at book value.
Off-balance sheet financial instruments: commitments to extend credit and letters of credit represent the principal categories of off-balance sheet financial instruments. Rates for these commitments are set at time of loan closing, such that no adjustment is necessary to reflect these commitments at market value. The Company has an insignificant amount of off-balance sheet financial instruments.
Note 20. Fair Value of Assets and Liabilities (continued)
The following schedules present the carrying amounts, estimated fair values and the level within the fair value hierarchy of the Company’s financial instruments:
			Fair Value Measurements
			At the End of the Reporting Period Using
(Dollars in thousands)	Carrying Amount December 31, 2013		Quoted Prices		Significant		Significant
			in Active  Markets		Other		Unobservable
			for Identical		Observable		Inputs
			Assets		Inputs		(Level 3)
			(Level 1)		(Level 2)
Financial assets
Cash and cash equivalents	$	155,657	155,657		—		—
Investment securities, available-for-sale	3,222,829		—		3,222,829		—
Loans held for sale	46,738		46,738		—		—
Loans receivable, net of ALLL	3,932,487		—		3,807,993		187,731
Accrued interest receivable	41,898		41,898		—		—
Non-marketable equity securities	52,192		—		52,192		—
Interest rate swaps	1,896		—		1,896		—
Total financial assets	$	7,453,697	244,293		7,084,910		187,731
Financial liabilities
Deposits	$	5,579,967	4,258,213		1,341,382		—
FHLB advances	840,182		—		857,551		—
Repurchase agreements and other borrowed funds	321,781		—		321,781		—
Subordinated debentures	125,562		—		71,501		—
Accrued interest payable	3,505		3,505		—		—
Total financial liabilities	$	6,870,997	4,261,718		2,592,215		—
			Fair Value Measurements
			At the End of the Reporting Period Using
(Dollars in thousands)	Carrying Amount December 31, 2012		Quoted Prices		Significant		Significant
			in Active  Markets		Other		Unobservable
			for Identical		Observable		Inputs
			Assets		Inputs		(Level 3)
			(Level 1)		(Level 2)
Financial assets
Cash and cash equivalents	$	187,040	187,040		—		—
Investment securities, available-for-sale	3,683,005		—		3,683,005		—
Loans held for sale	145,501		145,501		—		—
Loans receivable, net of ALLL	3,266,571		—		3,184,987		186,201
Accrued interest receivable	37,770		37,770		—		—
Non-marketable equity securities	48,812		—		48,812		—
Total financial assets	$	7,368,699	370,311		6,916,804		186,201
Financial liabilities
Deposits	$	5,364,461	3,585,126		1,789,134		—
FHLB advances	997,013		—		1,027,101		—
Repurchase agreements and other borrowed funds	299,540		—		299,540		—
Subordinated debentures	125,418		—		70,895		—
Accrued interest payable	4,675		4,675		—		—
Interest rate swaps	16,832		—		16,832		—
Total financial liabilities	$	6,807,939	3,589,801		3,203,502		—

Contingencies_and_Commitments

Contingencies and Commitments	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Contingencies and Commitments	'
	Note 21. Contingencies and Commitments
	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 letters of credit, and involve, to varying degrees, elements of credit risk. The Company’s exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit is represented by the contractual amount of those instruments. The Company uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments.
	The Company had the following outstanding commitments:
	(Dollars in thousands)	December 31,		December 31,
		2013		2012
	Commitments to extend credit	$	866,885	802,595
	Letters of credit	14,665		12,600
	Total outstanding commitments	$	881,550	815,195
	The Company is a defendant in legal proceedings arising in the normal course of business. In the opinion of management, the disposition of pending litigation will not have a material affect on the Company’s consolidated financial position, results of operations or liquidity.

Mergers_and_Acquisitions

Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2013
Business Combinations [Abstract]	'
Mergers and Acquisitions	'
	Note 22. Mergers and Acquisitions
	On May 31, 2013, the Company acquired 100 percent of the outstanding common stock of Wheatland and its wholly-owned subsidiary, First State Bank, a community bank based in Wheatland, Wyoming. First State Bank provides community banking services to individuals and businesses from banking offices in Wheatland, Torrington and Guernsey, Wyoming. As a result of the acquisition, the Company has increased its presence in the State of Wyoming and further diversified its loan, customer and deposit base with First State Bank’s strong commitment to agriculture. First State Bank operates as a division of the Bank under the name “First State Bank, division of Glacier Bank.” The Wheatland acquisition was valued at $39,315,000 and resulted in the Company issuing 1,455,256 shares of its common stock and $11,025,000 in cash in exchange for all of Wheatland’s outstanding common stock shares. The fair value of the Company’s common stock shares issued was determined on the basis of the closing market price of the Company’s common stock shares on the May 31, 2013 acquisition date.
	On July 31, 2013, the Company acquired 100 percent of the outstanding common stock of NCBI and its wholly-owned subsidiary, North Cascades National Bank, a community bank based in Chelan, Washington. North Cascades Bank provides community banking services to individuals and businesses in central Washington, with banking offices located in Chelan, Wenatchee, East Wenatchee, Omak, Brewster, Twisp, Okanogan, Grand Coulee and Waterville, Washington. The acquisition expanded the Company’s market into central Washington and further diversified the Company’s loan, customer and deposit base due to the region’s solid economic base of agriculture, fruit processing and tourism. North Cascades Bank operates as a division of the Bank under the name “North Cascades Bank, division of Glacier Bank.” The NCBI acquisition was valued at $30,576,000 and resulted in the Company issuing 687,876 shares of its common stock and $13,833,000 in cash in exchange for all of NCBI’s outstanding common stock shares. The fair value of the Company’s common stock shares issued was determined on the basis of the closing market price of the Company’s common stock shares on the July 31, 2013 acquisition date.
	Note 22. Mergers and Acquisitions (continued)
	The assets and liabilities of Wheatland and NCBI were recorded on the Company’s consolidated statements of financial condition at their estimated fair values as of the May 31, 2013 and July 31, 2013 acquisition dates, respectively, and their results of operations have been included in the Company’s consolidated statements of operations since those dates. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisitions consists largely of the synergies and economies of scale expected from combining the operations of the Company, Wheatland and NCBI. None of the goodwill is deductible for income tax purposes as both acquisitions were accounted for as tax-free exchanges. The following table discloses the calculation of the fair value of consideration transferred, the total identifiable net assets acquired and the resulting goodwill relating to the Wheatland and NCBI acquisitions:
		Wheatland		NCBI
	(Dollars in thousands)	May 31,		July 31,	Total
		2013		2013
	Fair value of consideration transferred
	Fair value of Company shares issued, net of equity issuance costs	$	28,290	16,743	45,033
	Cash consideration for outstanding shares	11,025		13,833	24,858
	Total fair value of consideration transferred	39,315		30,576	69,891
	Recognized amounts of identifiable assets acquired and liabilities assumed
	Identifiable assets acquired
	Cash and cash equivalents	23,148		27,865	51,013
	Investment securities, available-for-sale	75,643		48,058	123,701
	Loans receivable	171,199		215,986	387,185
	Core deposit intangible	2,079		3,660	5,739
	Accrued income and other assets	15,063		24,262	39,325
	Total identifiable assets acquired	287,132		319,831	606,963
	Liabilities assumed
	Deposits	255,197		294,980	550,177
	FHLB advances and other borrowed funds	5,467		—	5,467
	Accrued expenses and other liabilities	562		4,472	5,034
	Total liabilities assumed	261,226		299,452	560,678
	Total identifiable net assets	25,906		20,379	46,285
	Goodwill recognized	$	13,409	10,197	23,606
	The fair value of the Wheatland and NCBI assets acquired includes loans with fair values of $171,199,000 and $215,986,000, respectively. The gross principal and contractual interest due under the Wheatland and NCBI contracts is $176,698,000 and $223,949,000, respectively, all of which is expected to be collectible.
	Core deposit intangible assets related to the Wheatland and NCBI acquisitions totaled $2,079,000 with an estimated life of 11 years and $3,660,000 with an estimated life of 10 years, respectively.
	The Company incurred $832,000 and $667,000, respectively, of Wheatland and NCBI third-party acquisition-related costs during the year ended December 31, 2013. The expenses are included in other expense in the Company’s consolidated statements of operations.
	Note 22. Mergers and Acquisitions (continued)
	Total income consisting of net interest income and non-interest income of the acquired operations of Wheatland was approximately $7,946,000 and net income was approximately $2,100,000 from May 31, 2013 to December 31, 2013. Total income consisting of net interest income and non-interest income of the acquired operations of NCBI was approximately $6,837,000 and net income was approximately $1,108,000 from July 31, 2013 to December 31, 2013. The following unaudited pro forma summary presents consolidated information of the Company as if the Wheatland and NCBI acquisitions had occurred on January 1, 2012:
		Year ended
	(Dollars in thousands)	December 31,		December 31,
		2013		2012
	Net interest income and non-interest income	$	339,236	334,317
	Net income	96,392		80,403

Subsequent_Event

Subsequent Event	12 Months Ended
	Dec. 31, 2013
Subsequent Events [Abstract]	'
Subsequent Event	'
	Note 23. Subsequent Event
	In connection with the ongoing monitoring of its investment securities portfolio, the Company reclassified obligations of state and local government securities with a fair value of approximately $484,583,000, inclusive of a net unrealized gain of $4,624,000, from AFS classification to HTM classification. The reclassification occurred on January 1, 2014 and changed the allocation of the Company’s entire investment securities portfolio from 100 percent AFS to approximately 85 percent AFS and 15 percent HTM. The future impact of this reclassification, if any, on the Company’s financial condition and results of operations will depend on interest rate environments and other factors which are not estimable at this time.

Nature_of_Operations_and_Summa1

Nature of Operations and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
General	'
	General
	Glacier Bancorp, Inc. (“Company”) is a Montana corporation headquartered in Kalispell, Montana. The Company provides a full range of banking services to individual and corporate customers in Montana, Idaho, Wyoming, Colorado, Utah and Washington through thirteen divisions of its wholly-owned bank subsidiary, Glacier Bank (“Bank”). The Company offers a wide range of banking products and services, including transaction and savings deposits, real estate, commercial, agriculture and consumer loans and mortgage origination services. The Company serves individuals, small to medium-sized businesses, community organizations and public entities.
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates.
	Material estimates that are particularly susceptible to significant change include: 1) the determination of the allowance for loan and lease losses (“ALLL” or “allowance”), 2) the valuations related to investments and real estate acquired in connection with foreclosures or in satisfaction of loans, and 3) the evaluation of goodwill impairment. For the determination of the ALLL and real estate valuation estimates, management obtains independent appraisals (new or updated) for significant items. Estimates relating to investment valuations are obtained from independent third parties. Estimates relating to the evaluation of goodwill for impairment are determined based on internal calculations using significant independent party inputs.
Principles of Consolidation	'
	Principles of Consolidation
	The consolidated financial statements of the Company include the parent holding company and the Bank. The Bank consists of thirteen bank divisions, a treasury division and an information technology division. The treasury division was formed on January 1, 2013 to efficiently manage the Bank’s investment security portfolio and wholesale borrowings. The information technology division was formed on January 1, 2013 and includes the Bank’s internal data processing and information technology expenses that previously were included with the parent holding company. Each of the bank divisions operate under separate names, management teams and directors. The Company considers the Bank to be its sole operating segment as the Bank 1) engages in similar bank business activity from which it earns revenues and incurs expenses, 2) the operating results of the Bank are regularly reviewed by the Chief Executive Officer (i.e., the chief operating decision maker) who makes decisions about resources to be allocated to the Bank, and 3) financial information is available for the Bank. All significant inter-company transactions have been eliminated in consolidation.
	On May 31, 2013, the Company completed its acquisition of Wheatland Bankshares, Inc. (“Wheatland”) and its wholly-owned subsidiary, First State Bank, a community bank based in Wheatland, Wyoming. On July 31, 2013, the Company completed its acquisition of North Cascades Bancshares, Inc. (“NCBI”) and its wholly-owned subsidiary, North Cascades National Bank, a community bank based in Chelan, Washington. Both transactions were accounted for using the acquisition method, and their results of operations have been included in the Company’s consolidated financial statements as of the acquisition dates.
	The Company formed GBCI Other Real Estate (“GORE”) to isolate certain bank foreclosed properties for legal protection and administrative purposes and the remaining properties are currently held for sale. GORE is included in the Bank operating segment due to its insignificant activity.
	The Company owns the following trust subsidiaries, each of which issued trust preferred securities as Tier 1 capital instruments: Glacier Capital Trust II, Glacier Capital Trust III, Glacier Capital Trust IV, Citizens (ID) Statutory Trust I, Bank of the San Juans Bancorporation Trust I, First Company Statutory Trust 2001 and First Company Statutory Trust 2003. The trust subsidiaries are not included in the Company’s consolidated financial statements.
Variable Interest Entities	'
	Variable Interest Entities
	A variable interest entity (“VIE”) exists when either 1) the entity’s total equity investment at risk is not sufficient to permit the entity to finance its activities without additional subordinated financial support from other parties, or 2) the entity has equity investors that cannot make significant decisions about the entity’s operations or that do not absorb their proportionate share of the expected losses or receive the expected returns of the entity. In addition, a VIE must be consolidated by the Company if it is deemed to be the primary beneficiary of the VIE, which is the party involved with the VIE that has the power to direct the VIE’s significant activities and will absorb a majority of the expected losses, receive a majority of the expected residual returns, or both. The Company’s VIEs are regularly monitored to determine if any reconsideration events have occurred that could cause the primary beneficiary status to change.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	The Company has equity investments in Certified Development Entities (“CDE”) which have received allocations of New Markets Tax Credits (“NMTC”). The Company also has equity investments in Low-Income Housing Tax Credit (“LIHTC”) partnerships. The CDEs and the LIHTC partnerships are VIEs. The underlying activities of the VIEs are community development projects designed primarily to promote community welfare, such as economic rehabilitation and development of low-income areas by providing housing, services, or jobs for residents. The maximum exposure to loss in the VIEs is the amount of equity invested and credit extended by the Company. However, the Company has credit protection in the form of indemnification agreements, guarantees, and collateral arrangements. The primary activities of the VIEs are recognized in commercial loans interest income, other non-interest income and other borrowed funds interest expense on the Company’s statements of operations. Such related cash flows are recognized in loans originated, principal collected on loans and change in other borrowed funds. The Company has evaluated the variable interests held by the Company in each CDE (NMTC) and LIHTC partnership investment and determined that the Company continues to be the primary beneficiary of such VIEs. As the primary beneficiary, the VIEs’ assets, liabilities, and results of operations are included in the Company’s consolidated financial statements.
	The following table summarizes the carrying amounts of the VIEs’ assets and liabilities included in the Company’s consolidated financial statements at December 31, 2013 and 2012:
		31-Dec-13			31-Dec-12
	(Dollars in thousands)	CDE (NMTC)		LIHTC	CDE (NMTC)	LIHTC
	Assets
	Loans receivable	$	36,039	—	35,480	—
	Premises and equipment, net	—		13,536	—	16,066
	Accrued interest receivable	117		—	117	—
	Other assets	843		153	1,114	143
	Total assets	$	36,999	13,689	36,711	16,209
	Liabilities
	Other borrowed funds	$	4,555	1,723	4,555	3,639
	Accrued interest payable	4		5	4	6
	Other liabilities	151		189	182	136
	Total liabilities	$	4,710	1,917	4,741	3,781
	Amounts presented in the table above are adjusted for intercompany eliminations. All assets presented can be used only to settle obligations of the consolidated VIEs and all liabilities presented consist of liabilities for which creditors and other beneficial interest holders therein have no recourse to the general credit of the Company.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	Cash and cash equivalents include cash on hand, cash held as demand deposits at various banks and regulatory agencies, interest bearing deposits, federal funds sold and liquid investments with original maturities of three months or less.
Investment Securities	'
	Investment Securities
	Debt securities for which the Company has the positive intent and ability to hold to maturity are classified as held-to-maturity (“HTM”) and are carried at amortized cost. Debt and equity securities held primarily for the purpose of selling in the near term are classified as trading securities and are reported at fair market value, with unrealized gains and losses included in income. Debt and equity securities not classified as HTM or trading are classified as available-for-sale (“AFS”) and are reported at fair value with unrealized gains and losses, net of income taxes, as a separate component of other comprehensive income. Premiums and discounts on investment securities are amortized or accreted into income using a method that approximates the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	The Company reviews and analyzes the various risks that may be present within the investment securities portfolio on an ongoing basis, including market risk and credit risk. Market risk is the risk to an entity’s financial condition resulting from adverse changes in the value of its holdings arising from movements in interest rates, foreign exchange rates, equity prices or commodity prices. The Company assesses the market risk of individual securities as well as the investment securities portfolio as a whole. Credit risk, broadly defined, is the risk that an issuer or counterparty will fail to perform on an obligation. A security is investment grade if the issuer has an adequate capacity to meet its commitment over the expected life of the investment, i.e., the risk of default is low and full and timely repayment of interest and principal is expected. To determine investment grade status for securities, the Company conducts due diligence of the creditworthiness of the issuer or counterparty prior to acquisition and ongoing thereafter consistent with the risk characteristics of the security and the overall risk of the investment securities portfolio. Credit quality due diligence takes into account the extent to which a security is guaranteed by the U.S. government and other agencies of the U.S. government. The depth of the due diligence is based on the complexity of the structure, the size of the security, and takes into account material positions and specific groups of securities or stratifications for analysis and review of similar risk positions. The due diligence includes consideration of payment performance, collateral adequacy, internal analyses, third party research and analytics, external credit ratings and default statistics.
	For additional information relating to investment securities, see Note 3.
Temporary versus Other-Than-Temporary Impairment	'
	Temporary versus Other-Than-Temporary Impairment
	The Company assesses individual securities in its investment securities portfolio for impairment at least on a quarterly basis, and more frequently when economic or market conditions warrant. An investment is impaired if the fair value of the security is less than its carrying value at the financial statement date. If impairment is determined to be other-than-temporary, an impairment loss is recognized by reducing the amortized cost for the credit loss portion of the impairment with a corresponding charge to earnings for a like amount.
	For fair value estimates provided by third party vendors, management also considered the models and methodology for appropriate consideration of both observable and unobservable inputs, including appropriately adjusted discount rates and credit spreads for securities with limited or inactive markets, and whether the quoted prices reflect orderly transactions. For certain securities, the Company obtained independent estimates of inputs, including cash flows, in supplement to third party vendor provided information. The Company also reviewed financial statements of select issuers, with follow up discussions with issuers’ management for clarification and verification of information relevant to the Company’s impairment analysis.
	In evaluating impaired securities for other-than-temporary impairment losses, management considers 1) the severity and duration of the impairment, 2) the credit ratings of the security, 3) the overall deal structure, including the Company’s position within the structure, the overall and near term financial performance of the issuer and underlying collateral, delinquencies, defaults, loss severities, recoveries, prepayments, cumulative loss projections, discounted cash flows and fair value estimates.
	In evaluating debt securities for other-than-temporary impairment losses, management assesses whether the Company intends to sell the security or if it is more-likely-than-not that the Company will be required to sell the debt security. In so doing, management considers contractual constraints, liquidity, capital, asset / liability management and securities portfolio objectives. If impairment is determined to be other-than-temporary and the Company does not intend to sell a debt security, and it is more-likely-than-not the Company will not be required to sell the security before recovery of its cost basis, it recognizes the credit component of an other-than-temporary impairment of a debt security in earnings and the remaining portion (noncredit portion) in other comprehensive income, net of tax. For held-to-maturity debt securities, the amount of an other-than-temporary impairment recorded in other comprehensive income for the noncredit portion of a previous other-than-temporary impairment is amortized prospectively, as an increase to the carrying amount of the security, over the remaining life of the security on the basis of the timing of future estimated cash flows of the security.
	If impairment is determined to be other-than-temporary and the Company intends to sell a debt security or it is more-likely-than-not the Company will be required to sell the security before recovery of its cost basis, it recognizes the entire amount of the other-than-temporary impairment in earnings.
	For debt securities with other-than-temporary impairment, the previous amortized cost basis less the other-than-temporary impairment recognized in earnings shall be the new amortized cost basis of the security. In subsequent periods, the Company accretes into interest income the difference between the new amortized cost basis and cash flows expected to be collected prospectively over the life of the debt security.
Loans Held for Sale	'
	Loans Held for Sale
	Loans held for sale generally consist of long-term, fixed rate, conforming, single-family residential real estate loans and are carried at the lower of cost or estimated fair value in the aggregate. Net unrealized losses, if any, are recognized by charges to non-interest income. A sale is recognized when the Company surrenders control of the loan and consideration, is received in exchange. A gain is recognized in non-interest income to the extent the sales price exceeds the carrying value of the sold loan.
Loans Receivable	'
	Loans Receivable
	Loans that are intended to be held-to-maturity are reported at the unpaid principal balance less net charge-offs and adjusted for deferred fees and costs on originated loans and unamortized premiums or discounts on acquired loans. Fees and costs on originated loans and premiums or discounts on acquired loans are deferred and subsequently amortized or accreted as a yield adjustment over the expected life of the loan utilizing the interest method. The objective of the interest method is to calculate periodic interest income at a constant effective yield. When a loan is paid off prior to maturity, the remaining fees and costs on originated loans and premiums or discounts on acquired loans are immediately recognized into interest income.
	The Company’s loan segments, which are based on the purpose of the loan, include residential real estate, commercial, and consumer loans. The Company’s loan classes, a further disaggregation of segments, include residential real estate loans (residential real estate segment), commercial real estate and other commercial loans (commercial segment), and home equity and other consumer loans (consumer segment).
	Loans that are thirty days or more past due based on payments received and applied to the loan are considered delinquent. Loans are designated non-accrual and the accrual of interest is discontinued when the collection of the contractual principal or interest is unlikely. A loan is typically placed on non-accrual when principal or interest is due and has remained unpaid for ninety days or more. When a loan is placed on non-accrual status, interest previously accrued but not collected is reversed against current period interest income. Subsequent payments on non-accrual loans are applied to the outstanding principal balance if doubt remains as to the ultimate collectability of the loan. Interest accruals are not resumed on partially charged-off impaired loans. For other loans on nonaccrual, interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of management, the loans are estimated to be fully collectible as to both principal and interest.
	The Company considers impaired loans to be the primary credit quality indicator for monitoring the credit quality of the loan portfolio. Loans are designated impaired when, based upon current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement and therefore, the Company has serious doubts as to the ability of such borrowers to fulfill the contractual obligation. Impaired loans include non-performing loans (i.e., non-accrual loans and accruing loans ninety days or more past due) and accruing loans under ninety days past due where it is probable payments will not be received according to the loan agreement (e.g., troubled debt restructuring). Interest income on accruing impaired loans is recognized using the interest method. The Company measures impairment on a loan-by-loan basis in the same manner for each class within the loan portfolio. An insignificant delay or shortfall in the amounts of payments would not cause a loan or lease to be considered impaired. The Company determines the significance of payment delays and shortfalls on a case-by-case basis, taking into consideration all of the facts and circumstances surrounding the loan and the borrower, including the length and reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest due.
	A restructured loan is considered a troubled debt restructuring (“TDR”) if the creditor, for economic or legal reasons related to the debtor’s financial difficulties, grants a concession to the debtor that it would not otherwise consider. A TDR loan is considered an impaired loan and a specific valuation allowance is established when the fair value of the collateral-dependent loan or present value of the loan’s expected future cash flows (discounted at the loan’s effective interest rate based on the original contractual rate) is lower than the carrying value of the impaired loan. The Company has made the following types of loan modifications, some of which were considered a TDR:
	•	Reduction of the stated interest rate for the remaining term of the debt;
	•	Extension of the maturity date(s) at a stated rate of interest lower than the current market rate for newly originated debt having similar risk characteristics; and
	•	Reduction of the face amount of the debt as stated in the debt agreements.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	The Company recognizes that while borrowers may experience deterioration in their financial condition, many continue to be creditworthy customers who have the willingness and capacity for debt repayment. In determining whether non-restructured or unimpaired loans issued to a single or related party group of borrowers should continue to accrue interest when the borrower has other loans that are impaired or are TDRs, the Company on a quarterly or more frequent basis performs an updated and comprehensive assessment of the willingness and capacity of the borrowers to timely and ultimately repay their total debt obligations, including contingent obligations. Such analysis takes into account current financial information about the borrowers and financially responsible guarantors, if any, including for example:
	•	analysis of global, i.e., aggregate debt service for total debt obligations;
	•	assessment of the value and security protection of collateral pledged using current market conditions and alternative market assumptions across a variety of potential future situations; and
	•	loan structures and related covenants.
	For additional information relating to loans, see Note 4.
Allowance for Loan and Lease Losses	'
	Allowance for Loan and Lease Losses
	Based upon management’s analysis of the Company’s loan portfolio, the balance of the ALLL is an estimate of probable credit losses known and inherent within the Bank’s loan portfolio as of the date of the consolidated financial statements. The ALLL is analyzed at the loan class level and is maintained within a range of estimated losses. Determining the adequacy of the ALLL involves a high degree of judgment and is inevitably imprecise as the risk of loss is difficult to quantify. The determination of the ALLL and the related provision for loan losses is a critical accounting estimate that involves management’s judgments about all known relevant internal and external environmental factors that affect loan losses. The balance of the ALLL is highly dependent upon management’s evaluations of borrowers’ current and prospective performance, appraisals and other variables affecting the quality of the loan portfolio. Individually significant loans and major lending areas are reviewed periodically to determine potential problems at an early date. Changes in management’s estimates and assumptions are reasonably possible and may have a material impact upon the Company’s consolidated financial statements, results of operations or capital.
	Risk characteristics considered in the ALLL analysis applicable to each loan class within the Company's loan portfolio are as follows:
	Residential Real Estate.  Residential real estate loans are secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class include a large number of borrowers, geographic dispersion of market areas and the loans are originated for relatively smaller amounts.
	Commercial Real Estate.  Commercial real estate loans typically involve larger principal amounts, and repayment of these loans is generally dependent on the successful operation of the property securing the loan and / or the business conducted on the property securing the loan.  Credit risk in these loans is impacted by the creditworthiness of a borrower, valuation of the property securing the loan and conditions within the local economies in the Company’s diverse, geographic market areas.
	Commercial.  Commercial loans consist of loans to commercial customers for use in financing working capital needs, equipment purchases and business expansions.  The loans in this category are repaid primarily from the cash flow of a borrower’s principal business operation.  Credit risk in these loans is driven by creditworthiness of a borrower and the economic conditions that impact the cash flow stability from business operations across the Company’s diverse, geographic market areas.
	Home Equity.  Home equity loans consist of junior lien mortgages and first and junior lien lines of credit (revolving open-end and amortizing closed-end) secured by owner-occupied 1-4 family residences.  Repayment of these loans is primarily dependent on the personal income and credit rating of the borrowers.  Credit risk in these loans is impacted by economic conditions within the Company’s market areas that affect the value of the residential property securing the loans and affect the borrowers' personal incomes.  Mitigating risk factors for this loan class are a large number of borrowers, geographic dispersion of market areas and the loans are originated for terms that range from 10 years to 15 years.
	Other Consumer.  The other consumer loan portfolio consists of various short-term loans such as automobile loans and loans for other personal purposes.  Repayment of these loans is primarily dependent on the personal income of the borrowers.  Credit risk is driven by consumer economic factors (such as unemployment and general economic conditions in the Company’s diverse, geographic market area) and the creditworthiness of a borrower.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	The ALLL consists of a specific valuation allowance component and a general valuation allowance component. The specific component relates to loans that are determined to be impaired and individually evaluated for impairment. The Company measures impairment on a loan-by-loan basis based on the present value of expected future cash flows discounted at the loan’s effective interest rate, except when it is determined that repayment of the loan is expected to be provided solely by the underlying collateral. For impairment based on expected future cash flows, the Company considers all information available as of a measurement date, including past events, current conditions, potential prepayments, and estimated cost to sell when such costs are expected to reduce the cash flows available to repay or otherwise satisfy the loan. For alternative ranges of cash flows, the likelihood of the possible outcomes is considered in determining the best estimate of expected future cash flows. The effective interest rate for a loan restructured in a TDR is based on the original contractual rate. For collateral-dependent loans and real estate loans for which foreclosure or a deed-in-lieu of foreclosure is probable, impairment is measured by the fair value of the collateral, less estimated cost to sell. The fair value of the collateral is determined primarily based upon appraisal or evaluation of the underlying real property value.
	The general valuation allowance component relates to probable credit losses inherent in the balance of the loan portfolio based on historical loss experience, adjusted for changes in trends and conditions of qualitative or environmental factors. The historical loss experience is based on the previous twelve quarters loss experience by loan class adjusted for risk characteristics in the existing loan portfolio. The same trends and conditions are evaluated for each class within the loan portfolio; however, the risk characteristics are weighted separately at the individual class level based on the Company’s judgment and experience.
	The changes in trends and conditions of certain items include the following:
	•	Changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses;
	•	Changes in international, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments;
	•	Changes in the nature and volume of the portfolio and in the terms of loans;
	•	Changes in experience, ability, and depth of lending management and other relevant staff;
	•	Changes in the volume and severity of past due and nonaccrual loans;
	•	Changes in the quality of the Company’s loan review system;
	•	Changes in the value of underlying collateral for collateral-dependent loans;
	•	The existence and effect of any concentrations of credit, and changes in the level of such concentrations; and
	•	The effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the Company’s existing portfolio.
	The ALLL is increased by provisions for loan losses which are charged to expense. The portions of loan balances determined by management to be uncollectible are charged-off as a reduction of the ALLL and recoveries of amounts previously charged-off are credited as an increase to the ALLL. The Company’s charge-off policy is consistent with bank regulatory standards. Consumer loans generally are charged off when the loan becomes over 120 days delinquent. Real estate acquired as a result of foreclosure or by deed-in-lieu of foreclosure is classified as real estate owned until such time as it is sold.
	At acquisition date, the assets and liabilities of acquired banks are recorded at their estimated fair values which results in no ALLL carried over from acquired banks. Subsequent to acquisition, an allowance will be recorded on the acquired loan portfolios for further credit deterioration, if any.
Premises and Equipment	'
	Premises and Equipment
	Premises and equipment are accounted for at cost less depreciation. Depreciation is computed on a straight-line method over the estimated useful lives or the term of the related lease. The estimated useful life for office buildings is 15 - 40 years and the estimated useful life for furniture, fixtures, and equipment is 3 - 10 years. Interest is capitalized for any significant building projects. For additional information relating to premises and equipment, see Note 5.
Leases	'
	Leases
	The Company leases certain land, premises and equipment from third parties under operating and capital leases. The lease payments for operating lease agreements are recognized on a straight-line basis. The present value of the future minimum rental payments for capital leases is recognized as an asset when the lease is formed. Lease improvements incurred at the inception of the lease are recorded as an asset and depreciated over the initial term of the lease and lease improvements incurred subsequently are depreciated over the remaining term of the lease. For additional information relating to leases, see Note 5.
Other Real Estate Owned	'
	Other Real Estate Owned
	Property acquired by foreclosure or deed-in-lieu of foreclosure is initially recorded at fair value, less estimated selling cost, at acquisition date (i.e., cost of the property). Fair value is determined as the amount that could be reasonably expected in a current sale between a willing buyer and a willing seller in an orderly transaction between market participants at the measurement date. Subsequent to the initial acquisition, if the fair value of the asset, less estimated selling cost, is less than the cost of the property, a loss is recognized in other expense and the asset carrying value is reduced. Gain or loss on disposition of other real estate owned (“OREO”) is recorded in non-interest income or non-interest expense, respectively. In determining the fair value of the properties on the date of transfer and any subsequent estimated losses of net realizable value, the fair value of other real estate acquired by foreclosure or deed-in-lieu of foreclosure is determined primarily based upon appraisal or evaluation of the underlying property value.
Long- Lived Assets	'
	Long-lived Assets
	Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. An asset is deemed impaired if the sum of the expected future cash flows is less than the carrying amount of the asset. If impaired, an impairment loss is recognized in other expense to reduce the carrying value of the asset to fair value. At December 31, 2013 and 2012, no long-lived assets were considered impaired.
Business Combinations and Intangible Assets	'
	Business Combinations and Intangible Assets
	Acquisition accounting requires the total purchase price to be allocated to the estimated fair values of assets acquired and liabilities assumed, including certain intangible assets. Goodwill is recorded if the purchase price exceeds the net fair value of assets acquired and a bargain purchase gain is recorded in other income if the net fair value of assets acquired exceeds the purchase price.
	Adjustment of the allocated purchase price may be related to fair value estimates for which all information has not been obtained of the acquired entity known or discovered during the allocation period, the period of time required to identify and measure the fair values of the assets and liabilities acquired in the business combination. The allocation period is generally limited to one year following consummation of a business combination.
	Core deposit intangible represents the intangible value of depositor relationships resulting from deposit liabilities assumed in acquisitions and is amortized using an accelerated method based on an estimated runoff of the related deposits. The core deposit intangible is evaluated for impairment and recoverability whenever events or changes in circumstances indicate that its carrying amount may not be recoverable, with any changes in estimated useful life accounted for prospectively over the revised remaining life. For additional information relating to core deposit intangibles, see Note 6.
	The Company tests goodwill for impairment at the reporting unit level annually during the third quarter. The Company has identified that each of the bank divisions are reporting units (i.e., components of the Glacier Bank operating segment) given that each division has a separate management team that regularly reviews its respective division financial information; however, the reporting units are aggregated into a single reporting unit due to the reporting units having similar economic characteristics.
	The goodwill of a reporting unit is tested for impairment between annual tests if an event occurs or circumstances change that would more-likely-than not reduce the fair value of a reporting units below its carrying amount. Examples of events and circumstances that could trigger the need for interim impairment testing include:
	•	A significant change in legal factors or in the business climate;
	•	An adverse action or assessment by a regulator;
	•	Unanticipated competition;
	•	A loss of key personnel;
	•	A more-likely-than-not expectation that a reporting unit or a significant portion of a reporting unit will be sold or otherwise disposed of; and
	•	The testing for recoverability of a significant asset group within a reporting unit.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	For the goodwill impairment assessment, the Company has the option, prior to the two-step process, to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of a reporting unit is less than its carrying value. The Company opted to bypass the qualitative assessment for its 2013 and 2012 annual goodwill impairment testing and proceed directly to the two-step goodwill impairment test. The goodwill impairment two-step process requires the Company to make assumptions and judgments regarding fair value. In the first step, the Company calculates an implied fair value based on a control premium analysis. If the implied fair value is less than the carrying value, the second step is completed to compute the impairment amount, if any, by determining the “implied fair value” of goodwill. This determination requires the allocation of the estimated fair value of the reporting units to the assets and liabilities of the reporting units. Any remaining unallocated fair value represents the “implied fair value” of goodwill, which is compared to the corresponding carrying value of goodwill to compute impairment, if any.
	For additional information relating to goodwill, see Note 6.
Non-Marketable Equity Securities	'
	Non-Marketable Equity Securities
	Non-marketable equity securities primarily consists of Federal Home Loan Bank (“FHLB”) stock. FHLB stock is restricted because such stock may only be sold to FHLB at its par value. Due to restrictive terms, and the lack of a readily determinable market value, FHLB stock is carried at cost. The investments in FHLB stock are required investments related to the Company’s borrowings from FHLB. FHLB obtains its funding primarily through issuance of consolidated obligations of the FHLB system. The U.S. government does not guarantee these obligations, and each of the regional FHLBs are jointly and severally liable for repayment of each other’s debt.
Derivatives and Hedging Activities	'
	Derivatives and Hedging Activities
	For asset and liability management purposes, the Company has entered into interest rate swap agreements to hedge against changes in forecasted cash flows due to interest rate exposures. The interest rate swaps are recognized as assets or liabilities on the Company’s statements of financial condition and measured at fair value. Fair value estimates are obtained from third parties and are based on pricing models. The Company does not enter into interest rate swap agreements for trading or speculative purposes.
	The Company takes into account the impact of bilateral collateral and master netting agreements that allows the Company to settle all interest rate swap agreements held with a single counterparty on a net basis, and to offset the net interest rate swap derivative position with the related collateral when recognizing interest rate swap derivative assets and liabilities.
	Interest rate swaps are contracts in which a series of interest payments are exchanged over a prescribed period. The notional amount upon which the interest payments are based is not exchanged. The swap agreements are derivative instruments and convert a portion of the Company’s forecasted variable rate debt to a fixed rate (i.e., cash flow hedge). The effective portion of the gain or loss on the cash flow hedging instruments is initially reported as a component of other comprehensive income and subsequently reclassified into earnings in the same period during which the transaction affects earnings. The ineffective portion of the gain or loss on derivative instruments, if any, is recognized in earnings. The Company currently has cash flow hedges of which no portion is ineffective.
	Interest rate derivative financial instruments receive hedge accounting treatment only if they are designated as a hedge and are expected to be, and are, effective in substantially reducing interest rate risk arising from the assets and liabilities identified as exposing the Company to risk. Derivative financial instruments that do not meet specified hedging criteria are recorded at fair value with changes in fair value recorded in income. The Company’s interest rate swaps are considered highly effective and currently meet the hedging accounting criteria.
	Cash flows resulting from the interest rate derivative financial instruments that are accounted for as hedges of assets and liabilities are classified in the Company’s cash flow statement in the same category as the cash flows of the items being hedged. For additional information relating to interest rate swap agreements, see Note 11.
Comprehensive Income	'
	Comprehensive Income
	Comprehensive income consists of net income and other comprehensive income. Other comprehensive income includes unrealized gains and losses, net of tax effect, on available-for-sale securities and unrealized gains and losses, net of tax effect, on derivatives used for cash flow hedges.
Advertising and Promotion	'
	Advertising and Promotion
	Advertising and promotion costs are recognized in the period incurred.
Income Taxes	'
	Income Taxes
	The Company’s income tax expense consists of current and deferred income tax expense. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of enacted tax law to earnings or losses. Deferred income tax expense results from changes in deferred assets and liabilities between periods.
	Deferred tax assets and liabilities are recognized for estimated future income tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases. The effect on deferred tax assets and liabilities of a change in income tax rates is recognized in income in the period that includes the enactment date.
	Deferred tax assets are reduced by a valuation allowance, if based on the weight of available evidence, it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The term more-likely-than-not means a likelihood of more than fifty percent. The recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to the Company’s judgment. In assessing the need for a valuation allowance, the Company considers both positive and negative evidence. For additional information relating to income taxes, see Note 14.
Earnings Per Share	'
	Earnings Per Share
	Basic earnings per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period presented. Diluted earnings per share is computed by including the net increase in shares as if dilutive outstanding stock options were exercised, using the treasury stock method. For additional information relating to earnings per share, see Note 15.
Stock-based Compensation	'
	Stock-based Compensation
	Stock-based compensation awards granted, comprised of stock options and restricted stock awards, are valued at fair value and compensation cost is recognized on a straight-line basis, net of estimated forfeitures, over the requisite service period of each award. For additional information relating to stock-based compensation, see Note 17.
Reclassifications	'
	Reclassifications
	Certain reclassifications have been made to the 2012 and 2011 financial statements to conform to the 2013 presentation.
Impact of Recent Authoritative Accounting Guidance	'
	Impact of Recent Authoritative Accounting Guidance
	The Accounting Standards Codification™ (“ASC”) is the Financial Accounting Standards Board’s (“FASB”) officially recognized source of authoritative GAAP applicable to all public and non-public non-governmental entities. Rules and interpretive releases of the Securities and Exchange Commission (“SEC”) under the authority of the federal securities laws are also sources of authoritative GAAP for the Company as an SEC registrant. All other accounting literature is non-authoritative.
	In January 2014, FASB amended FASB ASC Subtopic 310-40, Receivables - Troubled Debt Restructurings by Creditors. The amendment clarifies that an in substance repossession foreclosure occurs when a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either 1) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or 2) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. Additionally, the amendment requires interim and annual disclosure of both 1) the amount of foreclosed residential real estate property held by the creditor and 2) the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure according to local requirements of the applicable jurisdiction. The amendment is effective for public business entities for interim and annual periods beginning after December 15, 2014. An entity can elect to adopt the amendments using either a modified retrospective transition method or a prospective transition method as defined in the amendment. The Company is currently evaluating the impact of the adoption of this amendment, but does not expect it to have a material effect on the Company’s financial position or results of operations.
	In January 2014, FASB amended FASB ASC Topic 323, Investments - Equity Method and Joint Ventures. The amendments permit entities to make an accounting policy election for their investments in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportional amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense. The amendments should be applied retrospectively to all periods presented and are effective for public business entities for annual periods and interim periods within those annual periods, beginning after December 15, 2014. The Company is currently evaluating the impact of the adoption of the amendments, but does not expect them to have a material effect on the Company’s financial position or results of operations.
	Note 1. Nature of Operations and Summary of Significant Accounting Policies (continued)
	In June 2011, FASB amended FASB ASC Topic 220, Comprehensive Income. The amendment provides an entity the option to present the total of comprehensive income, the components of net income, and the components of other comprehensive income either in a single continuous statement or in two separate but consecutive statements. Accounting Standards Update (“ASU”) No. 2011-12, Comprehensive Income (Topic 220) deferred the specific requirement of the amendment to present items that are reclassified from accumulated other comprehensive income to net income separately with their respective components of net income and other comprehensive income. The amendments were effective retrospectively during interim and annual periods beginning after December 15, 2011. ASU No. 2013-2, Comprehensive Income (Topic 220) reversed the deferment of ASU 2011-12 and will be effective prospectively for reporting periods beginning after December 15, 2012 and early adoption is permitted. The Company early adopted ASU No. 2013-2 as of December 31, 2012. The Company has evaluated the impact of the adoption of these amendments and determined there was not a material effect on the Company’s financial position or results of operations.

Nature_of_Operations_and_Summa2

Nature of Operations and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Carrying amounts of VIE's assets and liabilities	'
		31-Dec-13			31-Dec-12
	(Dollars in thousands)	CDE (NMTC)		LIHTC	CDE (NMTC)	LIHTC
	Assets
	Loans receivable	$	36,039	—	35,480	—
	Premises and equipment, net	—		13,536	—	16,066
	Accrued interest receivable	117		—	117	—
	Other assets	843		153	1,114	143
	Total assets	$	36,999	13,689	36,711	16,209
	Liabilities
	Other borrowed funds	$	4,555	1,723	4,555	3,639
	Accrued interest payable	4		5	4	6
	Other liabilities	151		189	182	136
	Total liabilities	$	4,710	1,917	4,741	3,781

Investment_Securities_Availabl1

Investment Securities, Available-for-Sale (Tables)	12 Months Ended
	Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]	'
Comparison of amortized cost and estimated fair value of investment securities designated as available-for-sale	'
		31-Dec-13
		Weighted			Amortized			Gross Unrealized				Fair
	(Dollars in thousands)	Yield			Cost			Gains		Losses		Value
	U.S. government sponsored enterprises
	Maturing after one year through five years	2.32	%		$	10,405		187		—		10,592
	Maturing after five years through ten years	2	%		36			—		—		36
		2.32	%		10,441			187		—		10,628
	State and local governments
	Maturing within one year	2.22	%		5,964			57		—		6,021
	Maturing after one year through five years	2.06	%		174,826			3,486		(448	)	177,864
	Maturing after five years through ten years	3.21	%		58,835			831		(1,040	)	58,626
	Maturing after ten years	4.41	%		1,137,722			27,247		(22,402	)	1,142,567
		4.06	%		1,377,347			31,621		(23,890	)	1,385,078
	Corporate bonds
	Maturing within one year	2.17	%		91,687			719		—		92,406
	Maturing after one year through five years	2.09	%		341,799			3,203		(1,676	)	343,326
	Maturing after five years through ten years	2.23	%		6,851			—		(82	)	6,769
		2.11	%		440,337			3,922		(1,758	)	442,501
	Residential mortgage-backed securities	2.48	%		1,380,816			14,071		(10,265	)	1,384,622
	Total investment securities	3.1	%		$	3,208,941		49,801		(35,913	)	3,222,829
	Note 3. Investment Securities, Available-for-Sale (continued)
		31-Dec-12
		Weighted			Amortized			Gross Unrealized				Fair
	(Dollars in thousands)	Yield			Cost			Gains		Losses		Value
	U.S. government and federal agency
	Maturing within one year	1.62	%		$	201		1		—		202
	U.S. government sponsored enterprises
	Maturing after one year through five years	2.3	%		17,064			371		—		17,435
	Maturing after five years through ten years	2.03	%		44			1		—		45
		2.29	%		17,108			372		—		17,480
	State and local governments
	Maturing within one year	2.01	%		4,288			28		(2	)	4,314
	Maturing after one year through five years	2.11	%		149,497			4,142		(142	)	153,497
	Maturing after five years through ten years	2.95	%		38,346			1,102		(99	)	39,349
	Maturing after ten years	4.7	%		935,897			82,823		(1,362	)	1,017,358
		4.29	%		1,128,028			88,095		(1,605	)	1,214,518
	Corporate bonds
	Maturing within one year	1.73	%		18,412			51		—		18,463
	Maturing after one year through five years	2.22	%		250,027			4,018		(238	)	253,807
	Maturing after five years through ten years	2.23	%		16,144			381		—		16,525
		2.19	%		284,583			4,450		(238	)	288,795
	Collateralized debt obligations
	Maturing after ten years	8.03	%		1,708			—		—		1,708
	Residential mortgage-backed securities	1.95	%		2,156,049			8,860		(4,607	)	2,160,302
	Total investment securities	2.71	%		$	3,587,677		101,778		(6,450	)	3,683,005
Gain or Loss on sale of Investments	'
		Years ended
	(Dollars in thousands)	December 31,				December 31,		December 31,
		2013				2012		2011
	Gross proceeds	$	181,971			—		18,916
	Less amortized cost	(182,270		)		—		(18,570	)
	Net (loss) gain on sale of investments	$	(299	)		—		346
	Gross gain on sale of investments	$	3,723			—		1,048
	Gross loss on sale of investments	(4,022		)		—		(702	)
	Net (loss) gain on sale of investments	$	(299	)		—		346
Summary of investments with an unrealized loss position	'
		31-Dec-13
		Less than 12 Months						12 Months or More				Total
	(Dollars in thousands)	Fair				Unrealized		Fair		Unrealized		Fair	Unrealized
		Value				Loss		Value		Loss		Value	Loss
	U.S. government sponsored enterprises	$	3			—		—		—		3	—
	State and local governments	408,812				(17,838	)	74,161		(6,052	)	482,973	(23,890	)
	Corporate bonds	129,515				(1,672	)	1,702		(86	)	131,217	(1,758	)
	Residential mortgage-backed securities	457,611				(10,226	)	1,993		(39	)	459,604	(10,265	)
	Total temporarily impaired securities	$	995,941			(29,736	)	77,856		(6,177	)	1,073,797	(35,913	)
		31-Dec-12
		Less than 12 Months						12 Months or More				Total
	(Dollars in thousands)	Fair				Unrealized		Fair		Unrealized		Fair	Unrealized
		Value				Loss		Value		Loss		Value	Loss
	State and local governments	$	102,896			(1,531	)	4,533		(74	)	107,429	(1,605	)
	Corporate bonds	41,856				(238	)	—		—		41,856	(238	)
	Residential mortgage-backed securities	955,235				(4,041	)	62,905		(566	)	1,018,140	(4,607	)
	Total temporarily impaired securities	$	1,099,987			(5,810	)	67,438		(640	)	1,167,425	(6,450	)

Loans_Receivable_Net_Tables

Loans Receivable, Net (Tables)	12 Months Ended
	Dec. 31, 2013
Receivables [Abstract]	'
Summary of activity in the ALLL on a portfolio class basis	'
		Year ended December 31, 2013
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Balance at beginning of period	$	130,854		15,482		74,398		21,567		10,659		8,748
	Provision for loan losses	6,887			(921	)	(3,670	)	10,271		868		339
	Charge-offs	(13,643		)	(793	)	(3,736	)	(4,671	)	(2,594	)	(1,849	)
	Recoveries	6,253			299		3,340		1,463		366		785
	Balance at end of period	$	130,351		14,067		70,332		28,630		9,299		8,023
		Year ended December 31, 2012
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Balance at beginning of period	$	137,516		17,227		76,920		20,833		13,616		8,920
	Provision for loan losses	21,525			2,879		11,012		4,690		324		2,620
	Charge-offs	(34,672		)	(5,267	)	(16,339	)	(5,239	)	(4,369	)	(3,458	)
	Recoveries	6,485			643		2,805		1,283		1,088		666
	Balance at end of period	$	130,854		15,482		74,398		21,567		10,659		8,748
		Year ended December 31, 2011
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Balance at beginning of period	$	137,107		20,957		76,147		19,932		13,334		6,737
	Provision for loan losses	64,500			1,455		39,563		10,709		4,450		8,323
	Charge-offs	(69,366		)	(5,671	)	(42,042	)	(10,386	)	(4,644	)	(6,623	)
	Recoveries	5,275			486		3,252		578		476		483
	Balance at end of period	$	137,516		17,227		76,920		20,833		13,616		8,920
Summary of Loans and ALLL on a portfolio class basis	'
		31-Dec-13
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Individually evaluated for impairment	$	11,949		990		3,763		6,155		265		776
	Collectively evaluated for impairment	118,402			13,077		66,569		22,475		9,034		7,247
	Total allowance for loan and lease losses	$	130,351		14,067		70,332		28,630		9,299		8,023
	Loans receivable
	Individually evaluated for impairment	$	199,680		24,070		119,526		41,504		9,039		5,541
	Collectively evaluated for impairment	3,863,158			553,519		1,929,721		810,532		357,426		211,960
	Total loans receivable	$	4,062,838		577,589		2,049,247		852,036		366,465		217,501
		31-Dec-12
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Allowance for loan and lease losses
	Individually evaluated for impairment	$	15,534		1,680		7,716		3,859		870		1,409
	Collectively evaluated for impairment	115,320			13,802		66,682		17,708		9,789		7,339
	Total allowance for loan and lease losses	$	130,854		15,482		74,398		21,567		10,659		8,748
	Loans receivable
	Individually evaluated for impairment	$	201,735		25,862		125,282		33,593		11,074		5,924
	Collectively evaluated for impairment	3,195,690			490,605		1,530,226		589,804		392,851		192,204
	Total loans receivable	$	3,397,425		516,467		1,655,508		623,397		403,925		198,128
Summary of the impaired loans on a portfolio class basis	'
		At or for the Year ended December 31, 2013
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Loans with a specific valuation allowance
	Recorded balance	$	61,503		7,233		23,917		27,015		886		2,452
	Unpaid principal balance	63,406			7,394		25,331		27,238		949		2,494
	Specific valuation allowance	11,949			990		3,763		6,155		265		776
	Average balance	59,823			7,237		26,105		22,460		767		3,254
	Loans without a specific valuation allowance
	Recorded balance	$	138,177		16,837		95,609		14,489		8,153		3,089
	Unpaid principal balance	169,082			18,033		119,017		19,156		9,631		3,245
	Average balance	139,129			18,103		95,808		14,106		8,844		2,268
	Totals
	Recorded balance	$	199,680		24,070		119,526		41,504		9,039		5,541
	Unpaid principal balance	232,488			25,427		144,348		46,394		10,580		5,739
	Specific valuation allowance	11,949			990		3,763		6,155		265		776
	Average balance	198,952			25,340		121,913		36,566		9,611		5,522
		At or for the Year ended December 31, 2012
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Loans with a specific valuation allowance
	Recorded balance	$	62,759		7,334		29,595		21,205		1,354		3,271
	Unpaid principal balance	70,261			7,459		36,887		21,278		1,362		3,275
	Specific valuation allowance	15,534			1,680		7,716		3,859		870		1,409
	Average balance	76,656			12,797		36,164		22,665		1,390		3,640
	Loans without a specific valuation allowance
	Recorded balance	$	138,976		18,528		95,687		12,388		9,720		2,653
	Unpaid principal balance	149,412			19,613		102,798		14,318		9,965		2,718
	Average balance	162,505			16,034		111,554		19,733		11,993		3,191
	Totals
	Recorded balance	$	201,735		25,862		125,282		33,593		11,074		5,924
	Unpaid principal balance	219,673			27,072		139,685		35,596		11,327		5,993
	Specific valuation allowance	15,534			1,680		7,716		3,859		870		1,409
	Average balance	239,161			28,831		147,718		42,398		13,383		6,831
Loan portfolio aging analysis on a portfolio class basis	'
		31-Dec-13
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Accruing loans 30-59 days past due	$	25,761		10,367		7,016		3,673		2,432		2,273
	Accruing loans 60-89 days past due	6,355			1,055		2,709		1,421		668		502
	Accruing loans 90 days or more past due	604			429		—		160		5		10
	Non-accrual loans	81,956			10,702		51,438		10,139		7,950		1,727
	Total past due and non-accrual loans	114,676			22,553		61,163		15,393		11,055		4,512
	Current loans receivable	3,948,162			555,036		1,988,084		836,643		355,410		212,989
	Total loans receivable	$	4,062,838		577,589		2,049,247		852,036		366,465		217,501
		December 31, 2012
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Accruing loans 30-59 days past due	$	17,454		3,897		7,424		2,020		2,872		1,241
	Accruing loans 60-89 days past due	9,643			1,870		3,745		645		2,980		403
	Accruing loans 90 days or more past due	1,479			451		594		197		188		49
	Non-accrual loans	96,933			14,237		55,687		13,200		11,241		2,568
	Total past due and non-accrual loans	125,509			20,455		67,450		16,062		17,281		4,261
	Current loans receivable	3,271,916			496,012		1,588,058		607,335		386,644		193,867
	Total loans receivable	$	3,397,425		516,467		1,655,508		623,397		403,925		198,128
Summary of TDRs on a portfolio class basis	'
		Year ended December 31, 2013
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Troubled debt restructurings
	Number of loans	63			9		21		23		2		8
	Pre-modification recorded balance	$	29,046		1,907		20,334		6,087		147		571
	Post-modification recorded balance	$	29,359		2,293		20,334		6,087		147		498
	Troubled debt restructurings that subsequently defaulted
	Number of loans	5			1		1		3		—		—
	Recorded balance	$	849		265		79		505		—		—
	Note 4. Loans Receivable, Net (continued)
		Year ended December 31, 2012
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Troubled debt restructurings
	Number of loans	198			11		85		75		10		17
	Pre-modification recorded balance	$	90,747		2,280		57,382		28,639		1,358		1,088
	Post-modification recorded balance	$	89,558		2,281		56,120		28,711		1,358		1,088
	Troubled debt restructurings that subsequently defaulted
	Number of loans	14			—		4		6		3		1
	Recorded balance	$	8,304		—		6,192		1,753		301		58
		Year ended December 31, 2011
	(Dollars in thousands)	Total			Residential		Commercial		Other		Home		Other
					Real Estate		Real Estate		Commercial		Equity		Consumer
	Troubled debt restructurings
	Number of loans	338			20		120		149		22		27
	Pre-modification recorded balance	$	158,295		13,500		109,593		20,446		9,198		5,558
	Post-modification recorded balance	$	155,827		13,452		107,778		20,434		9,200		4,963
	Troubled debt restructurings that subsequently defaulted
	Number of loans	66			4		29		22		7		4
	Recorded balance	$	41,236		2,291		32,615		2,718		3,202		410

Premises_and_Equipment_Tables

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment [Abstract]	'
Premises and equipment, net of accumulated depreciation	'
	(Dollars in thousands)	31-Dec-13			31-Dec-12
	Land	$	27,260		25,027
	Office buildings and construction in progress	159,391			153,340
	Furniture, fixtures and equipment	66,375			63,467
	Leasehold improvements	7,589			7,393
	Accumulated depreciation	(92,944		)	(90,238	)
	Net premises and equipment	$	167,671		158,989
Future Minimum Rental Commitments required under Operating and Capital Leases	'
	(Dollars in thousands)	Capital			Operating		Total
		Leases			Leases
	Years ending December 31,
	2014	$	828		2,297		3,125
	2015	195			2,120		2,315
	2016	197			1,879		2,076
	2017	200			1,577		1,777
	2018	203			1,375		1,578
	Thereafter	546			2,900		3,446
	Total minimum lease payments	2,169			12,148		14,317
	Less: Amount representing interest	479
	Present value of minimum lease payments	1,690
	Less: Current portion of obligations under capital leases	708
	Long-term portion of obligations under capital leases	$	982

Other_Intangible_Assets_and_Go1

Other Intangible Assets and Goodwill (Tables)	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Core deposit intangibles	'
		At or for the Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Gross carrying value	$	27,857		22,404		28,248
	Accumulated amortization	(18,345		)	(16,230	)	(19,964	)
	Net carrying value	$	9,512		6,174		8,284
	Aggregate amortization expense	$	2,401		2,110		2,473
	Weighted-average amortization period
	(Period in years)	9.5
	Estimated amortization expense for the years ending December 31,
	2014	$	2,650
	2015	2,198
	2016	1,700
	2017	828
	2018	430
Changes in the carrying value of goodwill	'
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Net carrying value at beginning of period	$	106,100		106,100		146,259
	Acquisitions	23,606			—		—
	Impairment charge	—			—		(40,159	)
	Net carrying value at end of period	$	129,706		106,100		106,100
Gross carrying value of goodwill and the accumulated impairment charge	'
	(Dollars in thousands)	December 31,			December 31,
		2013			2012
	Gross carrying value	$	169,865		146,259
	Accumulated impairment charge	(40,159		)	(40,159	)
	Net carrying value	$	129,706		106,100

Deposits_Tables

Deposits (Tables)	12 Months Ended
	Dec. 31, 2013
Deposits [Abstract]	'
Summary of deposits	'
	(Dollars in thousands)	December 31, 2013				December 31, 2012
	Non-interest bearing deposits	$	1,374,419	24.6	%	1,191,933	22.2	%
	NOW accounts	1,113,878		20	%	988,984	18.4	%
	Savings accounts	600,998		10.8	%	478,809	8.9	%
	Money market deposit accounts	1,168,918		20.9	%	931,370	17.4	%
	Certificate accounts	1,116,622		20	%	1,015,491	19	%
	Wholesale deposits 1	205,132		3.7	%	757,874	14.1	%
	Total interest bearing deposits	4,205,548		75.4	%	4,172,528	77.8	%
	Total deposits	$	5,579,967	100	%	5,364,461	100	%
	Deposits with a balance of $100,000 and greater
	Demand deposits	$	2,685,577			2,361,528
	Certificate accounts	661,924				1,044,488
	Total balances of $100,000 and greater	$	3,347,501			3,406,016
Scheduled maturities of time deposits	'
	(Dollars in thousands)	Amount
	Years ending December 31,
	2014	$	864,633
	2015	164,104
	2016	79,425
	2017	33,975
	2018	19,244
	Thereafter	7,220
		$	1,168,601

Securities_Sold_Under_Agreemen1

Securities Sold Under Agreements to Repurchase (Tables)	12 Months Ended
	Dec. 31, 2013
Disclosure of Repurchase Agreements [Abstract]	'
Summary of repurchase agreements	'
		December 31, 2013
	(Dollars in thousands)	Repurchase		Weighted-		Amortized		Fair
		Amount		Average		Cost of		Value of
				Fixed Rate		Underlying		Underlying
						Assets		Assets
	Overnight	$	303,709	0.28	%	$	304,263	312,856
	Maturing within 30 days	9,685		0.32	%	11,095		11,301
		$	313,394	0.28	%	$	315,358	324,157
		December 31, 2012
	(Dollars in thousands)	Repurchase		Weighted-		Amortized		Fair
		Amount		Average		Cost of		Value of
				Fixed Rate		Underlying		Underlying
						Assets		Assets
	Overnight	$	285,349	0.32	%	$	287,597	293,958
	Maturing within 30 days	4,159		0.5	%	4,228		4,306
		$	289,508	0.32	%	$	291,825	298,264

Borrowings_Tables

Borrowings (Tables)	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
FHLB Advances	'
		December 31, 2013				December 31, 2012
	(Dollars in thousands)	Amount		Weighted		Amount		Weighted
				Rate				Rate
	Maturing within one year	$	559,084	0.24	%	$	720,000	0.28	%
	Maturing one year through two years	77,979		3.36	%	—		—	%
	Maturing two years through three years	45,042		2.99	%	75,000		3.48	%
	Maturing three years through four years	—		—	%	45,000		2.99	%
	Maturing four years through five years	20,250		2.83	%	—		—	%
	Thereafter	137,827		3.12	%	157,013		3.07	%
	Total	$	840,182	1.21	%	$	997,013	1.09	%
FHLB Put Options	'
	(Dollars in thousands)	Amount		Interest
				Rate
	Maturing during years ending December 31,
	2015	$	75,000	3.16% - 3.64%
	2016	45,000		2.93% - 3.05%
	2018	20,000		2.73% - 2.85%
	2021	135,000		2.88% - 3.43%
		$	275,000

Subordinated_Debentures_Tables

Subordinated Debentures (Tables)	12 Months Ended
	Dec. 31, 2013
Subordinate Debenture [Abstract]	'
Terms of Subordinated Debentures	'
		31-Dec-13				Variable Rate Structure	Maturity Date
	(Dollars in thousands)	Balance		Rate
	First Company Statutory Trust 2001	$	3,018	3.537	%	3 mo LIBOR plus 3.30	7/31/31
	First Company Statutory Trust 2003	2,227		3.496	%	3 mo LIBOR plus 3.25	3/26/33
	Glacier Capital Trust II	46,393		2.994	%	3 mo LIBOR plus 2.75	4/7/34
	Citizens (ID) Statutory Trust I	5,155		2.894	%	3 mo LIBOR plus 2.65	6/17/34
	Glacier Capital Trust III	36,083		1.533	%	3 mo LIBOR plus 1.29	4/7/36
	Glacier Capital Trust IV	30,928		1.813	%	3 mo LIBOR plus 1.57	9/15/36
	Bank of the San Juans Bancorporation Trust I	1,758		2.058	%	3 mo LIBOR plus 1.82	3/1/37
		$	125,562

Derivatives_and_Hedging_Activi1

Derivatives and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Summary of Interest Rate Derivative Financial Instruments	'
	(Dollars in thousands)	Forecasted		Variable		Fixed		Term 2
		Notional  Amount		Interest Rate 1		Interest Rate 1
	Interest rate swap	$	160,000	3 month LIBOR		3.378	%	Oct. 21, 2014 - Oct. 21, 2021
	Interest rate swap	100,000		3 month LIBOR		2.498	%	Nov 30, 2015 - Nov. 30, 2022
	__________
	1 The Company pays the fixed interest rate and the counterparty pays the Company the variable interest rate.
	2 No cash will be exchanged prior to the term.
Offsetting Assets	'
		December 31, 2013							December 31, 2012
	(Dollars in thousands)	Gross Amounts of Recognized Assets		Gross Amounts Offset in the Statements of Financial Position			Net Amounts of Assets Presented in the Statements of Financial Position		Gross Amounts of Recognized Assets	Gross Amounts Offset in the Statements of Financial Position	Net Amounts of Assets Presented in the Statements of Financial Position
	Interest rate swaps	$	6,844	(4,948	)		1,896		—	—	—
Offsetting Liabilities	'
		December 31, 2013							December 31, 2012
	(Dollars in thousands)	Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Statements of Financial Position			Net Amounts of Liabilities Presented in the Statements of Financial Position		Gross Amounts of Recognized Liabilities	Gross Amounts Offset in the Statements of Financial Position	Net Amounts of Liabilities Presented in the Statements of Financial Position
	Interest rate swaps	$	4,948	(4,948	)		—		16,832	—	16,832

Regulatory_Capital_Tables

Regulatory Capital (Tables)	12 Months Ended
	Dec. 31, 2013
Banking and Thrift [Abstract]	'
Capital adequacy guidelines and compliance	'
		31-Dec-13
		Actual				Minimum Capital				Well Capitalized
						Requirement				Requirement
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	Total capital (to risk-weighted assets)
	Consolidated	$	1,005,980	18.97	%	$	424,322	8	%	$	530,402	10	%
	Glacier Bank	948,618		17.93	%	423,235		8	%	529,044		10	%
	Tier 1 capital (to risk-weighted assets)
	Consolidated	$	938,887	17.7	%	$	212,161	4	%	$	318,241	6	%
	Glacier Bank	881,692		16.67	%	211,618		4	%	317,426		6	%
	Tier 1 capital (to average assets)
	Consolidated	$	938,887	12.11	%	$	310,082	4	%	N/A		N/A
	Glacier Bank	881,692		11.44	%	308,281		4	%	$	385,351	5	%
	Note 12. Regulatory Capital (continued)
		31-Dec-12
		Actual				Minimum Capital				Well Capitalized
						Requirement				Requirement
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	Total capital (to risk-weighted assets)
	Consolidated	$	923,574	20.09	%	$	367,701	8	%	$	459,627	10	%
	Glacier Bank	851,819		18.79	%	362,711		8	%	453,388		10	%
	Tier 1 capital (to risk-weighted assets)
	Consolidated	$	865,213	18.82	%	$	183,851	4	%	$	275,776	6	%
	Glacier Bank	794,228		17.52	%	181,355		4	%	272,033		6	%
	Tier 1 capital (to average assets)
	Consolidated	$	865,213	11.31	%	$	306,005	4	%	N/A		N/A
	Glacier Bank	794,228		10.55	%	301,013		4	%	$	376,267	5	%

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Components of Accumulated Other Comprehensive Income	'
	(Dollars in thousands)	31-Dec-13			31-Dec-12
	Unrealized gains on available-for-sale securities	$	13,888		95,328
	Tax effect	(5,403		)	(37,083	)
	Net of tax amount	8,485			58,245
	Unrealized gains (losses) on derivatives used for cash flow hedges	1,896			(16,832	)
	Tax effect	(736		)	6,549
	Net of tax amount	1,160			(10,283	)
	Total accumulated other comprehensive income	$	9,645		47,962

Federal_and_State_Income_Taxes1

Federal and State Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Summary of consolidated income tax expense (benefit)	'
		Years ended
	(Dollars in thousands)	December 31,				December 31,			December 31,
		2013				2012			2011
	Current
	Federal	$	18,377			12,718			8,836
	State	7,007				5,522			4,191
	Total current income tax expense	25,384				18,240			13,027
	Deferred
	Federal	3,918				708			(11,256	)
	State	715				129			(2,052	)
	Total deferred income tax expense (benefit)	4,633				837			(13,308	)
	Total income tax expense (benefit)	$	30,017			19,077			(281	)
Summary of effective tax rate	'
		Years ended
		December 31,			December 31,			December 31,
		2013			2012			2011
	Federal statutory rate	35	%		35	%		35	%
	State taxes, net of federal income tax benefit	4	%		3.9	%		8.1	%
	Tax-exempt interest income	(12.2	)%		(14.0	)%		(65.5	)%
	Tax credits	(3.2	)%		(4.2	)%		(22.1	)%
	Goodwill impairment charge	—	%		—	%		42.3	%
	Other, net	0.3	%		(0.5	)%		0.6	%
	Effective tax rate	23.9	%		20.2	%		(1.6	)%
Summary of net deferred tax asset	'
	(Dollars in thousands)	December 31,				December 31,
		2013				2012
	Deferred tax assets
	Allowance for loan and lease losses	$	50,652			50,963
	Other real estate owned	8,041				7,685
	Deferred compensation	4,837				3,129
	Employee benefits	3,132				2,715
	Federal income tax credits	2,778				3,543
	Interest rate swap agreements	—				6,549
	Other	7,813				7,835
	Total gross deferred tax assets	77,253				82,419
	Deferred tax liabilities
	FHLB stock dividends	(10,359		)		(10,143	)
	Deferred loan costs	(6,058		)		(5,316	)
	Available-for-sale securities	(5,402		)		(37,083	)
	Depreciation of premises and equipment	(3,939		)		(5,437	)
	Intangibles	(3,099		)		(1,117	)
	Interest rate swap agreements	(736		)		—
	Other	(4,111		)		(2,929	)
	Total gross deferred tax liabilities	(33,704		)		(62,025	)
	Net deferred tax asset	$	43,549			20,394
Income tax returns jurisdictions and years subject to examination	'
		Years ended December 31,
	Federal	2009, 2010, 2011 and 2012
	Montana	2010, 2011 and 2012
	Idaho	2009, 2010, 2011 and 2012
	Colorado	2009, 2010, 2011 and 2012
	Utah	2010, 2011 and 2012

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Basic and diluted earnings per share	'
		Years ended
	(Dollars in thousands, except per share data)	December 31,		December 31,	December 31,
		2013		2012	2011
	Net income available to common stockholders, basic and diluted	$	95,644	75,516	17,471
	Average outstanding shares - basic	73,191,713		71,928,570	71,915,073
	Add: dilutive stock options and awards	68,565		86	—
	Average outstanding shares - diluted	73,260,278		71,928,656	71,915,073
	Basic earnings per share	$	1.31	1.05	0.24
	Diluted earnings per share	$	1.31	1.05	0.24

Stockbased_Compensation_Plans_

Stock-based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Changes in shares granted for stock options	'
		Options		Weighted-
				Average
				Exercise Price
	Outstanding at December 31, 2012	791,440		$	16.95
	Exercised	(281,560	)	15.37
	Forfeited or expired	(451,070	)	18.14
	Outstanding at December 31, 2013	58,810		15.47
	Exercisable at December 31, 2013	58,810		15.47
Activity for restricted stock awards	'
		Restricted Stock		Weighted-
				Average
				Grant Date Fair Value
	Non-vested at December 31, 2012	—		$	—
	Granted	131,262		16.76
	Vested	(11,753	)	16.76
	Forfeited	(2,067	)	16.76
	Non-vested at December 31, 2013	117,442		16.76

Parent_Holding_Company_Informa1

Parent Holding Company Information (Condensed) (Tables)	12 Months Ended
	Dec. 31, 2013
Condensed Financial Information of Parent Company Only Disclosure [Abstract]	'
Statements of Financial Condition	'
	(Dollars in thousands)	December 31,			December 31,
		2013			2012
	Assets
	Cash on hand and in banks	$	1,582		2,540
	Interest bearing cash deposits	49,097			9,887
	Cash and cash equivalents	50,679			12,427
	Investment securities, available-for-sale	87			29,457
	Other assets	9,050			23,221
	Investment in subsidiaries	1,040,104			972,218
	Total assets	$	1,099,920		1,037,323
	Liabilities and Stockholders’ Equity
	Subordinated debentures	$	125,562		125,418
	Other liabilities	11,108			10,956
	Total liabilities	136,670			136,374
	Common stock	744			719
	Paid-in capital	690,918			641,737
	Retained earnings	261,943			210,531
	Accumulated other comprehensive income	9,645			47,962
	Total stockholders’ equity	963,250			900,949
	Total liabilities and stockholders’ equity	$	1,099,920		1,037,323
Statements of Operations	'
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Income
	Dividends from subsidiaries	$	65,445		78,209		43,450
	Loss on sale of investments	(3,248		)	—		—
	Other income	966			566		864
	Intercompany charges for services	7,387			16,041		14,438
	Total income	70,550			94,816		58,752
	Expenses
	Compensation and employee benefits	9,175			12,392		9,185
	Other operating expenses	6,536			10,267		11,827
	Total expenses	15,711			22,659		21,012
	Income before income tax benefit and equity in undistributed net income (loss) of subsidiaries	54,839			72,157		37,740
	Income tax benefit	3,676			2,319		2,176
	Income before equity in undistributed net income (loss) of subsidiaries	58,515			74,476		39,916
	Equity in undistributed net income (loss) of subsidiaries	37,129			1,040		(22,825	)
	Net Income	$	95,644		75,516		17,091
Statements of Comprehensive Income	'
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Net Income	$	95,644		75,516		17,091
	Other Comprehensive (Loss) Income, Net of Tax
	Unrealized (losses) gains on available-for-sale securities	(81,739		)	31,617		63,190
	Reclassification adjustment for losses (gains) included in net income	299			—		(346	)
	Net unrealized (losses) gains on securities	(81,440		)	31,617		62,844
	Tax effect	31,680			(12,300	)	(24,444	)
	Net of tax amount	(49,760		)	19,317		38,400
	Unrealized gains (losses) on derivatives used for cash flow hedges	18,728			(7,926	)	(8,906	)
	Tax effect	(7,285		)	3,084		3,465
	Net of tax amount	11,443			(4,842	)	(5,441	)
	Total other comprehensive (loss) income, net of tax	(38,317		)	14,475		32,959
	Total Comprehensive Income	$	57,327		89,991		50,050
Statements of Cash Flows	'
		Years ended
	(Dollars in thousands)	December 31,			December 31,		December 31,
		2013			2012		2011
	Operating Activities
	Net income	$	95,644		75,516		17,091
	Adjustments to reconcile net income to net cash provided by operating activities:
	Subsidiary income (in excess of) less than dividends distributed	(37,129		)	(1,040	)	22,825
	Loss on sale of investments	3,248			—		—
	Excess tax deficiencies from stock-based compensation	223			8		—
	Net change in other assets and other liabilities	2,575			3,684		1,215
	Net cash provided by operating activities	64,561			78,168		41,131
	Investing Activities
	Proceeds from sales, maturities and prepayments of securities available-for-sale	26,561			787		1,376
	Changes in investment securities and other stock - intercompany	(946		)	(19,183	)	—
	Equity contribution to subsidiaries	(11,336		)	(28,500	)	(1,110	)
	Net addition of premises and equipment	(603		)	(2,927	)	(1,920	)
	Net cash provided by (used in) investing activities	13,676			(49,823	)	(1,654	)
	Financing Activities
	Net increase in other borrowed funds	144			143		143
	Cash dividends paid	(44,232		)	(47,472	)	(37,395	)
	Excess tax deficiencies from stock-based compensation	(223		)	(8	)	—
	Proceeds from stock options exercised	4,326			81		—
	Net cash used in financing activities	(39,985		)	(47,256	)	(37,252	)
	Net increase (decrease) in cash and cash equivalents	38,252			(18,911	)	2,225
	Cash and cash equivalents at beginning of year	12,427			31,338		29,113
	Cash and cash equivalents at end of year	$	50,679		12,427		31,338

Unaudited_Quarterly_Financial_1

Unaudited Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Summarized unaudited quarterly financial data	'
		Quarters ended 2013
	(Dollars in thousands, except per share data)	March 31		June 30	September 30	December 31
	Interest income	$	57,955	62,151	69,531	73,939
	Interest expense	7,458		7,185	7,186	6,929
	Net interest income	50,497		54,966	62,345	67,010
	Provision for loan losses	2,100		1,078	1,907	1,802
	Net interest income after provision for loan losses	48,397		53,888	60,438	65,208
	Non-interest income	22,950		23,222	23,873	23,002
	Non-interest expense	43,434		48,481	50,368	53,034
	Income before income taxes	27,913		28,629	33,943	35,176
	Federal and state income tax expense	7,145		5,927	8,315	8,630
	Net income	20,768		22,702	25,628	26,546
	Basic earnings per share	0.29		0.31	0.35	0.36
	Diluted earnings per share	0.29		0.31	0.35	0.36
		Quarters ended 2012
	(Dollars in thousands, except per share data)	March 31		June 30	September 30	December 31
	Interest income	$	67,884	64,192	62,015	59,666
	Interest expense	9,598		9,044	8,907	8,165
	Net interest income	58,286		55,148	53,108	51,501
	Provision for loan losses	8,625		7,925	2,700	2,275
	Net interest income after provision for loan losses	49,661		47,223	50,408	49,226
	Non-interest income	20,338		21,791	23,974	25,393
	Non-interest expense	49,045		46,190	50,178	48,008
	Income before income taxes	20,954		22,824	24,204	26,611
	Federal and state income tax expense	4,621		3,843	4,760	5,853
	Net income	16,333		18,981	19,444	20,758
	Basic earnings per share	0.23		0.26	0.27	0.29
	Diluted earnings per share	0.23		0.26	0.27	0.29

Fair_Value_of_Assets_and_Liabi1

Fair Value of Assets and Liabilities (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair value measurement of assets and liabilities measured at fair value on a recurring basis	'
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Fair Value December 31, 2013		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Investment securities, available-for-sale
	U.S. government sponsored enterprises	$	10,628	—		10,628		—
	State and local governments	1,385,078		—		1,385,078		—
	Corporate bonds	442,501		—		442,501		—
	Residential mortgage-backed securities	1,384,622		—		1,384,622		—
	Interest rate swaps	1,896		—		1,896		—
	Total assets measured at fair value on a recurring basis	$	3,224,725	—		3,224,725		—
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Fair Value December 31, 2012		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Investment securities, available-for-sale
	U.S. government and federal agency	$	202	—		202		—
	U.S. government sponsored enterprises	17,480		—		17,480		—
	State and local governments	1,214,518		—		1,214,518		—
	Corporate bonds	288,795		—		288,795		—
	Collateralized debt obligations	1,708		—		1,708		—
	Residential mortgage-backed securities	2,160,302		—		2,160,302		—
	Total assets measured at fair value on a recurring basis	$	3,683,005	—		3,683,005		—
	Interest rate swaps	$	16,832	—		16,832		—
	Total liabilities measured at fair value on a recurring basis	$	16,832	—		16,832		—
Fair value measurement of assets measured at fair value on a non-recurring basis	'
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Fair Value December 31, 2013		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Other real estate owned	$	10,888	—		—		10,888
	Collateral-dependent impaired loans, net of ALLL	18,670		—		—		18,670
	Total assets measured at fair value on a non-recurring basis	$	29,558	—		—		29,558
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Fair Value December 31, 2012		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Other real estate owned	$	13,983	—		—		13,983
	Collateral-dependent impaired loans, net of ALLL	22,966		—		—		22,966
	Total assets measured at fair value on a non-recurring basis	$	36,949	—		—		36,949
Quantitative information about assets measured at fair value on a non-recurring basis for which Level 3 inputs were used	'
		Fair Value		Quantitative Information about Level 3 Fair Value Measurements
	(Dollars in thousands)	December 31,		Valuation Technique	Unobservable Input		Range (Weighted- Average) 1
		2013
	Other real estate owned	$	9,278	Sales comparison approach	Selling costs		7.0% - 10.0% (7.7%)
					Adjustment to comparables		0.0% - 37.5% (1.4%)
		1,610		Combined approach	Selling costs		5.0% - 10.0% (7.5%)
					Discount rate		8.5% - 8.5% (8.5%)
					Adjustment to comparables		25.0% - 25.0% (25.0%)
		$	10,888
	Collateral-dependent impaired loans, net of ALLL	$	4,076	Income approach	Selling costs		8.0% - 8.0% (8.0%)
					Discount rate		8.3% - 8.3% (8.3%)
		11,784		Sales comparison approach	Selling costs		0.0% - 10.0% (7.9%)
					Adjustment to comparables		0.0% - 1.0% (0.0%)
		2,810		Combined approach	Selling costs		0.0% - 8.0% (7.8%)
					Discount rate		7.3% - 7.3% (7.3%)
					Adjustment to comparables		10.0% - 50.0% (18.9%)
		$	18,670
		Fair Value		Quantitative Information about Level 3 Fair Value Measurements
	(Dollars in thousands)	December 31,		Valuation Technique	Unobservable Input		Range (Weighted- Average) 1
		2012
	Other real estate owned	$	93	Cost approach	Selling costs		7.0% - 7.0% (7.0%)
		11,787		Sales comparison approach	Selling costs		7.0% - 14.0% (7.9%)
					Adjustment to comparables		0.0% - 37.0% (11.7%)
		2,103		Combined approach	Selling costs		5.0% - 8.0% (6.6%)
					Discount rate		25.0% - 25.0% (25.0%)
					Adjustment to comparables		0.0% - 30.0% (7.7%)
		$	13,983
	Collateral-dependent impaired loans, net of ALLL	$	84	Cost approach	Selling costs		8.0% - 8.0% (8.0%)
		5,509		Income approach	Selling costs		8.0% - 10.0% (8.2%)
					Discount rate		0.0% - 8.3% (6.3%)
		12,878		Sales comparison approach	Selling costs		0.0% - 16.0% (8.6%)
					Adjustment to comparables		0.0% - 12.0% (1.6%)
		4,495		Combined approach	Selling costs		8.0% - 10.0% (8.4%)
					Discount rate		8.0% - 8.0% (8.0%)
					Adjustment to comparables		0.0% - 36.0% (17.6%)
		$	22,966
	__________
	1 The range for selling costs and adjustments to comparables indicate reductions to the fair value.
Carrying amounts and estimated fair values of financial instruments	'
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Carrying Amount December 31, 2013		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Financial assets
	Cash and cash equivalents	$	155,657	155,657		—		—
	Investment securities, available-for-sale	3,222,829		—		3,222,829		—
	Loans held for sale	46,738		46,738		—		—
	Loans receivable, net of ALLL	3,932,487		—		3,807,993		187,731
	Accrued interest receivable	41,898		41,898		—		—
	Non-marketable equity securities	52,192		—		52,192		—
	Interest rate swaps	1,896		—		1,896		—
	Total financial assets	$	7,453,697	244,293		7,084,910		187,731
	Financial liabilities
	Deposits	$	5,579,967	4,258,213		1,341,382		—
	FHLB advances	840,182		—		857,551		—
	Repurchase agreements and other borrowed funds	321,781		—		321,781		—
	Subordinated debentures	125,562		—		71,501		—
	Accrued interest payable	3,505		3,505		—		—
	Total financial liabilities	$	6,870,997	4,261,718		2,592,215		—
				Fair Value Measurements
				At the End of the Reporting Period Using
	(Dollars in thousands)	Carrying Amount December 31, 2012		Quoted Prices		Significant		Significant
				in Active  Markets		Other		Unobservable
				for Identical		Observable		Inputs
				Assets		Inputs		(Level 3)
				(Level 1)		(Level 2)
	Financial assets
	Cash and cash equivalents	$	187,040	187,040		—		—
	Investment securities, available-for-sale	3,683,005		—		3,683,005		—
	Loans held for sale	145,501		145,501		—		—
	Loans receivable, net of ALLL	3,266,571		—		3,184,987		186,201
	Accrued interest receivable	37,770		37,770		—		—
	Non-marketable equity securities	48,812		—		48,812		—
	Total financial assets	$	7,368,699	370,311		6,916,804		186,201
	Financial liabilities
	Deposits	$	5,364,461	3,585,126		1,789,134		—
	FHLB advances	997,013		—		1,027,101		—
	Repurchase agreements and other borrowed funds	299,540		—		299,540		—
	Subordinated debentures	125,418		—		70,895		—
	Accrued interest payable	4,675		4,675		—		—
	Interest rate swaps	16,832		—		16,832		—
	Total financial liabilities	$	6,807,939	3,589,801		3,203,502		—

Contingencies_and_Commitments_

Contingencies and Commitments (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Outstanding commitments	'
	(Dollars in thousands)	December 31,		December 31,
		2013		2012
	Commitments to extend credit	$	866,885	802,595
	Letters of credit	14,665		12,600
	Total outstanding commitments	$	881,550	815,195

Mergers_and_Acquisitions_Table

Mergers and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2013
Business Combinations [Abstract]	'
Consideration transferred, identifiable net assets and resulting goodwill	'
		Wheatland		NCBI
	(Dollars in thousands)	May 31,		July 31,	Total
		2013		2013
	Fair value of consideration transferred
	Fair value of Company shares issued, net of equity issuance costs	$	28,290	16,743	45,033
	Cash consideration for outstanding shares	11,025		13,833	24,858
	Total fair value of consideration transferred	39,315		30,576	69,891
	Recognized amounts of identifiable assets acquired and liabilities assumed
	Identifiable assets acquired
	Cash and cash equivalents	23,148		27,865	51,013
	Investment securities, available-for-sale	75,643		48,058	123,701
	Loans receivable	171,199		215,986	387,185
	Core deposit intangible	2,079		3,660	5,739
	Accrued income and other assets	15,063		24,262	39,325
	Total identifiable assets acquired	287,132		319,831	606,963
	Liabilities assumed
	Deposits	255,197		294,980	550,177
	FHLB advances and other borrowed funds	5,467		—	5,467
	Accrued expenses and other liabilities	562		4,472	5,034
	Total liabilities assumed	261,226		299,452	560,678
	Total identifiable net assets	25,906		20,379	46,285
	Goodwill recognized	$	13,409	10,197	23,606
Unaudited Pro Forma Summary of the Company as if the Acquisitions had Occurred at the Beginning of the Period	'
		Year ended
	(Dollars in thousands)	December 31,		December 31,
		2013		2012
	Net interest income and non-interest income	$	339,236	334,317
	Net income	96,392		80,403

VIE_Carrying_Amounts_Included_

VIE Carrying Amounts Included in Financial Statements (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
CDE (NMTC)	'	'
Carrying amounts of the VIEs' assets and liabilities	'	'
Loans receivable	$36,039	$35,480
Premises and equipment, net	0	0
Accrued interest receivable	117	117
Other assets	843	1,114
Total assets	36,999	36,711
Other borrowed funds	4,555	4,555
Accrued interest payable	4	4
Other liabilities	151	182
Total liabilities	4,710	4,741
LIHTC	'	'
Carrying amounts of the VIEs' assets and liabilities	'	'
Loans receivable	0	0
Premises and equipment, net	13,536	16,066
Accrued interest receivable	0	0
Other assets	153	143
Total assets	13,689	16,209
Other borrowed funds	1,723	3,639
Accrued interest payable	5	6
Other liabilities	189	136
Total liabilities	$1,917	$3,781

Nature_of_Operations_and_Summa3

Nature of Operations and Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Dec. 31, 2013
Nature of Operations and Summary of Significant Accounting Policies	'
Number of Bank Divisions	13
Number of Operating Segments	1
Maximum Period of Original Maturity to be Included in Cash and Cash Equivalents	'3 months
Minimum period past due to consider loan as delinquent	'30 days
Minimum period past due to consider loan as non accrual	'90 days
Minimum number of days delinquent to charge off consumer loans	'120 days
Maximum period up to which purchase price of business is allocated to assets acquired and liabilities assumed	'1 year
Number of Reporting Units Subsequent to Aggregation for Goodwill Assessment	1
Percentage of likelihood for term more likely than not	50.00%
Minimum Range	'
Nature of Operations and Summary of Significant Accounting Policies	'
Number of years for home equity loan origination term	'10 years
Minimum Range | Office Buildings	'
Nature of Operations and Summary of Significant Accounting Policies	'
Useful life of premises and equipment	'15 years
Minimum Range | Furniture, fixtures and equipment	'
Nature of Operations and Summary of Significant Accounting Policies	'
Useful life of premises and equipment	'3 years
Maximum Range	'
Nature of Operations and Summary of Significant Accounting Policies	'
Number of years for home equity loan origination term	'15 years
Maximum Range | Office Buildings	'
Nature of Operations and Summary of Significant Accounting Policies	'
Useful life of premises and equipment	'40 years
Maximum Range | Furniture, fixtures and equipment	'
Nature of Operations and Summary of Significant Accounting Policies	'
Useful life of premises and equipment	'10 years

Cash_on_Hand_and_in_Banks_Deta

Cash on Hand and in Banks (Details Textual) (USD $)	Dec. 31, 2013
Cash and Cash Equivalents [Abstract]	'
Federal Reserve balance or cash on hand required	$20,011,000

Amortized_Cost_and_Fair_Value_

Amortized Cost and Fair Value of AFS Investment Securities (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Comparison of amortized cost and estimated fair value of investment securities, available-for-sale	'	'
Total Investment Securities, Weighted Yield	3.10%	2.71%
Total Investment Securities, Amortized Cost	$3,208,941,000	$3,587,677,000
Total Investment Securities, Gross Unrealized Gains	49,801,000	101,778,000
Total Investment Securities, Gross Unrealized Losses	-35,913,000	-6,450,000
Total Investment Securities, Fair Value	3,222,829,000	3,683,005,000
U.S. government and federal agency	'	'
Comparison of amortized cost and estimated fair value of investment securities, available-for-sale	'	'
Maturing within One Year, Weighted Yield	'	1.62%
Maturing within One Year, Amortized Cost	'	201,000
Maturing within One Year, Gross Unrealized Gains	'	1,000
Maturing within One Year, Gross Unrealized Losses	'	0
Maturing within One Year, Fair Value	'	202,000
U.S. government sponsored enterprises	'	'
Comparison of amortized cost and estimated fair value of investment securities, available-for-sale	'	'
Maturing after One Through Five Year, Weighted Yield	2.32%	2.30%
Maturing after Five Through Ten Years, Weighted Yield	2.00%	2.03%
Total Investment Securities, Weighted Yield	2.32%	2.29%
Maturing after One Through Five Years, Amortized Cost	10,405,000	17,064,000
Maturing after Five Through Ten Years, Amortized Cost	36,000	44,000
Total Investment Securities, Amortized Cost	10,441,000	17,108,000
Maturing after One Through Five Years Gross Unrealized Gains	187,000	371,000
Maturing after Five Through Ten Years Gross Unrealized Gains	0	1,000
Total Investment Securities, Gross Unrealized Gains	187,000	372,000
Maturing after One Through Five Years, Gross Unrealized Losses	0	0
Maturing after Five Through Ten Years, Gross Unrealized Losses	0	0
Total Investment Securities, Gross Unrealized Losses	0	0
Maturing after One Through Five Years, Fair Value	10,592,000	17,435,000
Maturing after Five Through Ten Years, Fair Value	36,000	45,000
Total Investment Securities, Fair Value	10,628,000	17,480,000
State and local governments	'	'
Comparison of amortized cost and estimated fair value of investment securities, available-for-sale	'	'
Maturing within One Year, Weighted Yield	2.22%	2.01%
Maturing after One Through Five Year, Weighted Yield	2.06%	2.11%
Maturing after Five Through Ten Years, Weighted Yield	3.21%	2.95%
Maturing after Ten Years, Weighted Yield	4.41%	4.70%
Total Investment Securities, Weighted Yield	4.06%	4.29%
Maturing within One Year, Amortized Cost	5,964,000	4,288,000
Maturing after One Through Five Years, Amortized Cost	174,826,000	149,497,000
Maturing after Five Through Ten Years, Amortized Cost	58,835,000	38,346,000
Maturing after Ten Years, Amortized Cost	1,137,722,000	935,897,000
Total Investment Securities, Amortized Cost	1,377,347,000	1,128,028,000
Maturing within One Year, Gross Unrealized Gains	57,000	28,000
Maturing after One Through Five Years Gross Unrealized Gains	3,486,000	4,142,000
Maturing after Five Through Ten Years Gross Unrealized Gains	831,000	1,102,000
Maturing after Ten Years, Gross Unrealized Gains	27,247,000	82,823,000
Total Investment Securities, Gross Unrealized Gains	31,621,000	88,095,000
Maturing within One Year, Gross Unrealized Losses	0	-2,000
Maturing after One Through Five Years, Gross Unrealized Losses	-448,000	-142,000
Maturing after Five Through Ten Years, Gross Unrealized Losses	-1,040,000	-99,000
Maturing after Ten Years, Gross Unrealized Losses	-22,402,000	-1,362,000
Total Investment Securities, Gross Unrealized Losses	-23,890,000	-1,605,000
Maturing within One Year, Fair Value	6,021,000	4,314,000
Maturing after One Through Five Years, Fair Value	177,864,000	153,497,000
Maturing after Five Through Ten Years, Fair Value	58,626,000	39,349,000
Maturing after Ten Years, Fair Value	1,142,567,000	1,017,358,000
Total Investment Securities, Fair Value	1,385,078,000	1,214,518,000
Corporate bonds	'	'
Comparison of amortized cost and estimated fair value of investment securities, available-for-sale	'	'
Maturing within One Year, Weighted Yield	2.17%	1.73%
Maturing after One Through Five Year, Weighted Yield	2.09%	2.22%
Maturing after Five Through Ten Years, Weighted Yield	2.23%	2.23%
Total Investment Securities, Weighted Yield	2.11%	2.19%
Maturing within One Year, Amortized Cost	91,687,000	18,412,000
Maturing after One Through Five Years, Amortized Cost	341,799,000	250,027,000
Maturing after Five Through Ten Years, Amortized Cost	6,851,000	16,144,000
Total Investment Securities, Amortized Cost	440,337,000	284,583,000
Maturing within One Year, Gross Unrealized Gains	719,000	51,000
Maturing after One Through Five Years Gross Unrealized Gains	3,203,000	4,018,000
Maturing after Five Through Ten Years Gross Unrealized Gains	0	381,000
Total Investment Securities, Gross Unrealized Gains	3,922,000	4,450,000
Maturing within One Year, Gross Unrealized Losses	0	0
Maturing after One Through Five Years, Gross Unrealized Losses	-1,676,000	-238,000
Maturing after Five Through Ten Years, Gross Unrealized Losses	-82,000	0
Total Investment Securities, Gross Unrealized Losses	-1,758,000	-238,000
Maturing within One Year, Fair Value	92,406,000	18,463,000
Maturing after One Through Five Years, Fair Value	343,326,000	253,807,000
Maturing after Five Through Ten Years, Fair Value	6,769,000	16,525,000
Total Investment Securities, Fair Value	442,501,000	288,795,000
Collateralized debt obligations	'	'
Comparison of amortized cost and estimated fair value of investment securities, available-for-sale	'	'
Maturing after Ten Years, Weighted Yield	'	8.03%
Maturing after Ten Years, Amortized Cost	'	1,708,000
Maturing after Ten Years, Gross Unrealized Gains	'	0
Maturing after Ten Years, Gross Unrealized Losses	'	0
Maturing after Ten Years, Fair Value	'	1,708,000
Residential mortgage-backed securities	'	'
Comparison of amortized cost and estimated fair value of investment securities, available-for-sale	'	'
Total Investment Securities, Weighted Yield	2.48%	1.95%
Total Investment Securities, Amortized Cost	1,380,816,000	2,156,049,000
Total Investment Securities, Gross Unrealized Gains	14,071,000	8,860,000
Total Investment Securities, Gross Unrealized Losses	-10,265,000	-4,607,000
Total Investment Securities, Fair Value	$1,384,622,000	$2,160,302,000

Gain_or_Loss_on_Sale_of_Invest

Gain or Loss on Sale of Investments (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Gain and loss on sale of investments	'	'	'
Gross proceeds	$181,971	$0	$18,916
Less amortized cost	-182,270	0	-18,570
Net (loss) gain on sale of investments	-299	0	346
Gross gain on sale of investments	3,723	0	1,048
Gross loss on sale of investments	($4,022)	$0	($702)

Investments_with_an_Unrealized

Investments with an Unrealized Loss Position (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value	'	'
Fair Value, Less than 12 Months	$995,941	$1,099,987
Fair Value, 12 Months or More	77,856	67,438
Fair Value, Total	1,073,797	1,167,425
Unrealized Loss	'	'
Unrealized Loss, Less than 12 Months	-29,736	-5,810
Unrealized Loss, 12 Months or Longer	-6,177	-640
Unrealized Loss, Total	-35,913	-6,450
U.S. government sponsored enterprises	'	'
Fair Value	'	'
Fair Value, Less than 12 Months	3	'
Fair Value, 12 Months or More	0	'
Fair Value, Total	3	'
Unrealized Loss	'	'
Unrealized Loss, Less than 12 Months	0	'
Unrealized Loss, 12 Months or Longer	0	'
Unrealized Loss, Total	0	'
State and local governments	'	'
Fair Value	'	'
Fair Value, Less than 12 Months	408,812	102,896
Fair Value, 12 Months or More	74,161	4,533
Fair Value, Total	482,973	107,429
Unrealized Loss	'	'
Unrealized Loss, Less than 12 Months	-17,838	-1,531
Unrealized Loss, 12 Months or Longer	-6,052	-74
Unrealized Loss, Total	-23,890	-1,605
Corporate bonds	'	'
Fair Value	'	'
Fair Value, Less than 12 Months	129,515	41,856
Fair Value, 12 Months or More	1,702	0
Fair Value, Total	131,217	41,856
Unrealized Loss	'	'
Unrealized Loss, Less than 12 Months	-1,672	-238
Unrealized Loss, 12 Months or Longer	-86	0
Unrealized Loss, Total	-1,758	-238
Residential mortgage-backed securities	'	'
Fair Value	'	'
Fair Value, Less than 12 Months	457,611	955,235
Fair Value, 12 Months or More	1,993	62,905
Fair Value, Total	459,604	1,018,140
Unrealized Loss	'	'
Unrealized Loss, Less than 12 Months	-10,226	-4,041
Unrealized Loss, 12 Months or Longer	-39	-566
Unrealized Loss, Total	($10,265)	($4,607)

Investment_Securities_Availabl2

Investment Securities, Available-for-Sale (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Investment Securities, Available-for-Sale	'	'
Available-for-sale Securities	$3,222,829,000	$3,683,005,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments	49,801,000	101,778,000
Investment securities pledged as collateral	1,635,316,000	1,525,400,000
Other-than-temporary impairment on investment securities	0	0
Reclassification of AFS to HTM	'	'
Investment Securities, Available-for-Sale	'	'
Percent Available-For-Sale Prior to Reclassification	100.00%	'
Percent Available-For-Sale Subsequent to Reclassification	85.00%	'
Percent Held-To-Maturity Subsequent to Reclassification	15.00%	'
State and local governments	'	'
Investment Securities, Available-for-Sale	'	'
Available-for-sale Securities	1,385,078,000	1,214,518,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments	31,621,000	88,095,000
State and local governments | Reclassification of AFS to HTM	'	'
Investment Securities, Available-for-Sale	'	'
Available-for-sale Securities	484,583,000	'
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments	4,624,000	'
Residential mortgage-backed securities	'	'
Investment Securities, Available-for-Sale	'	'
Non-guaranteed private label whole loan mortgage-backed securities	2,602,000	46,733,000
Available-for-sale Securities	1,384,622,000	2,160,302,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments	$14,071,000	$8,860,000

ALLL_Activity_Details

ALLL Activity (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for loan and lease losses	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	$130,854	'	'	'	$137,516	$130,854	$137,516	$137,107
Provision for loan losses	1,802	1,907	1,078	2,100	2,275	2,700	7,925	8,625	6,887	21,525	64,500
Charge-offs	'	'	'	'	'	'	'	'	-13,643	-34,672	-69,366
Recoveries	'	'	'	'	'	'	'	'	6,253	6,485	5,275
Balance at end of period	130,351	'	'	'	130,854	'	'	'	130,351	130,854	137,516
Residential Real Estate	'	'	'	'	'	'	'	'	'	'	'
Allowance for loan and lease losses	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	15,482	'	'	'	17,227	15,482	17,227	20,957
Provision for loan losses	'	'	'	'	'	'	'	'	-921	2,879	1,455
Charge-offs	'	'	'	'	'	'	'	'	-793	-5,267	-5,671
Recoveries	'	'	'	'	'	'	'	'	299	643	486
Balance at end of period	14,067	'	'	'	15,482	'	'	'	14,067	15,482	17,227
Commercial Real Estate	'	'	'	'	'	'	'	'	'	'	'
Allowance for loan and lease losses	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	74,398	'	'	'	76,920	74,398	76,920	76,147
Provision for loan losses	'	'	'	'	'	'	'	'	-3,670	11,012	39,563
Charge-offs	'	'	'	'	'	'	'	'	-3,736	-16,339	-42,042
Recoveries	'	'	'	'	'	'	'	'	3,340	2,805	3,252
Balance at end of period	70,332	'	'	'	74,398	'	'	'	70,332	74,398	76,920
Other Commercial	'	'	'	'	'	'	'	'	'	'	'
Allowance for loan and lease losses	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	21,567	'	'	'	20,833	21,567	20,833	19,932
Provision for loan losses	'	'	'	'	'	'	'	'	10,271	4,690	10,709
Charge-offs	'	'	'	'	'	'	'	'	-4,671	-5,239	-10,386
Recoveries	'	'	'	'	'	'	'	'	1,463	1,283	578
Balance at end of period	28,630	'	'	'	21,567	'	'	'	28,630	21,567	20,833
Home Equity	'	'	'	'	'	'	'	'	'	'	'
Allowance for loan and lease losses	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	10,659	'	'	'	13,616	10,659	13,616	13,334
Provision for loan losses	'	'	'	'	'	'	'	'	868	324	4,450
Charge-offs	'	'	'	'	'	'	'	'	-2,594	-4,369	-4,644
Recoveries	'	'	'	'	'	'	'	'	366	1,088	476
Balance at end of period	9,299	'	'	'	10,659	'	'	'	9,299	10,659	13,616
Other Consumer	'	'	'	'	'	'	'	'	'	'	'
Allowance for loan and lease losses	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	8,748	'	'	'	8,920	8,748	8,920	6,737
Provision for loan losses	'	'	'	'	'	'	'	'	339	2,620	8,323
Charge-offs	'	'	'	'	'	'	'	'	-1,849	-3,458	-6,623
Recoveries	'	'	'	'	'	'	'	'	785	666	483
Balance at end of period	$8,023	'	'	'	$8,748	'	'	'	$8,023	$8,748	$8,920

Loans_Receivable_Net_ALLL_and_

Loans Receivable, Net ALLL and Loans Receivable Summary (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Allowance for Loan and Lease Losses and Loans Receivable	'	'
Individually evaluated for impairment	$11,949	$15,534
Collectively evaluated for impairment	118,402	115,320
Total allowance for loan and lease losses	130,351	130,854
Individually evaluated for impairment	199,680	201,735
Collectively evaluated for impairment	3,863,158	3,195,690
Total loans receivable	4,062,838	3,397,425
Residential Real Estate	'	'
Allowance for Loan and Lease Losses and Loans Receivable	'	'
Individually evaluated for impairment	990	1,680
Collectively evaluated for impairment	13,077	13,802
Total allowance for loan and lease losses	14,067	15,482
Individually evaluated for impairment	24,070	25,862
Collectively evaluated for impairment	553,519	490,605
Total loans receivable	577,589	516,467
Commercial Real Estate	'	'
Allowance for Loan and Lease Losses and Loans Receivable	'	'
Individually evaluated for impairment	3,763	7,716
Collectively evaluated for impairment	66,569	66,682
Total allowance for loan and lease losses	70,332	74,398
Individually evaluated for impairment	119,526	125,282
Collectively evaluated for impairment	1,929,721	1,530,226
Total loans receivable	2,049,247	1,655,508
Other Commercial	'	'
Allowance for Loan and Lease Losses and Loans Receivable	'	'
Individually evaluated for impairment	6,155	3,859
Collectively evaluated for impairment	22,475	17,708
Total allowance for loan and lease losses	28,630	21,567
Individually evaluated for impairment	41,504	33,593
Collectively evaluated for impairment	810,532	589,804
Total loans receivable	852,036	623,397
Home Equity	'	'
Allowance for Loan and Lease Losses and Loans Receivable	'	'
Individually evaluated for impairment	265	870
Collectively evaluated for impairment	9,034	9,789
Total allowance for loan and lease losses	9,299	10,659
Individually evaluated for impairment	9,039	11,074
Collectively evaluated for impairment	357,426	392,851
Total loans receivable	366,465	403,925
Other Consumer	'	'
Allowance for Loan and Lease Losses and Loans Receivable	'	'
Individually evaluated for impairment	776	1,409
Collectively evaluated for impairment	7,247	7,339
Total allowance for loan and lease losses	8,023	8,748
Individually evaluated for impairment	5,541	5,924
Collectively evaluated for impairment	211,960	192,204
Total loans receivable	$217,501	$198,128

Impaired_Loans_Details

Impaired Loans (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Summary of the impaired loans by portfolio class of loans	'	'
Loans with a Specific Valuation Allowance, Recorded Balance	$61,503	$62,759
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	63,406	70,261
Loans with a Specific Valuation Allowance, Specific Valuation Allowance	11,949	15,534
Loans with a Specific Valuation Allowance, Average Balance	59,823	76,656
Loans without a Specific Valuation Allowance, Recorded Balance	138,177	138,976
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	169,082	149,412
Loans without a Specific Valuation Allowance, Average Balance	139,129	162,505
Recorded balance	199,680	201,735
Unpaid principal balance	232,488	219,673
Specific valuation allowance	11,949	15,534
Average balance	198,952	239,161
Residential Real Estate	'	'
Summary of the impaired loans by portfolio class of loans	'	'
Loans with a Specific Valuation Allowance, Recorded Balance	7,233	7,334
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	7,394	7,459
Loans with a Specific Valuation Allowance, Specific Valuation Allowance	990	1,680
Loans with a Specific Valuation Allowance, Average Balance	7,237	12,797
Loans without a Specific Valuation Allowance, Recorded Balance	16,837	18,528
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	18,033	19,613
Loans without a Specific Valuation Allowance, Average Balance	18,103	16,034
Recorded balance	24,070	25,862
Unpaid principal balance	25,427	27,072
Specific valuation allowance	990	1,680
Average balance	25,340	28,831
Commercial Real Estate	'	'
Summary of the impaired loans by portfolio class of loans	'	'
Loans with a Specific Valuation Allowance, Recorded Balance	23,917	29,595
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	25,331	36,887
Loans with a Specific Valuation Allowance, Specific Valuation Allowance	3,763	7,716
Loans with a Specific Valuation Allowance, Average Balance	26,105	36,164
Loans without a Specific Valuation Allowance, Recorded Balance	95,609	95,687
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	119,017	102,798
Loans without a Specific Valuation Allowance, Average Balance	95,808	111,554
Recorded balance	119,526	125,282
Unpaid principal balance	144,348	139,685
Specific valuation allowance	3,763	7,716
Average balance	121,913	147,718
Other Commercial	'	'
Summary of the impaired loans by portfolio class of loans	'	'
Loans with a Specific Valuation Allowance, Recorded Balance	27,015	21,205
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	27,238	21,278
Loans with a Specific Valuation Allowance, Specific Valuation Allowance	6,155	3,859
Loans with a Specific Valuation Allowance, Average Balance	22,460	22,665
Loans without a Specific Valuation Allowance, Recorded Balance	14,489	12,388
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	19,156	14,318
Loans without a Specific Valuation Allowance, Average Balance	14,106	19,733
Recorded balance	41,504	33,593
Unpaid principal balance	46,394	35,596
Specific valuation allowance	6,155	3,859
Average balance	36,566	42,398
Home Equity	'	'
Summary of the impaired loans by portfolio class of loans	'	'
Loans with a Specific Valuation Allowance, Recorded Balance	886	1,354
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	949	1,362
Loans with a Specific Valuation Allowance, Specific Valuation Allowance	265	870
Loans with a Specific Valuation Allowance, Average Balance	767	1,390
Loans without a Specific Valuation Allowance, Recorded Balance	8,153	9,720
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	9,631	9,965
Loans without a Specific Valuation Allowance, Average Balance	8,844	11,993
Recorded balance	9,039	11,074
Unpaid principal balance	10,580	11,327
Specific valuation allowance	265	870
Average balance	9,611	13,383
Other Consumer	'	'
Summary of the impaired loans by portfolio class of loans	'	'
Loans with a Specific Valuation Allowance, Recorded Balance	2,452	3,271
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	2,494	3,275
Loans with a Specific Valuation Allowance, Specific Valuation Allowance	776	1,409
Loans with a Specific Valuation Allowance, Average Balance	3,254	3,640
Loans without a Specific Valuation Allowance, Recorded Balance	3,089	2,653
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	3,245	2,718
Loans without a Specific Valuation Allowance, Average Balance	2,268	3,191
Recorded balance	5,541	5,924
Unpaid principal balance	5,739	5,993
Specific valuation allowance	776	1,409
Average balance	$5,522	$6,831

Loans_Receivable_Aging_Analysi

Loans Receivable Aging Analysis (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Loan portfolio aging analysis	'	'
Accruing loans 30-59 days past due	$25,761	$17,454
Accruing loans 60-89 days past due	6,355	9,643
Accruing loans 90 days or more past due	604	1,479
Non-accrual loans	81,956	96,933
Total past due and non-accrual loans	114,676	125,509
Current loans receivable	3,948,162	3,271,916
Total loans receivable	4,062,838	3,397,425
Residential Real Estate	'	'
Loan portfolio aging analysis	'	'
Accruing loans 30-59 days past due	10,367	3,897
Accruing loans 60-89 days past due	1,055	1,870
Accruing loans 90 days or more past due	429	451
Non-accrual loans	10,702	14,237
Total past due and non-accrual loans	22,553	20,455
Current loans receivable	555,036	496,012
Total loans receivable	577,589	516,467
Commercial Real Estate	'	'
Loan portfolio aging analysis	'	'
Accruing loans 30-59 days past due	7,016	7,424
Accruing loans 60-89 days past due	2,709	3,745
Accruing loans 90 days or more past due	0	594
Non-accrual loans	51,438	55,687
Total past due and non-accrual loans	61,163	67,450
Current loans receivable	1,988,084	1,588,058
Total loans receivable	2,049,247	1,655,508
Other Commercial	'	'
Loan portfolio aging analysis	'	'
Accruing loans 30-59 days past due	3,673	2,020
Accruing loans 60-89 days past due	1,421	645
Accruing loans 90 days or more past due	160	197
Non-accrual loans	10,139	13,200
Total past due and non-accrual loans	15,393	16,062
Current loans receivable	836,643	607,335
Total loans receivable	852,036	623,397
Home Equity	'	'
Loan portfolio aging analysis	'	'
Accruing loans 30-59 days past due	2,432	2,872
Accruing loans 60-89 days past due	668	2,980
Accruing loans 90 days or more past due	5	188
Non-accrual loans	7,950	11,241
Total past due and non-accrual loans	11,055	17,281
Current loans receivable	355,410	386,644
Total loans receivable	366,465	403,925
Other Consumer	'	'
Loan portfolio aging analysis	'	'
Accruing loans 30-59 days past due	2,273	1,241
Accruing loans 60-89 days past due	502	403
Accruing loans 90 days or more past due	10	49
Non-accrual loans	1,727	2,568
Total past due and non-accrual loans	4,512	4,261
Current loans receivable	212,989	193,867
Total loans receivable	$217,501	$198,128

Troubled_Debt_Restructurings_D

Troubled Debt Restructurings (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Loan	Loan	Loan
Troubled Debt Restructurings	'	'	'
Troubled Debt Restructurings, Number of Loans	63	198	338
Troubled Debt Restructurings, Pre-Modification Recorded Balance	$29,046	$90,747	$158,295
Troubled Debt Restructurings, Post-Modification Recorded Balance	29,359	89,558	155,827
TDRs that Subsequently Defaulted, Number of Loans	5	14	66
TDRs that Subsequently Defaulted, Recorded Balance	849	8,304	41,236
Residential Real Estate	'	'	'
Troubled Debt Restructurings	'	'	'
Troubled Debt Restructurings, Number of Loans	9	11	20
Troubled Debt Restructurings, Pre-Modification Recorded Balance	1,907	2,280	13,500
Troubled Debt Restructurings, Post-Modification Recorded Balance	2,293	2,281	13,452
TDRs that Subsequently Defaulted, Number of Loans	1	0	4
TDRs that Subsequently Defaulted, Recorded Balance	265	0	2,291
Commercial Real Estate	'	'	'
Troubled Debt Restructurings	'	'	'
Troubled Debt Restructurings, Number of Loans	21	85	120
Troubled Debt Restructurings, Pre-Modification Recorded Balance	20,334	57,382	109,593
Troubled Debt Restructurings, Post-Modification Recorded Balance	20,334	56,120	107,778
TDRs that Subsequently Defaulted, Number of Loans	1	4	29
TDRs that Subsequently Defaulted, Recorded Balance	79	6,192	32,615
Other Commercial	'	'	'
Troubled Debt Restructurings	'	'	'
Troubled Debt Restructurings, Number of Loans	23	75	149
Troubled Debt Restructurings, Pre-Modification Recorded Balance	6,087	28,639	20,446
Troubled Debt Restructurings, Post-Modification Recorded Balance	6,087	28,711	20,434
TDRs that Subsequently Defaulted, Number of Loans	3	6	22
TDRs that Subsequently Defaulted, Recorded Balance	505	1,753	2,718
Home Equity	'	'	'
Troubled Debt Restructurings	'	'	'
Troubled Debt Restructurings, Number of Loans	2	10	22
Troubled Debt Restructurings, Pre-Modification Recorded Balance	147	1,358	9,198
Troubled Debt Restructurings, Post-Modification Recorded Balance	147	1,358	9,200
TDRs that Subsequently Defaulted, Number of Loans	0	3	7
TDRs that Subsequently Defaulted, Recorded Balance	0	301	3,202
Other Consumer	'	'	'
Troubled Debt Restructurings	'	'	'
Troubled Debt Restructurings, Number of Loans	8	17	27
Troubled Debt Restructurings, Pre-Modification Recorded Balance	571	1,088	5,558
Troubled Debt Restructurings, Post-Modification Recorded Balance	498	1,088	4,963
TDRs that Subsequently Defaulted, Number of Loans	0	1	4
TDRs that Subsequently Defaulted, Recorded Balance	$0	$58	$410

Loans_Receivable_Net_Details_T

Loans Receivable, Net (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Troubled Debt Restructurings	'	'	'
Percentage of Troubled Debt Restructurings Resulting from Extensions of Maturity Date	71.00%	49.00%	58.00%
TDR With Pre Modification Loan Balance for Which Oreo Was Received	$18,345,000	$39,769,000	$96,528,000
Additional outstanding commitments on TDRs	2,024,000	4,534,000	'
Charge-offs on TDRs	1,945,000	6,271,000	8,792,000
Loans Receivable	'	'	'
Percentage of consolidated stockholders equity exceeding which no borrower had outstanding loans or commitments	10.00%	'	'
Net deferred fees, premiums, and discounts included in the loan receivable	10,662,000	1,379,000	'
Variable rate loans	2,566,042,000	'	'
Fixed rate loans	1,496,796,000	'	'
Weighted average interest rate on loans	5.04%	5.33%	'
Loan sold and serviced for others	148,376,000	116,439,000	160,465,000
Loans pledged as collateral	2,579,874,000	'	'
Aggregate amount of loans outstanding to related parties	35,224,000	33,869,000	'
New loans to related parties	4,311,000	'	'
Repayments of loans by related parties	2,956,000	'	'
Interest income that would have been recorded on non-accrual loans	$4,122,000	$5,161,000	$7,441,000
Commercial Real Estate	'	'	'
Troubled Debt Restructurings	'	'	'
Percentage of Troubled Debt Restructurings Resulting from Extensions of Maturity Date	87.00%	36.00%	56.00%
Percentage of TDRs Resulting of Combination of Interest Rate Reduction Extension of Maturity Date or Reduction in Face Amount	9.00%	30.00%	31.00%

Premises_and_Equipment_Net_of_

Premises and Equipment, Net of Accumulated Depreciation (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Premises and Equipment, Net of Accumulated Depreciation	'	'
Accumulated depreciation	($92,944)	($90,238)
Premises and Equipment, Net	167,671	158,989
Land	'	'
Premises and Equipment, Net of Accumulated Depreciation	'	'
Premises and equipment, gross	27,260	25,027
Office buildings and construction in progress	'	'
Premises and Equipment, Net of Accumulated Depreciation	'	'
Premises and equipment, gross	159,391	153,340
Furniture, fixtures and equipment	'	'
Premises and Equipment, Net of Accumulated Depreciation	'	'
Premises and equipment, gross	66,375	63,467
Leasehold improvements	'	'
Premises and Equipment, Net of Accumulated Depreciation	'	'
Premises and equipment, gross	$7,589	$7,393

Premises_and_Equipment_Future_

Premises and Equipment Future Minimum Rental Commitments under Operating and Capital Leases (Details) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Capital Leases	'
For the Year Ended December 31, 2014	$828
For the Year Ended December 31, 2015	195
For the Year Ended December 31, 2016	197
For the Year Ended December 31, 2017	200
For the Year Ended December 31, 2018	203
Thereafter	546
Total Minimum Lease Payments	2,169
Less: Amount representing interest	479
Present value of minimum lease payments	1,690
Less: Current portion of obligations under capital leases	708
Long-term portion of obligations under capital leases	982
Operating Leases	'
For the Year Ended December 31, 2014	2,297
For the Year Ended December 31, 2015	2,120
For the Year Ended December 31, 2016	1,879
For the Year Ended December 31, 2017	1,577
For the Year Ended December 31, 2018	1,375
Thereafter	2,900
Total Minimum Lease Payments	12,148
Total	'
For the Year Ended December 31, 2014	3,125
For the Year Ended December 31, 2015	2,315
For the Year Ended December 31, 2016	2,076
For the Year Ended December 31, 2017	1,777
For the Year Ended December 31, 2018	1,578
Thereafter	3,446
Total Minimum Lease Payments	$14,317

Premises_and_Equipment_Details

Premises and Equipment (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Premises and Equipment	'	'	'
Depreciation expense	$10,485,000	$10,615,000	$10,443,000
Total rent expense	2,912,000	2,868,000	3,239,000
Related party rent expense	$142,000	$410,000	$937,000

Net_Carrying_Value_of_Core_Dep

Net Carrying Value of Core Deposit Intangibles (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net Core Deposit Intangibles and Aggregate Amortization Expense	'	'	'
Net carrying value	$9,512,000	$6,174,000	'
Aggregate amortization expense	2,401,000	2,110,000	2,473,000
Core Deposits Intangibles	'	'	'
Net Core Deposit Intangibles and Aggregate Amortization Expense	'	'	'
Gross carrying value	27,857,000	22,404,000	28,248,000
Accumulated amortization	-18,345,000	-16,230,000	-19,964,000
Net carrying value	9,512,000	6,174,000	8,284,000
Aggregate amortization expense	2,401,000	2,110,000	2,473,000
Estimated Amortization Expense	'	'	'
For the year ending December 31, 2014	2,650,000	'	'
For the year ending December 31, 2015	2,198,000	'	'
For the year ending December 31, 2016	1,700,000	'	'
For the year ending December 31, 2017	828,000	'	'
For the year ending December 31, 2018	430,000	'	'
Core Deposit Intangibles Acquired During the Year	'	'	'
Core Deposit Intangibles Acquired	$5,739,000	'	'
Core Deposits Intangibles | Weighted Average	'	'	'
Net Core Deposit Intangibles and Aggregate Amortization Expense	'	'	'
Weighted-average amortization period (Period in years)	'9 years 6 months	'	'

Changes_in_the_Carrying_Value_

Changes in the Carrying Value of Goodwill (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill Roll Forward	'	'	'
Net carrying value at beginning of period	$106,100	$106,100	$146,259
Acquisitions	23,606	0	0
Impairment charge	0	0	-40,159
Net carrying value at end of period	$129,706	$106,100	$106,100

Other_Intangible_Assets_and_Go2

Other Intangible Assets and Goodwill Net Carrying Value of Goodwill (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Thousands, unless otherwise specified
Gross carrying value of goodwill and the accumulated impairment charge	'	'	'	'
Gross carrying value	$169,865	$146,259	'	'
Accumulated impairment charge	-40,159	-40,159	'	'
Net carrying value	$129,706	$106,100	$106,100	$146,259

Summary_of_Deposits_Details

Summary of Deposits (Details) (USD $)	Dec. 31, 2013		Dec. 31, 2012
In Thousands, unless otherwise specified
Non-interest bearing deposits	'		'
Non-interest bearing deposits	$1,374,419		$1,191,933
Non-interest Bearing Deposits, Percentage	24.60%		22.20%
Interest bearing deposits	'		'
NOW accounts	1,113,878		988,984
NOW accounts, Percentage	20.00%		18.40%
Savings accounts	600,998		478,809
Savings accounts, Percentage	10.80%		8.90%
Money market deposit accounts	1,168,918		931,370
Money market deposit accounts, Percentage	20.90%		17.40%
Certificate accounts	1,116,622		1,015,491
Certificate accounts, Percentage	20.00%		19.00%
Wholesale deposits	205,132	[1]	757,874	[1]
Wholesale deposits, Percentage	3.70%	[1]	14.10%	[1]
Total interest bearing deposits	4,205,548		4,172,528
Total interest bearing deposits, Percentage	75.40%		77.80%
Total deposits	5,579,967		5,364,461
Total deposits, Percentage	100.00%		100.00%
Deposits with a balance of $100,000 and greater	'		'
Demand deposits	2,685,577		2,361,528
Certificate accounts	661,924		1,044,488
Total balances of $100,000 and greater	$3,347,501		$3,406,016
[1]	Wholesale deposits include brokered deposits classified as NOW, money market deposit and certificate accounts.

Scheduled_Maturities_of_Time_D

Scheduled Maturities of Time Deposits (Details 1) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Maturities of Time Deposits	'
For the year ending December 31, 2014	$864,633
For the year ending December 31, 2015	164,104
For the year ending December 31, 2016	79,425
For the year ending December 31, 2017	33,975
For the year ending December 31, 2018	19,244
Thereafter	7,220
Total	$1,168,601

Deposits_Details_Textual

Deposits (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Deposits	'	'	'
Wholesale deposits included in time deposits	$51,979,000	'	'
Overdraft demand deposits reclassified as loans	3,422,000	3,482,000	'
Deposits with related parties	12,770,000	20,404,000	'
Debit card expense	$6,131,000	$4,497,000	$4,400,000

Securities_Sold_Under_Agreemen2

Securities Sold Under Agreements to Repurchase (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Repurchase Agreements	'	'
Repurchase Amount	$313,394	$289,508
Weighted Average Fixed Rate	0.28%	0.32%
Amortized Cost of Underlying Assets	315,358	291,825
Fair Value of Underlying Assets	324,157	298,264
Overnight	'	'
Repurchase Agreements	'	'
Repurchase Amount	303,709	285,349
Weighted Average Fixed Rate	0.28%	0.32%
Amortized Cost of Underlying Assets	304,263	287,597
Fair Value of Underlying Assets	312,856	293,958
Maturing within 30 days	'	'
Repurchase Agreements	'	'
Repurchase Amount	9,685	4,159
Weighted Average Fixed Rate	0.32%	0.50%
Amortized Cost of Underlying Assets	11,095	4,228
Fair Value of Underlying Assets	$11,301	$4,306

Summary_of_FHLB_Advances_Detai

Summary of FHLB Advances (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
FHLB Advances	'	'
Maturing within one year, Amount	$559,084	$720,000
Maturing within one year, Weighted rate	0.24%	0.28%
Maturing one year through two years, Amount	77,979	0
Maturing one year through two years, Weighted rate	3.36%	0.00%
Maturing two years through three years, Amount	45,042	75,000
Maturing two years through three years, Weighted rate	2.99%	3.48%
Maturing three years through four years, Amount	0	45,000
Maturing three years through four years, Weighted rate	0.00%	2.99%
Maturing four years through five years, Amount	20,250	0
Maturing four years through five years, Weighted rate	2.83%	0.00%
Thereafter, Amount	137,827	157,013
Thereafter, Weighted rate	3.12%	3.07%
Total, Amount	$840,182	$997,013
Total, Weighted rate	1.21%	1.09%

Summary_of_FHLB_Put_Options_De

Summary of FHLB Put Options (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013
In Thousands, unless otherwise specified			FHLB Put Options
FHLB Put Options	'	'	'
Maturing during the year ended December 31, 2015, Amount	$77,979	$0	$75,000
Maturing during the year ended December 31, 2015, Interest rate	'	'	'3.16% - 3.64%
Maturing during the year ended December 31, 2016, Amount	45,042	75,000	45,000
Maturing during the year ended December 31, 2016, Interest rate	'	'	'2.93% - 3.05%
Maturing during the year ended December 31, 2018, Amount	20,250	0	20,000
Maturing during the year ended December 31, 2018, Interest rate	'	'	'2.73% - 2.85%
Maturing during the year ended December 31, 2021, Amount	137,827	157,013	135,000
Maturing during the year ended December 31, 2021, Interest rate	'	'	'2.88% - 3.43%
FHLB advances	$840,182	$997,013	$275,000

Borrowings_Details_Textual

Borrowings (Details Textual) (USD $)	Dec. 31, 2013	Dec. 31, 2012
FHLB Put Options	'	'
FHLB advances	$840,182,000	$997,013,000
Lines of Credit	'	'
Unsecured Lines of Credit	'	'
Lines of credit	255,000,000	'
FHLB Put Options	'	'
FHLB Put Options	'	'
FHLB advances	$275,000,000	'
Minimum rate to exercise put option	8.00%	'

Subordinated_Debentures_Detail

Subordinated Debentures (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013
In Thousands, unless otherwise specified			First Company Statutory Trust 2001	First Company Statutory Trust 2003	Glacier Capital Trust II	Citizens (ID) Statutory Trust I	Glacier Capital Trust III	Glacier Capital Trust IV	Bank of the San Juans Bancorporation Trust I
Terms of Subordinated Debentures	'	'	'	'	'	'	'	'	'
Balance	$125,562	$125,418	$3,018	$2,227	$46,393	$5,155	$36,083	$30,928	$1,758
Rate at December 31, 2013	'	'	3.54%	3.50%	2.99%	2.89%	1.53%	1.81%	2.06%
Variable Rate Structure	'	'	'3 mo LIBOR plus 3.30	'3 mo LIBOR plus 3.25	'3 mo LIBOR plus 2.75	'3 mo LIBOR plus 2.65	'3 mo LIBOR plus 1.29	'3 mo LIBOR plus 1.57	'3 mo LIBOR plus 1.82
LIBOR Rate Spread	'	'	3.30%	3.25%	2.75%	2.65%	1.29%	1.57%	1.82%
Maturity Date	'	'	31-Jul-31	26-Mar-33	7-Apr-34	17-Jun-34	7-Apr-36	15-Sep-36	1-Mar-37

Subordinated_Debentures_Detail1

Subordinated Debentures (Details Textual)	Dec. 31, 2013
Debt Instruments [Abstract]	'
Size of company eligible for Tier 1 grandfather provision	15,000,000,000

Interest_Rate_Swap_Summary_Det

Interest Rate Swap Summary (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013
Interest Rate Swap One	'
Interest rate swap derivative financial instruments	'
Forecasted Notional Amount	$160,000
Variable Interest Rate	'3 month LIBOR	[1]
Fixed Interest Rate	3.38%	[1]
Term, Effective Date	21-Oct-14	[2]
Term, Maturity Date	21-Oct-21	[2]
Interest Rate Swap Two	'
Interest rate swap derivative financial instruments	'
Forecasted Notional Amount	$100,000
Variable Interest Rate	'3 month LIBOR	[1]
Fixed Interest Rate	2.50%	[1]
Term, Effective Date	30-Nov-15	[2]
Term, Maturity Date	30-Nov-22	[2]
[1]	The Company pays the fixed interest rate and the counterparty pays the Company the variable interest rate.
[2]	No cash will be exchanged prior to the term.

Derivatives_and_Hedging_Activi2

Derivatives and Hedging Activities Offsetting Assets (Details) (Interest Rate Swap, USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Interest Rate Swap	'	'
Offsetting Derivative Assets	'	'
Gross Amounts of Recognized Assets	$6,844	$0
Gross Amounts Offset in the Statements of Financial Position	-4,948	0
Net Amounts of Assets Presented in the Statements of Financial Position	$1,896	$0

Derivatives_and_Hedging_Activi3

Derivatives and Hedging Activities Offsetting Liabilities (Details) (Interest Rate Swap, USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Interest Rate Swap	'	'
Offsetting Derivative Liabilities	'	'
Gross Amounts of Recognized Liabilities	$4,948	$16,832
Gross Amounts Offset in the Statements of Financial Position	-4,948	0
Net Amounts of Liabilities Presented in the Statements of Financial Position	$0	$16,832

Derivatives_and_Hedging_Activi4

Derivatives and Hedging Activities Derivatives and Hedging Activities (Details Textual) (USD $)	Dec. 31, 2013
Derivatives	'
Investment securities pledged to counterparties as collateral	$6,918,000
Collateral pledged from counterparties to the Company	$0

Regulatory_Capital_Details

Regulatory Capital (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Total capital (to risk-weighted assets)	'	'
Actual, Amount	$1,005,980	$923,574
Actual, Ratio	18.97%	20.09%
Minimum capital requirement, Amount	424,322	367,701
Minimum capital requirement, Ratio	8.00%	8.00%
Well capitalized requirement, Amount	530,402	459,627
Well capitalized requirement, Ratio	10.00%	10.00%
Tier 1 capital (to risk-weighted assets)	'	'
Actual, Amount	938,887	865,213
Actual, Ratio	17.70%	18.82%
Minimum capital requirement, Amount	212,161	183,851
Minimum capital requirement, Ratio	4.00%	4.00%
Well capitalized requirement, Amount	318,241	275,776
Well capitalized requirement, Ratio	6.00%	6.00%
Tier 1 capital (to average assets)	'	'
Actual, Amount	938,887	865,213
Actual, Ratio	12.11%	11.31%
Minimum capital requirement, Amount	310,082	306,005
Minimum capital requirement, Ratio	4.00%	4.00%
Glacier Bank	'	'
Total capital (to risk-weighted assets)	'	'
Actual, Amount	948,618	851,819
Actual, Ratio	17.93%	18.79%
Minimum capital requirement, Amount	423,235	362,711
Minimum capital requirement, Ratio	8.00%	8.00%
Well capitalized requirement, Amount	529,044	453,388
Well capitalized requirement, Ratio	10.00%	10.00%
Tier 1 capital (to risk-weighted assets)	'	'
Actual, Amount	881,692	794,228
Actual, Ratio	16.67%	17.52%
Minimum capital requirement, Amount	211,618	181,355
Minimum capital requirement, Ratio	4.00%	4.00%
Well capitalized requirement, Amount	317,426	272,033
Well capitalized requirement, Ratio	6.00%	6.00%
Tier 1 capital (to average assets)	'	'
Actual, Amount	881,692	794,228
Actual, Ratio	11.44%	10.55%
Minimum capital requirement, Amount	308,281	301,013
Minimum capital requirement, Ratio	4.00%	4.00%
Well capitalized requirement, Amount	$385,351	$376,267
Well capitalized requirement, Ratio	5.00%	5.00%

Regulatory_Capital_Details_Tex

Regulatory Capital (Details Textual)	Dec. 31, 2013	Dec. 31, 2012
Regulatory Capital	'	'
Percentage of total capital required for capital adequacy (to risk weighted assets)	8.00%	8.00%
Percentage of Tier 1 risk based capital required for capital adequacy (to risk weighted assets)	4.00%	4.00%
Percentage of Tier 1 leverage capital required for capital adequacy (to average assets)	4.00%	4.00%
Percentage of total capital required to be well capitalized (to risk weighted assets)	10.00%	10.00%
Percentage of Tier 1 risk based capital required to be well capitalized (to risk weighted assets)	6.00%	6.00%
Glacier Bank	'	'
Regulatory Capital	'	'
Percentage of total capital required for capital adequacy (to risk weighted assets)	8.00%	8.00%
Percentage of Tier 1 risk based capital required for capital adequacy (to risk weighted assets)	4.00%	4.00%
Percentage of Tier 1 leverage capital required for capital adequacy (to average assets)	4.00%	4.00%
Percentage of total capital required to be well capitalized (to risk weighted assets)	10.00%	10.00%
Percentage of Tier 1 risk based capital required to be well capitalized (to risk weighted assets)	6.00%	6.00%
Percentage of capital measures exceed the well capitalized threshold of leverage capital (to average assets)	5.00%	5.00%

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accumulated Other Comprehensive Income (Loss)	'	'
Net of Tax	$9,645	$47,962
Available-For-Sale Securities	'	'
Accumulated Other Comprehensive Income (Loss)	'	'
Before Tax	13,888	95,328
Tax effect	-5,403	-37,083
Net of Tax	8,485	58,245
Derivatives Used for Cash Flow Hedges	'	'
Accumulated Other Comprehensive Income (Loss)	'	'
Before Tax	1,896	-16,832
Tax effect	-736	6,549
Net of Tax	$1,160	($10,283)

Summary_of_Income_Tax_Expense_

Summary of Income Tax Expense (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current	'	'	'	'	'	'	'	'	'	'	'
Federal	'	'	'	'	'	'	'	'	$18,377	$12,718	$8,836
State	'	'	'	'	'	'	'	'	7,007	5,522	4,191
Total current income tax expense	'	'	'	'	'	'	'	'	25,384	18,240	13,027
Deferred	'	'	'	'	'	'	'	'	'	'	'
Federal	'	'	'	'	'	'	'	'	3,918	708	-11,256
State	'	'	'	'	'	'	'	'	715	129	-2,052
Total deferred income tax expense (benefit)	'	'	'	'	'	'	'	'	4,633	837	-13,308
Total income tax expense (benefit)	$8,630	$8,315	$5,927	$7,145	$5,853	$4,760	$3,843	$4,621	$30,017	$19,077	($281)

Summary_of_Effective_Tax_Rate_

Summary of Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Effective income tax rate reconciliation	'	'	'
Federal statutory rate	35.00%	35.00%	35.00%
State taxes, net of federal income tax benefit	4.00%	3.90%	8.10%
Tax-exempt interest income	-12.20%	-14.00%	-65.50%
Tax credits	-3.20%	-4.20%	-22.10%
Goodwill impairment charge	0.00%	0.00%	42.30%
Other, net	0.30%	-0.50%	0.60%
Effective tax rate	23.90%	20.20%	-1.60%

Deferred_Tax_Assets_and_Deferr

Deferred Tax Assets and Deferred Tax Liabilities (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred tax assets	'	'
Allowance for loan and lease losses	$50,652	$50,963
Other real estate owned	8,041	7,685
Deferred compensation	4,837	3,129
Employee benefits	3,132	2,715
Federal income tax credits	2,778	3,543
Interest rate swap agreements	0	6,549
Other	7,813	7,835
Total gross deferred tax assets	77,253	82,419
Deferred tax liabilities	'	'
FHLB stock dividends	-10,359	-10,143
Deferred loan costs	-6,058	-5,316
Available-for-sale securities	-5,402	-37,083
Depreciation of premises and equipment	-3,939	-5,437
Intangibles	-3,099	-1,117
Interest rate swap agreements	-736	0
Other	-4,111	-2,929
Total gross deferred tax liabilities	-33,704	-62,025
Net deferred tax asset	$43,549	$20,394

Years_Subject_to_Examination_D

Years Subject to Examination (Details)	12 Months Ended
	Dec. 31, 2013
Federal	'
Income Tax Examination	'
Income tax return jurisdictions and years that remain subject to examination	'2009, 2010, 2011 and 2012
Montana	'
Income Tax Examination	'
Income tax return jurisdictions and years that remain subject to examination	'2010, 2011 and 2012
Idaho	'
Income Tax Examination	'
Income tax return jurisdictions and years that remain subject to examination	'2009, 2010, 2011 and 2012
Colorado	'
Income Tax Examination	'
Income tax return jurisdictions and years that remain subject to examination	'2009, 2010, 2011 and 2012
Utah	'
Income Tax Examination	'
Income tax return jurisdictions and years that remain subject to examination	'2010, 2011 and 2012

Federal_and_State_Income_Taxes2

Federal and State Income Taxes (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Summary of Tax Credit Carryforwards	'	'
Federal income tax credit carryforwards expiration date	31-Dec-33	'
Income Tax Uncertainties	'	'
Unrecognized income tax benefit	$0	$0
Accrued liabilities for the payment of interest or penalties	0	0
Valuation Allowance	'	'
Deferred tax valuation allowance	0	0
Federal and State Income Taxes	'	'
Base year reserve for bad debts	$3,600,000	'

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Basic and Diluted Earnings Per Share	'	'	'	'	'	'	'	'	'	'	'
Net Income	$26,546	$25,628	$22,702	$20,768	$20,758	$19,444	$18,981	$16,333	$95,644	$75,516	$17,471
Average outstanding shares - basic	'	'	'	'	'	'	'	'	73,191,713	71,928,570	71,915,073
Add: dilutive stock options and awards	'	'	'	'	'	'	'	'	68,565	86	0
Average outstanding shares - diluted	'	'	'	'	'	'	'	'	73,260,278	71,928,656	71,915,073
Basic earnings per share	$0.36	$0.35	$0.31	$0.29	$0.29	$0.27	$0.26	$0.23	$1.31	$1.05	$0.24
Diluted earnings per share	$0.36	$0.35	$0.31	$0.29	$0.29	$0.27	$0.26	$0.23	$1.31	$1.05	$0.24
Earnings Per Share	'	'	'	'	'	'	'	'	'	'	'
Options excluded from the diluted average outstanding share calculation	'	'	'	'	'	'	'	'	38,915	879,525	1,567,561

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Benefit Plans	'	'	'
Minimum age required to be considered eligible for plan	21	'	'
Period of Employment Required to be Eligible for Plan	3	'	'
Minimum number of quarters required to be eligible for employer discretionary contribution	1	'	'
Minimum number of hours required to be considered eligible for employer discretionary contribution	501	'	'
Number of officers in employment contract	26	'	'
401(k) and Profit Sharing Plans	'	'	'
401(k) and Profit Sharing Plans	'	'	'
Percent rate for non-elective safe harbor contribution as component of profit sharing plan	3.00%	'	'
Profit Sharing Plan Expense	$5,862,000	$3,974,000	$2,043,000
Maximum percentage of annual compensation allowable for contribution by eligible employees	60.00%	'	'
Percentage of amount out of first specific percent of employee's contribution matched under plan	50.00%	'	'
Percentage of employee's contribution required to determine the matched amount under the plan	6.00%	'	'
Company's contribution to the plan	1,935,000	1,751,000	1,644,000
Deferred Compensation Plans	'	'	'
Deferred Compensation Plans	'	'	'
Percentage of salary for deferral of cash payments	50.00%	'	'
Percentage of bonuses and directors fees for deferral of cash payments	100.00%	'	'
Total amount deferred	376,000	278,000	362,000
Liability related to obligations of deferred compensation plans	5,042,000	1,255,000	'
Employee Benefit Plans	'	'	'
Credit earning rate as a percentage of return on equity	50.00%	'	'
Total earnings for the plan	515,000	231,000	54,000
Supplemental Employee Retirement Plan (SERP)	'	'	'
Employee Benefit Plans	'	'	'
Company's contribution to the plan	76,000	47,000	21,000
Credit earning rate as a percentage of return on equity	50.00%	'	'
Total earnings for the plan	$48,000	$37,000	$9,000

Summary_of_Stock_Option_Activi

Summary of Stock Option Activity (Details) (Stock Options, USD $)	12 Months Ended
	Dec. 31, 2013
Stock Options	'
Changes in shares granted for stock options for the year	'
Options outstanding, Beginning Balance	791,440
Options, Exercised	-281,560
Options, forfeited or expired	-451,070
Options outstanding, Ending Balance	58,810
Options, Exercisable	58,810
Weighted-Average Exercise Price	'
Options outstanding, Weighted Average Exercise Price, Beginning Balance	$16.95
Options, exercised, weighted average exercise price	$15.37
Options, forfeited or expired, weighted average exercise price	$18.14
Options outstanding, Weighted Average Exercise Price, Ending Balance	$15.47
Options exercisable, Weighted Average Exercise Price	$15.47

Stockbased_Compensation_Plans_1

Stock-based Compensation Plans Summary of Restricted Stock Award Activity (Details) (Restricted Stock, USD $)	12 Months Ended
	Dec. 31, 2013
Restricted Stock	'
Restricted stock award activity for the year	'
Restricted Stock Non-Vested, Beginning Balance	0
Restricted Stock, Granted	131,262
Restricted Stock, Vested	-11,753
Restricted Stock, Forfeited	-2,067
Restricted Stock Non-Vested, Ending Balance	117,442
Weighted-average grant date fair value	'
Restricted stock, weighted average grant date fair value, beginning balance	$0
Restricted stock, granted, weighted average grant date fair value	$16.76
Restricted stock, vested, weighted average grant date fair value	$16.76
Restricted stock, forfeited, weighted average grant date fair value	$16.76
Restricted stock, weighted average grant date fair value, ending balance	$16.76

Stockbased_Compensation_Plans_2

Stock-based Compensation Plans (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock-based Compensation Plans	'	'	'
Shares available to grant to employees and directors	4,116,931	'	'
Stock Options	'	'	'
Stock-based Compensation Plans	'	'	'
Compensation cost for stock compensation plans	$0	$4,000	$74,000
Income tax benefit from stock compensation plans	0	2,000	29,000
Stock Options	'	'	'
Expiration date of stock options granted	'5 years	'	'
Stock options granted during year	0	0	0
Unrecognized compensation cost, net of tax	0	'	'
Total intrinsic value of options exercised	1,907,000	3,000	0
Total intrinsic value of options exercised, tax benefit	742,000	1,000	0
Cash received from options exercised	4,327,000	81,000	0
Average remaining life on stock options outstanding	'1 month	'	'
Average remaining life on stock options exercisable	'1 month	'	'
Aggregate intrinsic value of stock options outstanding	842,000	'	'
Aggregate intrinsic value of stock options exercisable	842,000	'	'
Stock Options | Director	'	'	'
Stock Options	'	'	'
Requisite service period of stock options granted	'6 months	'	'
Stock Options | Employee	'	'	'
Stock Options	'	'	'
Requisite service period of stock options granted	'2 years	'	'
Restricted Stock	'	'	'
Stock-based Compensation Plans	'	'	'
Compensation cost for stock compensation plans	768,000	243,000	'
Income tax benefit from stock compensation plans	299,000	96,000	'
Restricted Stock Awards	'	'	'
Unrecognized compensation cost, net of tax	1,348,000	'	'
Unrecognized compensation costs, recognized over weighted-average period	'2 years 2 months 12 days	'	'
Fair value of shares vested	197,000	243,000	'
Tax benefit of shares vested	$77,000	$96,000	'

Parent_Statements_of_Financial

Parent Statements of Financial Condition (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Assets	'	'	'	'
Cash on hand and in banks	$109,995,000	$123,270,000	'	'
Interest bearing cash deposits	35,135,000	63,770,000	'	'
Cash and cash equivalents	155,657,000	187,040,000	'	'
Investment securities, available-for-sale	3,222,829,000	3,683,005,000	'	'
Other assets	55,251,000	41,969,000	'	'
Total assets	7,884,350,000	7,747,440,000	'	'
Liabilities and Stockholders' Equity	'	'	'	'
Subordinated debentures	125,562,000	125,418,000	'	'
Other liabilities	50,103,000	55,384,000	'	'
Total liabilities	6,921,100,000	6,846,491,000	'	'
Common stock	744,000	719,000	'	'
Paid-in capital	690,918,000	641,737,000	'	'
Retained earnings	261,943,000	210,531,000	'	'
Accumulated other comprehensive income	9,645,000	47,962,000	'	'
Total stockholders’ equity	963,250,000	900,949,000	850,227,000	838,204,000
Total liabilities and stockholders’ equity	7,884,350,000	7,747,440,000	'	'
Parent Company	'	'	'	'
Assets	'	'	'	'
Cash on hand and in banks	1,582,000	2,540,000	'	'
Interest bearing cash deposits	49,097,000	9,887,000	'	'
Cash and cash equivalents	50,679,000	12,427,000	'	'
Investment securities, available-for-sale	87,000	29,457,000	'	'
Other assets	9,050,000	23,221,000	'	'
Investment in subsidiaries	1,040,104,000	972,218,000	'	'
Total assets	1,099,920,000	1,037,323,000	'	'
Liabilities and Stockholders' Equity	'	'	'	'
Subordinated debentures	125,562,000	125,418,000	'	'
Other liabilities	11,108,000	10,956,000	'	'
Total liabilities	136,670,000	136,374,000	'	'
Common stock	744,000	719,000	'	'
Paid-in capital	690,918,000	641,737,000	'	'
Retained earnings	261,943,000	210,531,000	'	'
Accumulated other comprehensive income	9,645,000	47,962,000	'	'
Total stockholders’ equity	963,250,000	900,949,000	'	'
Total liabilities and stockholders’ equity	$1,099,920,000	$1,037,323,000	'	'

Parent_Statements_of_Operation

Parent Statements of Operations (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income	'	'	'	'	'	'	'	'	'	'	'
Loss on sale of investments	'	'	'	'	'	'	'	'	($299)	$0	$346
Expenses	'	'	'	'	'	'	'	'	'	'	'
Compensation and employee benefits	'	'	'	'	'	'	'	'	104,221	95,373	85,691
Other operating expenses	'	'	'	'	'	'	'	'	38,856	36,087	33,742
Total non-interest expense	53,034	50,368	48,481	43,434	48,008	50,178	46,190	49,045	195,317	193,421	232,124
Income tax benefit	-8,630	-8,315	-5,927	-7,145	-5,853	-4,760	-3,843	-4,621	-30,017	-19,077	281
Net Income	26,546	25,628	22,702	20,768	20,758	19,444	18,981	16,333	95,644	75,516	17,471
Parent Company	'	'	'	'	'	'	'	'	'	'	'
Income	'	'	'	'	'	'	'	'	'	'	'
Dividends from subsidiaries	'	'	'	'	'	'	'	'	65,445	78,209	43,450
Loss on sale of investments	'	'	'	'	'	'	'	'	-3,248	0	0
Other income	'	'	'	'	'	'	'	'	966	566	864
Intercompany charges for services	'	'	'	'	'	'	'	'	7,387	16,041	14,438
Total income	'	'	'	'	'	'	'	'	70,550	94,816	58,752
Expenses	'	'	'	'	'	'	'	'	'	'	'
Compensation and employee benefits	'	'	'	'	'	'	'	'	9,175	12,392	9,185
Other operating expenses	'	'	'	'	'	'	'	'	6,536	10,267	11,827
Total non-interest expense	'	'	'	'	'	'	'	'	15,711	22,659	21,012
Income Before Income Taxes	'	'	'	'	'	'	'	'	54,839	72,157	37,740
Income tax benefit	'	'	'	'	'	'	'	'	3,676	2,319	2,176
Income before equity in undistributed net income (loss) of subsidiaries	'	'	'	'	'	'	'	'	58,515	74,476	39,916
Equity in undistributed net income (loss) of subsidiaries	'	'	'	'	'	'	'	'	37,129	1,040	-22,825
Net Income	'	'	'	'	'	'	'	'	$95,644	$75,516	$17,091

Parent_Holding_Company_Informa2

Parent Holding Company Information Parent Statements of Comprehensive Income (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net Income	$26,546	$25,628	$22,702	$20,768	$20,758	$19,444	$18,981	$16,333	$95,644	$75,516	$17,471
Other Comprehensive (Loss) Income, Net of Tax	'	'	'	'	'	'	'	'	'	'	'
Unrealized (losses) gains on available-for-sale securities	'	'	'	'	'	'	'	'	-81,739	31,617	63,190
Reclassification adjustment for losses (gains) included in net income	'	'	'	'	'	'	'	'	299	0	-346
Net unrealized (losses) gains on securities	'	'	'	'	'	'	'	'	-81,440	31,617	62,844
Tax effect	'	'	'	'	'	'	'	'	31,680	-12,300	-24,444
Net of tax amount	'	'	'	'	'	'	'	'	-49,760	19,317	38,400
Unrealized gains (losses) on derivatives used for cash flow hedges	'	'	'	'	'	'	'	'	18,728	-7,926	-8,906
Tax effect	'	'	'	'	'	'	'	'	-7,285	3,084	3,465
Net of tax amount	'	'	'	'	'	'	'	'	11,443	-4,842	-5,441
Total other comprehensive (loss) income, net of tax	'	'	'	'	'	'	'	'	-38,317	14,475	32,959
Total Comprehensive Income	'	'	'	'	'	'	'	'	57,327	89,991	50,430
Parent Company	'	'	'	'	'	'	'	'	'	'	'
Net Income	'	'	'	'	'	'	'	'	95,644	75,516	17,091
Other Comprehensive (Loss) Income, Net of Tax	'	'	'	'	'	'	'	'	'	'	'
Unrealized (losses) gains on available-for-sale securities	'	'	'	'	'	'	'	'	-81,739	31,617	63,190
Reclassification adjustment for losses (gains) included in net income	'	'	'	'	'	'	'	'	299	0	-346
Net unrealized (losses) gains on securities	'	'	'	'	'	'	'	'	-81,440	31,617	62,844
Tax effect	'	'	'	'	'	'	'	'	31,680	-12,300	-24,444
Net of tax amount	'	'	'	'	'	'	'	'	-49,760	19,317	38,400
Unrealized gains (losses) on derivatives used for cash flow hedges	'	'	'	'	'	'	'	'	18,728	-7,926	-8,906
Tax effect	'	'	'	'	'	'	'	'	-7,285	3,084	3,465
Net of tax amount	'	'	'	'	'	'	'	'	11,443	-4,842	-5,441
Total other comprehensive (loss) income, net of tax	'	'	'	'	'	'	'	'	-38,317	14,475	32,959
Total Comprehensive Income	'	'	'	'	'	'	'	'	$57,327	$89,991	$50,050

Parent_Statements_of_Cash_Flow

Parent Statements of Cash Flows (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Activities	'	'	'
Net income	$95,644	$75,516	$17,471
Adjustments to reconcile net income to net cash provided by operating activities:	'	'	'
Loss on sale of investments	299	0	-346
Excess tax deficiencies from stock-based compensation	223	8	0
Net cash provided by operating activities	334,095	183,793	186,843
Investing Activities	'	'	'
Proceeds from sales, maturities and prepayments of investment securities, available-for-sale	1,864,334	2,041,416	1,024,508
Net addition of premises and equipment	-8,977	-10,730	-17,492
Net cash provided by (used in) investment activities	149,237	-579,646	-529,096
Financing Activities	'	'	'
Net increase in other borrowed funds	-1,502	180	-9,867
Cash dividends paid	-44,232	-47,472	-37,395
Excess tax deficiencies from stock-based compensation	-223	-8	0
Proceeds from stock options exercised	4,326	81	0
Net cash used in financing activities	-514,715	454,861	365,194
Net increase (decrease) in cash and cash equivalents	-31,383	59,008	22,941
Cash and cash equivalents at beginning of period	187,040	128,032	105,091
Cash and cash equivalents at end of period	155,657	187,040	128,032
Parent Company	'	'	'
Operating Activities	'	'	'
Net income	95,644	75,516	17,091
Adjustments to reconcile net income to net cash provided by operating activities:	'	'	'
Subsidiary income (in excess of) less than dividends distributed	-37,129	-1,040	22,825
Loss on sale of investments	3,248	0	0
Excess tax deficiencies from stock-based compensation	223	8	0
Net change in other assets and other liabilities	2,575	3,684	1,215
Net cash provided by operating activities	64,561	78,168	41,131
Investing Activities	'	'	'
Proceeds from sales, maturities and prepayments of investment securities, available-for-sale	26,561	787	1,376
Changes in investment securities and other stock - intercompany	-946	-19,183	0
Equity contribution to subsidiaries	-11,336	-28,500	-1,110
Net addition of premises and equipment	-603	-2,927	-1,920
Net cash provided by (used in) investment activities	13,676	-49,823	-1,654
Financing Activities	'	'	'
Net increase in other borrowed funds	144	143	143
Cash dividends paid	-44,232	-47,472	-37,395
Excess tax deficiencies from stock-based compensation	-223	-8	0
Proceeds from stock options exercised	4,326	81	0
Net cash used in financing activities	-39,985	-47,256	-37,252
Net increase (decrease) in cash and cash equivalents	38,252	-18,911	2,225
Cash and cash equivalents at beginning of period	12,427	31,338	29,113
Cash and cash equivalents at end of period	$50,679	$12,427	$31,338

Unaudited_Quarterly_Financial_2

Unaudited Quarterly Financial Data (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Summarized unaudited quarterly financial data	'	'	'	'	'	'	'	'	'	'	'
Interest income	$73,939	$69,531	$62,151	$57,955	$59,666	$62,015	$64,192	$67,884	$263,576	$253,757	$280,109
Interest expense	6,929	7,186	7,185	7,458	8,165	8,907	9,044	9,598	28,758	35,714	44,494
Net Interest Income	67,010	62,345	54,966	50,497	51,501	53,108	55,148	58,286	234,818	218,043	235,615
Provision for loan losses	1,802	1,907	1,078	2,100	2,275	2,700	7,925	8,625	6,887	21,525	64,500
Net interest income after provision for loan losses	65,208	60,438	53,888	48,397	49,226	50,408	47,223	49,661	227,931	196,518	171,115
Noninterest Income	23,002	23,873	23,222	22,950	25,393	23,974	21,791	20,338	93,047	91,496	78,199
Noninterest Expense	53,034	50,368	48,481	43,434	48,008	50,178	46,190	49,045	195,317	193,421	232,124
Income Before Income Taxes	35,176	33,943	28,629	27,913	26,611	24,204	22,824	20,954	125,661	94,593	17,190
Federal and state income tax expense	8,630	8,315	5,927	7,145	5,853	4,760	3,843	4,621	30,017	19,077	-281
Net Income	$26,546	$25,628	$22,702	$20,768	$20,758	$19,444	$18,981	$16,333	$95,644	$75,516	$17,471
Basic earnings per share	$0.36	$0.35	$0.31	$0.29	$0.29	$0.27	$0.26	$0.23	$1.31	$1.05	$0.24
Diluted earnings per share	$0.36	$0.35	$0.31	$0.29	$0.29	$0.27	$0.26	$0.23	$1.31	$1.05	$0.24

Fair_Value_Measurements_on_a_R

Fair Value Measurements on a Recurring Basis (Details) (Recurring measurements, USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financial Assets	'	'
Total assets measured at fair value on a recurring basis	$3,224,725	$3,683,005
Financial Liabilities	'	'
Total liabilities measured at fair value on a recurring basis	'	16,832
Interest rate swaps	'	'
Financial Liabilities	'	'
Interest rate swaps	'	16,832
U.S. government and federal agency	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	202
U.S. government sponsored enterprises	'	'
Financial Assets	'	'
Investment securities, available-for-sale	10,628	17,480
State and local governments	'	'
Financial Assets	'	'
Investment securities, available-for-sale	1,385,078	1,214,518
Corporate bonds	'	'
Financial Assets	'	'
Investment securities, available-for-sale	442,501	288,795
Collateralized debt obligations	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	1,708
Residential mortgage-backed securities	'	'
Financial Assets	'	'
Investment securities, available-for-sale	1,384,622	2,160,302
Interest rate swaps	'	'
Financial Assets	'	'
Interest rate swaps	1,896	'
Level 1	'	'
Financial Assets	'	'
Total assets measured at fair value on a recurring basis	0	0
Financial Liabilities	'	'
Total liabilities measured at fair value on a recurring basis	'	0
Level 1 | Interest rate swaps	'	'
Financial Liabilities	'	'
Interest rate swaps	'	0
Level 1 | U.S. government and federal agency	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	0
Level 1 | U.S. government sponsored enterprises	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 1 | State and local governments	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 1 | Corporate bonds	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 1 | Collateralized debt obligations	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	0
Level 1 | Residential mortgage-backed securities	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 1 | Interest rate swaps	'	'
Financial Assets	'	'
Interest rate swaps	0	'
Level 2	'	'
Financial Assets	'	'
Total assets measured at fair value on a recurring basis	3,224,725	3,683,005
Financial Liabilities	'	'
Total liabilities measured at fair value on a recurring basis	'	16,832
Level 2 | Interest rate swaps	'	'
Financial Liabilities	'	'
Interest rate swaps	'	16,832
Level 2 | U.S. government and federal agency	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	202
Level 2 | U.S. government sponsored enterprises	'	'
Financial Assets	'	'
Investment securities, available-for-sale	10,628	17,480
Level 2 | State and local governments	'	'
Financial Assets	'	'
Investment securities, available-for-sale	1,385,078	1,214,518
Level 2 | Corporate bonds	'	'
Financial Assets	'	'
Investment securities, available-for-sale	442,501	288,795
Level 2 | Collateralized debt obligations	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	1,708
Level 2 | Residential mortgage-backed securities	'	'
Financial Assets	'	'
Investment securities, available-for-sale	1,384,622	2,160,302
Level 2 | Interest rate swaps	'	'
Financial Assets	'	'
Interest rate swaps	1,896	'
Level 3	'	'
Financial Assets	'	'
Total assets measured at fair value on a recurring basis	0	0
Financial Liabilities	'	'
Total liabilities measured at fair value on a recurring basis	'	0
Level 3 | Interest rate swaps	'	'
Financial Liabilities	'	'
Interest rate swaps	'	0
Level 3 | U.S. government and federal agency	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	0
Level 3 | U.S. government sponsored enterprises	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 3 | State and local governments	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 3 | Corporate bonds	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 3 | Collateralized debt obligations	'	'
Financial Assets	'	'
Investment securities, available-for-sale	'	0
Level 3 | Residential mortgage-backed securities	'	'
Financial Assets	'	'
Investment securities, available-for-sale	0	0
Level 3 | Interest rate swaps	'	'
Financial Assets	'	'
Interest rate swaps	$0	'

Fair_Value_Measurements_on_a_N

Fair Value Measurements on a Non-Recurring Basis (Details) (Nonrecurring Measurements, USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets with a recorded change from re-measuring at fair value on a non-recurring basis	'	'
Other real estate owned	$10,888	$13,983
Collateral-dependent impaired loans, net of ALLL	18,670	22,966
Total assets measured at fair value on a non-recurring basis	29,558	36,949
Level 1	'	'
Assets with a recorded change from re-measuring at fair value on a non-recurring basis	'	'
Other real estate owned	0	0
Collateral-dependent impaired loans, net of ALLL	0	0
Total assets measured at fair value on a non-recurring basis	0	0
Level 2	'	'
Assets with a recorded change from re-measuring at fair value on a non-recurring basis	'	'
Other real estate owned	0	0
Collateral-dependent impaired loans, net of ALLL	0	0
Total assets measured at fair value on a non-recurring basis	0	0
Level 3	'	'
Assets with a recorded change from re-measuring at fair value on a non-recurring basis	'	'
Other real estate owned	10,888	13,983
Collateral-dependent impaired loans, net of ALLL	18,670	22,966
Total assets measured at fair value on a non-recurring basis	$29,558	$36,949

Fair_Value_of_Assets_and_Liabi2

Fair Value of Assets and Liabilities Quantitative Information about Level 3 Fair Value Measurements (Details) (Nonrecurring Measurements, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	29,558		36,949
Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	29,558		36,949
Other real estate owned | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	10,888		13,983
Other real estate owned | Cost Approach | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	'		93
Other real estate owned | Sales Comparison Approach | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	9,278		11,787
Other real estate owned | Combined Approach | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	1,610		2,103
Other real estate owned | Minimum Range | Cost Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	'		7.00%	[1]
Other real estate owned | Minimum Range | Sales Comparison Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	7.00%	[1]	7.00%	[1]
Adjustment to Comparables	0.00%	[1]	0.00%	[1]
Other real estate owned | Minimum Range | Combined Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	5.00%	[1]	5.00%	[1]
Discount Rate	8.50%	[1]	25.00%	[1]
Adjustment to Comparables	25.00%	[1]	0.00%	[1]
Other real estate owned | Maximum Range | Cost Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	'		7.00%	[1]
Other real estate owned | Maximum Range | Sales Comparison Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	10.00%	[1]	14.00%	[1]
Adjustment to Comparables	37.50%	[1]	37.00%	[1]
Other real estate owned | Maximum Range | Combined Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	10.00%	[1]	8.00%	[1]
Discount Rate	8.50%	[1]	25.00%	[1]
Adjustment to Comparables	25.00%	[1]	30.00%	[1]
Other real estate owned | Weighted Average Range | Cost Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	'		7.00%	[1]
Other real estate owned | Weighted Average Range | Sales Comparison Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	7.70%	[1]	7.90%	[1]
Adjustment to Comparables	1.40%	[1]	11.70%	[1]
Other real estate owned | Weighted Average Range | Combined Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	7.50%	[1]	6.60%	[1]
Discount Rate	8.50%	[1]	25.00%	[1]
Adjustment to Comparables	25.00%	[1]	7.70%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	18,670		22,966
Collateral-dependent Impaired Loans, Net of ALLL | Cost Approach | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	'		84
Collateral-dependent Impaired Loans, Net of ALLL | Income Approach | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	4,076		5,509
Collateral-dependent Impaired Loans, Net of ALLL | Sales Comparison Approach | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	11,784		12,878
Collateral-dependent Impaired Loans, Net of ALLL | Combined Approach | Level 3	'		'
Quantitative Information About Level 3 Fair Value Measurements	'		'
Fair Value	2,810		4,495
Collateral-dependent Impaired Loans, Net of ALLL | Minimum Range | Cost Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	'		8.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Minimum Range | Income Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	8.00%	[1]	8.00%	[1]
Discount Rate	8.30%	[1]	0.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Minimum Range | Sales Comparison Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	0.00%	[1]	0.00%	[1]
Adjustment to Comparables	0.00%	[1]	0.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Minimum Range | Combined Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	0.00%	[1]	8.00%	[1]
Discount Rate	7.30%	[1]	8.00%	[1]
Adjustment to Comparables	10.00%	[1]	0.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Maximum Range | Cost Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	'		8.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Maximum Range | Income Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	8.00%	[1]	10.00%	[1]
Discount Rate	8.30%	[1]	8.30%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Maximum Range | Sales Comparison Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	10.00%	[1]	16.00%	[1]
Adjustment to Comparables	1.00%	[1]	12.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Maximum Range | Combined Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	8.00%	[1]	10.00%	[1]
Discount Rate	7.30%	[1]	8.00%	[1]
Adjustment to Comparables	50.00%	[1]	36.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Weighted Average Range | Cost Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	'		8.00%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Weighted Average Range | Income Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	8.00%	[1]	8.20%	[1]
Discount Rate	8.30%	[1]	6.30%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Weighted Average Range | Sales Comparison Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	7.90%	[1]	8.60%	[1]
Adjustment to Comparables	0.00%	[1]	1.60%	[1]
Collateral-dependent Impaired Loans, Net of ALLL | Weighted Average Range | Combined Approach | Level 3	'		'
Unobservable Inputs	'		'
Selling Costs	7.80%	[1]	8.40%	[1]
Discount Rate	7.30%	[1]	8.00%	[1]
Adjustment to Comparables	18.90%	[1]	17.60%	[1]
[1]	The range for selling costs and adjustments to comparables indicate reductions to the fair value.

Carrying_Amount_and_Fair_Value

Carrying Amount and Fair Value of Financial Instruments (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Carrying Amount	'	'
Financial Assets	'	'
Cash and Cash Equivalents	$155,657	$187,040
Investment securities, available-for-sale	3,222,829	3,683,005
Loans Held-for-sale	46,738	145,501
Loans Receivable, net of ALLL	3,932,487	3,266,571
Accrued interest receivable	41,898	37,770
Non-marketable Equity Securities	52,192	48,812
Interest rate swaps	1,896	'
Total Financial Assets	7,453,697	7,368,699
Financial Liabilities	'	'
Deposits	5,579,967	5,364,461
FHLB advances	840,182	997,013
Repurchase agreements and other borrowed funds	321,781	299,540
Subordinated debentures	125,562	125,418
Accrued interest payable	3,505	4,675
Interest rate swaps	'	16,832
Total financial liabilities	6,870,997	6,807,939
Estimated Fair Value | Level 1	'	'
Financial Assets	'	'
Cash and Cash Equivalents	155,657	187,040
Investment securities, available-for-sale	0	0
Loans Held-for-sale	46,738	145,501
Loans Receivable, net of ALLL	0	0
Accrued interest receivable	41,898	37,770
Non-marketable Equity Securities	0	0
Interest rate swaps	0	'
Total Financial Assets	244,293	370,311
Financial Liabilities	'	'
Deposits	4,258,213	3,585,126
FHLB advances	0	0
Repurchase agreements and other borrowed funds	0	0
Subordinated debentures	0	0
Accrued interest payable	3,505	4,675
Interest rate swaps	'	0
Total financial liabilities	4,261,718	3,589,801
Estimated Fair Value | Level 2	'	'
Financial Assets	'	'
Cash and Cash Equivalents	0	0
Investment securities, available-for-sale	3,222,829	3,683,005
Loans Held-for-sale	0	0
Loans Receivable, net of ALLL	3,807,993	3,184,987
Accrued interest receivable	0	0
Non-marketable Equity Securities	52,192	48,812
Interest rate swaps	1,896	'
Total Financial Assets	7,084,910	6,916,804
Financial Liabilities	'	'
Deposits	1,341,382	1,789,134
FHLB advances	857,551	1,027,101
Repurchase agreements and other borrowed funds	321,781	299,540
Subordinated debentures	71,501	70,895
Accrued interest payable	0	0
Interest rate swaps	'	16,832
Total financial liabilities	2,592,215	3,203,502
Estimated Fair Value | Level 3	'	'
Financial Assets	'	'
Cash and Cash Equivalents	0	0
Investment securities, available-for-sale	0	0
Loans Held-for-sale	0	0
Loans Receivable, net of ALLL	187,731	186,201
Accrued interest receivable	0	0
Non-marketable Equity Securities	0	0
Interest rate swaps	0	'
Total Financial Assets	187,731	186,201
Financial Liabilities	'	'
Deposits	0	0
FHLB advances	0	0
Repurchase agreements and other borrowed funds	0	0
Subordinated debentures	0	0
Accrued interest payable	0	0
Interest rate swaps	'	0
Total financial liabilities	$0	$0

Contingencies_and_Commitments_1

Contingencies and Commitments (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Outstanding Commitments	'	'
Outstanding commitments	$881,550	$815,195
Commitments to Extend Credit	'	'
Outstanding Commitments	'	'
Outstanding commitments	866,885	802,595
Letters of Credit	'	'
Outstanding Commitments	'	'
Outstanding commitments	$14,665	$12,600

Consideration_Transferred_Iden

Consideration Transferred, Identifiable Net Assets Acquired and Goodwill Recognized (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair value of consideration transferred	'	'	'
Fair value of Company shares issued, net of equity issuance costs	$45,033	'	'
Cash consideration for outstanding shares	24,858	'	'
Total fair value of consideration transferred	69,891	'	'
Identifiable assets acquired	'	'	'
Cash and cash equivalents	51,013	'	'
Investment securities, available-for-sale	123,701	'	'
Loans receivable	387,185	'	'
Core deposit intangible	5,739	'	'
Accrued income and other assets	39,325	'	'
Total identifiable assets acquired	606,963	'	'
Liabilities assumed	'	'	'
Deposits	550,177	'	'
Federal Home Loan Bank advances and other borrowed funds	5,467	'	'
Accrued expenses and other liabilities	5,034	'	'
Total liabilities assumed	560,678	'	'
Total identifiable net assets	46,285	'	'
Goodwill recognized	23,606	0	0
Wheatland Bankshares	'	'	'
Fair value of consideration transferred	'	'	'
Fair value of Company shares issued, net of equity issuance costs	28,290	'	'
Cash consideration for outstanding shares	11,025	'	'
Total fair value of consideration transferred	39,315	'	'
Identifiable assets acquired	'	'	'
Cash and cash equivalents	23,148	'	'
Investment securities, available-for-sale	75,643	'	'
Loans receivable	171,199	'	'
Core deposit intangible	2,079	'	'
Accrued income and other assets	15,063	'	'
Total identifiable assets acquired	287,132	'	'
Liabilities assumed	'	'	'
Deposits	255,197	'	'
Federal Home Loan Bank advances and other borrowed funds	5,467	'	'
Accrued expenses and other liabilities	562	'	'
Total liabilities assumed	261,226	'	'
Total identifiable net assets	25,906	'	'
Goodwill recognized	13,409	'	'
North Cascades Bancshares	'	'	'
Fair value of consideration transferred	'	'	'
Fair value of Company shares issued, net of equity issuance costs	16,743	'	'
Cash consideration for outstanding shares	13,833	'	'
Total fair value of consideration transferred	30,576	'	'
Identifiable assets acquired	'	'	'
Cash and cash equivalents	27,865	'	'
Investment securities, available-for-sale	48,058	'	'
Loans receivable	215,986	'	'
Core deposit intangible	3,660	'	'
Accrued income and other assets	24,262	'	'
Total identifiable assets acquired	319,831	'	'
Liabilities assumed	'	'	'
Deposits	294,980	'	'
Federal Home Loan Bank advances and other borrowed funds	0	'	'
Accrued expenses and other liabilities	4,472	'	'
Total liabilities assumed	299,452	'	'
Total identifiable net assets	20,379	'	'
Goodwill recognized	$10,197	'	'

Pro_Forma_Summary_Details

Pro Forma Summary (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition, Pro Forma Information [Abstract]	'	'
Net interest income and non-interest income	$339,236	$334,317
Net income	$96,392	$80,403

Mergers_and_Acquisitions_Detai

Mergers and Acquisitions (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013
Business Acquisition	'
Business Combination, Consideration Transferred	$69,891,000
Cash consideration for outstanding shares	24,858,000
Core deposit intangible	5,739,000
Wheatland Bankshares	'
Business Acquisition	'
Effective Date of Acquisition	31-May-13
Percentage of Outstanding Common Stock Acquired	100.00%
Business Combination, Consideration Transferred	39,315,000
Number of Shares Issued for Aquisition	1,455,256
Cash consideration for outstanding shares	11,025,000
Loans receivable	171,199,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due	176,698,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due, Expected to be Uncollectible	0
Core deposit intangible	2,079,000
Core Deposit Intangible Assets, Weighted Average Useful Life	'11 years
Third-party Acquisition Related Costs	832,000
Net interest income and non-interest income	7,946,000
Net income	2,100,000
North Cascades Bancshares	'
Business Acquisition	'
Effective Date of Acquisition	31-Jul-13
Percentage of Outstanding Common Stock Acquired	100.00%
Business Combination, Consideration Transferred	30,576,000
Number of Shares Issued for Aquisition	687,876
Cash consideration for outstanding shares	13,833,000
Loans receivable	215,986,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due	223,949,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due, Expected to be Uncollectible	0
Core deposit intangible	3,660,000
Core Deposit Intangible Assets, Weighted Average Useful Life	'10 years
Third-party Acquisition Related Costs	667,000
Net interest income and non-interest income	6,837,000
Net income	$1,108,000

Subsequent_Event_Subsequent_Ev

Subsequent Event Subsequent Event (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Subsequent Event	'	'
Subsequent Event, Date	1-Jan-14	'
Subsequent Event, Description	'Reclassify investment securities from available-for-sale to held-to-maturity	'
Investment securities, available-for-sale	$3,222,829,000	$3,683,005,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments	49,801,000	101,778,000
State and local governments	'	'
Subsequent Event	'	'
Investment securities, available-for-sale	1,385,078,000	1,214,518,000
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments	31,621,000	88,095,000
Reclassification of AFS to HTM	'	'
Subsequent Event	'	'
Percent Available-For-Sale Prior to Reclassification	100.00%	'
Percent Available-For-Sale Subsequent to Reclassification	85.00%	'
Percent Held-To-Maturity Subsequent to Reclassification	15.00%	'
Reclassification of AFS to HTM | State and local governments	'	'
Subsequent Event	'	'
Investment securities, available-for-sale	484,583,000	'
Available-for-sale Securities, Gross Unrealized Gain Accumulated In Investments	$4,624,000	'