First Financial Bankshares (FFIN) 10-Q 4 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Nov. 04, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'FFIN	'
Entity Registrant Name	'FIRST FINANCIAL BANKSHARES INC	'
Entity Central Index Key	'0000036029	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	64,065,828

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
ASSETS	'	'	'
CASH AND DUE FROM BANKS	$149,957	$183,084	$164,666
FEDERAL FUNDS SOLD	4,785	3,430	14,300
INTEREST-BEARING DEPOSITS IN BANKS	83,994	25,498	48,634
Total cash and cash equivalents	238,736	212,012	227,600
INTEREST-BEARING TIME DEPOSITS IN BANKS	19,234	31,917	34,352
SECURITIES AVAILABLE-FOR-SALE, at fair value	2,253,762	2,057,723	1,975,303
SECURITIES HELD-TO-MATURITY (fair value of $560, $810 and $694 at September 30, 2014 and 2013, and December 31, 2013, respectively)	554	684	798
LOANS	'	'	'
Held for investment	2,828,430	2,684,285	2,609,085
Less - allowance for loan losses	-36,388	-33,900	-34,800
Net loans held for investment	2,792,042	2,650,385	2,574,285
Held for sale	11,266	5,163	5,724
Net loans	2,803,308	2,655,548	2,580,009
BANK PREMISES AND EQUIPMENT, net	101,437	95,505	94,676
INTANGIBLE ASSETS	97,429	97,485	97,429
OTHER ASSETS	61,351	71,334	65,468
Total assets	5,575,811	5,222,208	5,075,635
LIABILITIES AND SHAREHOLDERS' EQUITY	'	'	'
NONINTEREST-BEARING DEPOSITS	1,505,847	1,362,184	1,371,835
INTEREST-BEARING DEPOSITS	2,958,517	2,772,891	2,628,722
Total deposits	4,464,364	4,135,075	4,000,557
DIVIDENDS PAYABLE	8,969	8,318	8,314
SHORT-TERM BORROWINGS	341,909	463,888	466,500
OTHER LIABILITIES	101,804	27,280	32,023
Total liabilities	4,917,046	4,634,561	4,507,394
COMMITMENTS AND CONTINGENCIES	'	'	'
SHAREHOLDERS' EQUITY	'	'	'
Common stock - $0.01 par value, authorized 80,000,000 shares; 64,065,828, 31,977,670, and 31,992,497 shares issued at September 30, 2014 and 2013, and December 31, 2013, respectively	641	320	320
Capital surplus	304,866	302,991	302,320
Retained earnings	314,363	273,972	261,052
Treasury stock (shares at cost: 532,256, 269,334, and 269,467 at September 30, 2014 and 2013, and December 31, 2013, respectively)	-5,797	-5,490	-5,364
Deferred compensation	5,797	5,490	5,364
Accumulated other comprehensive earnings	38,895	10,364	4,549
Total shareholders' equity	658,765	587,647	568,241
Total liabilities and shareholders' equity	$5,575,811	$5,222,208	$5,075,635

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'	'
SECURITIES HELD-TO-MATURITY, fair value	$560	$694	$810
Common stock, par value	$0.01	$0.01	$0.01
Common stock, shares authorized	80,000,000	80,000,000	80,000,000
Common stock, shares issued	64,065,828	31,992,497	31,977,670
Treasury stock, shares	532,256	269,467	269,334

Consolidated_Statements_of_Ear

Consolidated Statements of Earnings (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
INTEREST INCOME:	'	'	'	'
Interest and fees on loans	$34,682	$32,936	$101,586	$88,260
Interest on investment securities:	'	'	'	'
Taxable	6,858	6,130	21,032	18,818
Exempt from federal income tax	8,335	7,480	24,543	21,122
Interest on federal funds sold and interest-bearing deposits in banks	80	109	257	405
Total interest income	49,955	46,655	147,418	128,605
INTEREST EXPENSE:	'	'	'	'
Interest on deposits	999	1,038	2,894	2,758
Other	70	126	249	256
Total interest expense	1,069	1,164	3,143	3,014
Net interest income	48,886	45,491	144,275	125,591
PROVISION FOR LOAN LOSSES	896	1,349	3,710	2,582
Net interest income after provision for loan losses	47,990	44,142	140,565	123,009
NONINTEREST INCOME:	'	'	'	'
Trust fees	4,772	4,138	13,897	11,884
Service charges on deposit accounts	4,402	4,798	12,623	13,009
ATM, interchange and credit card fees	5,093	4,404	14,291	12,315
Real estate mortgage operations	1,813	2,008	4,174	5,149
Net gain (loss) on sale of available-for-sale securities (includes $1 and ($108) for the three months ended September 30, 2014 and 2013, respectively, and ($4) and $147 for the nine months ended September 30, 2014 and 2013, respectively, related to accumulated other comprehensive earnings reclassification	1	-108	-4	147
Net gain (loss) on sale of foreclosed assets	305	36	804	-263
Other	938	1,799	3,816	4,019
Total noninterest income	17,324	17,075	49,601	46,260
NONINTEREST EXPENSE:	'	'	'	'
Salaries and employee benefits	17,950	17,501	52,638	48,831
Net occupancy expense	2,297	2,164	6,804	5,995
Equipment expense	2,758	2,490	8,045	7,146
FDIC insurance premiums	693	640	2,035	1,781
ATM, interchange and credit card expenses	1,819	1,474	4,995	4,161
Professional and service fees	1,205	1,363	3,249	3,198
Printing, stationery and supplies	632	534	1,960	1,504
Amortization of intangible assets	62	77	210	120
Other	6,624	9,291	21,553	20,181
Total noninterest expense	34,040	35,534	101,489	92,917
EARNINGS BEFORE INCOME TAXES	31,274	25,683	88,677	76,352
INCOME TAX EXPENSE (includes $0 and ($38) for the three months ended September 30, 2014 and 2013, respectively, and ($1) and $51 for the nine months ended September 30, 2014 and 2013, respectively, related to income tax expense from reclassification items)	7,843	6,121	21,705	18,723
NET EARNINGS	$23,431	$19,562	$66,972	$57,629
EARNINGS PER SHARE, BASIC	$0.37	$0.31	$1.05	$0.91
EARNINGS PER SHARE, ASSUMING DILUTION	$0.36	$0.30	$1.04	$0.90
DIVIDENDS PER SHARE	$0.14	$0.13	$0.41	$0.39

Consolidated_Statements_of_Ear1

Consolidated Statements of Earnings (Unaudited) (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]	'	'	'	'
Reclassification adjustment for realized gains on investment securities included in net earnings (loss), before income tax	$1	($108)	($4)	$147
Income tax expense from reclassification items	$0	($38)	($1)	$51

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Earnings (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Amounts Reclassified Out Of Accumulated Other Comprehensive Income Loss [Abstract]	'	'	'	'
NET EARNINGS	$23,431	$19,562	$66,972	$57,629
OTHER ITEMS OF COMPREHENSIVE EARNINGS:	'	'	'	'
Change in unrealized gain (loss) on investment securities available-for-sale, before income taxes	5,707	-29,688	43,889	-71,791
Reclassification adjustment for realized losses (gains) on investment securities included in net earnings, before income tax	-1	108	4	-147
Total other items of comprehensive earnings (losses)	5,706	-29,580	43,893	-71,938
Income tax benefit (expense) related to other items of comprehensive earnings	-1,997	10,352	-15,362	25,178
COMPREHENSIVE EARNINGS:	$27,140	$334	$95,503	$10,869

Consolidated_Statements_of_Sha

Consolidated Statements of Shareholders' Equity (USD $)	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Deferred Compensation [Member]	Accumulated Other Comprehensive Earnings [Member]
In Thousands, except Share data
Beginning Balance at Dec. 31, 2012	$556,963	$315	$277,412	$227,927	($5,007)	$5,007	$51,309
Beginning Balance, shares at Dec. 31, 2012	'	31,496,881	'	'	-266,845	'	'
Net earnings (unaudited)	57,629	'	'	57,629	'	'	'
Stock issued in acquisition of Orange Savings Bank, SSB (unaudited)	23,100	4	23,096	'	'	'	'
Stock issued in acquisition of Orange Savings Bank, SSB, shares (unaudited)	'	420,000	'	'	'	'	'
Stock option exercises (unaudited)	1,519	1	1,518	'	'	'	'
Stock option exercises, shares (unaudited)	'	60,789	'	'	'	'	'
Cash dividends declared (unaudited)	-24,504	'	'	-24,504	'	'	'
Change in unrealized gain in investment securities available-for-sale, net of related income taxes (unaudited)	-46,760	'	'	'	'	'	-46,760
Additional tax benefit related to directors' deferred compensation plan (unaudited)	30	'	30	'	'	'	'
Shares purchased in connection with directors' deferred compensation plan, net (unaudited)	'	'	'	'	-357	357	'
Shares purchased in connection with directors' deferred compensation plan, net, shares (unaudited)	'	'	'	'	-2,489	'	'
Stock option expense (unaudited)	264	'	264	'	'	'	'
Ending Balance (unaudited) at Sep. 30, 2013	568,241	320	302,320	261,052	-5,364	5,364	4,549
Ending Balance, shares (unaudited) at Sep. 30, 2013	'	31,977,670	'	'	-269,334	'	'
Beginning Balance at Dec. 31, 2013	587,647	320	302,991	273,972	-5,490	5,490	10,364
Beginning Balance, shares at Dec. 31, 2013	'	31,992,497	'	'	-269,467	'	'
Net earnings (unaudited)	66,972	'	'	66,972	'	'	'
Stock option exercises (unaudited)	1,077	1	1,076	'	'	'	'
Stock option exercises, shares (unaudited)	'	50,571	'	'	'	'	'
Cash dividends declared (unaudited)	-26,261	'	'	-26,261	'	'	'
Change in unrealized gain in investment securities available-for-sale, net of related income taxes (unaudited)	28,531	'	'	'	'	'	28,531
Additional tax benefit related to directors' deferred compensation plan (unaudited)	267	'	267	'	'	'	'
Shares purchased in connection with directors' deferred compensation plan, net (unaudited)	'	'	'	'	-307	307	'
Shares purchased in connection with directors' deferred compensation plan, net, shares (unaudited)	'	'	'	'	5,345	'	'
Stock option expense (unaudited)	532	'	532	'	'	'	'
Two-for-one stock split in the form of a 100% stock dividend (unaudited)	'	320	'	-320	'	'	'
Two-for-one stock split in the form of a 100% stock dividend, shares (unaudited)	'	32,022,760	'	'	-268,134	'	'
Ending Balance (unaudited) at Sep. 30, 2014	$658,765	$641	$304,866	$314,363	($5,797)	$5,797	$38,895
Ending Balance, shares (unaudited) at Sep. 30, 2014	'	64,065,828	'	'	532,256	'	'

Consolidated_Statements_of_Sha1

Consolidated Statements of Shareholders' Equity (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash dividends per share (unaudited)	$0.41	$0.39
Percentage of Stock dividend (unaudited)	100.00%	'
Common Stock [Member]	'	'
Percentage of Stock dividend (unaudited)	100.00%	'
Retained Earnings [Member]	'	'
Cash dividends per share (unaudited)	$0.41	$0.39
Percentage of Stock dividend (unaudited)	100.00%	'

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
CASH FLOWS FROM OPERATING ACTIVITIES:	'	'
NET EARNINGS	$66,972	$57,629
Adjustments to reconcile net earnings to net cash provided by operating activities:	'	'
Depreciation and amortization	6,244	6,376
PROVISION FOR LOAN LOSSES	3,710	2,582
Securities premium amortization (discount accretion), net	14,739	13,680
Gain on sale of assets, net	-815	-62
Deferred federal income tax benefit	-844	-309
Change in loans held for sale	-6,103	5,731
Change in other assets	8,936	2,642
Change in other liabilities	6,721	5,996
Total adjustments	32,588	36,636
Net cash provided by operating activities	99,560	94,265
CASH FLOWS FROM INVESTING ACTIVITIES:	'	'
Cash paid for acquisition of Orange Savings Bank, SSB, less cash acquired	'	-25,706
Net decrease in interest-bearing time deposits in banks	12,683	14,653
Activity in available-for-sale securities:	'	'
Sales	3,590	121,420
Maturities	1,677,839	248,750
Purchases	-1,794,233	-511,471
Activity in held-to-maturity securities - maturities	130	263
Net increase in loans	-146,452	-242,860
Purchases of bank premises and equipment and other assets	-12,993	-8,492
Proceeds from sale of other assets	3,823	1,885
Net cash used in investing activities	-255,613	-401,558
CASH FLOWS FROM FINANCING ACTIVITIES:	'	'
Net increase (decrease) in noninterest-bearing deposits	143,663	-7,402
Net increase (decrease) in interest-bearing deposits	185,626	-10,575
Net increase (decrease) in short-term borrowings	-121,979	206,803
Common stock transactions:	'	'
Proceeds from stock issuances	1,076	1,519
Dividends paid	-25,609	-16,191
Net cash provided by financing activities	182,777	174,154
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	26,724	-133,139
CASH AND CASH EQUIVALENTS, beginning of period	212,012	360,739
CASH AND CASH EQUIVALENTS, end of period	238,736	227,600
SUPPLEMENTAL INFORMATION AND NONCASH TRANSACTIONS	'	'
Interest paid	3,155	2,988
Federal income tax paid	21,281	17,386
Transfer of loans to foreclosed assets	1,085	1,610
Investment securities purchased but not settled	$61,332	$3,496

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Basis of Presentation	'
	Note 1 - Basis of Presentation
	The unaudited interim consolidated financial statements include the accounts of the Company, a Texas corporation and a financial holding company registered under the Bank Holding Company Act of 1956, as amended, or BHCA, and its wholly-owned subsidiaries: First Financial Bank, National Association, Abilene, Texas; First Technology Services, Inc.; First Financial Trust & Asset Management Company, National Association; First Financial Investments, Inc.; and First Financial Insurance Agency, Inc.
	Through our subsidiary bank, we conduct a full-service commercial banking business. Our banking centers are located primarily in Central, North Central, Southeast and West Texas. As of September 30, 2014, we had 62 financial centers across Texas, with eleven locations in Abilene, three locations in San Angelo and Weatherford, two locations in Cleburne, Stephenville and Granbury, and one location each in Acton, Albany, Aledo, Alvarado, Beaumont, Boyd, Bridgeport, Brock, Burleson, Cisco, Clyde, Decatur, Eastland, Fort Worth, Glen Rose, Grapevine, Hereford, Huntsville, Keller, Mauriceville, Merkel, Midlothian, Mineral Wells, Moran, New Waverly, Newton, Odessa, Orange, Port Arthur, Ranger, Rising Star, Roby, Southlake, Sweetwater, Trent, Trophy Club, Vidor, Waxahachie, and Willow Park. Our trust subsidiary has eight locations which are located in Abilene, Fort Worth, Lubbock, Odessa, Orange, San Angelo, Stephenville and Sweetwater, all in Texas.
	In the opinion of management, the unaudited interim consolidated financial statements reflect all adjustments necessary for a fair presentation of the Company’s financial position and unaudited results of operations and should be read in conjunction with the Company’s audited consolidated financial statements, and notes thereto in the Company’s Annual Report on Form 10-K, for the year ended December 31, 2013. All adjustments were of a normal recurring nature. However, the results of operations for the three and nine months ended September 30, 2014, are not necessarily indicative of the results to be expected for the year ending December 31, 2014, due to seasonality, changes in economic conditions and loan credit quality, interest rate fluctuations, regulatory and legislative changes and other factors. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States have been condensed or omitted under U. S. Securities and Exchange Commission (“SEC”) rules and regulations. The Company evaluated subsequent events for potential recognition and/or disclosure through the date the consolidated financial statements were issued.
	On May 31, 2013, the Company acquired 100% of the outstanding capital stock of Orange Savings Bank, SSB, a wholly-owned subsidiary of OSB Financial Services, Inc. The results of operations of Orange Savings Bank, SSB, subsequent to the acquisition date, are included in the consolidated earnings of the Company.
	On October 28, 2014, the Company’s Board of Directors authorized the repurchase of up to 1,500,000 common shares through September 30, 2017. The stock buyback plan authorizes management to repurchase the stock at such time as repurchases are considered beneficial to shareholders. Any repurchase of stock will be made through the open market, block trades or in privately negotiated transactions in accordance with applicable laws and regulations. Under the repurchase plan, there is no minimum number of shares that the Company is required to repurchase. Through September 30, 2014, no shares have been repurchased under the prior authorization that expired September 30, 2014.
	Goodwill and other intangible assets are evaluated annually for impairment as of the end of the second quarter. No such impairment has been noted in connection with the current or any prior evaluations.

Stock_Split

Stock Split	9 Months Ended
	Sep. 30, 2014
Text Block [Abstract]	'
Stock Split	'
	Note 2 - Stock Split
	On April 22, 2014, the Company’s Board of Directors declared a two-for-one stock split in the form of a 100% stock dividend effective for shareholders of record on May 15, 2014 that was distributed on June 2, 2014. All per share amounts in this report have been restated to reflect this stock split. An amount equal to the par value of the additional common shares issued pursuant to the stock split was reflected as a transfer from retained earnings to common stock on the consolidated financial statements as of and for the nine months ended September 30, 2014.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Note 3 - Earnings Per Share
	Basic earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of shares outstanding during the periods presented. In computing diluted earnings per common share for the three and nine months ended September 30, 2014 and 2013, the Company assumes that all dilutive outstanding options to purchase common stock have been exercised at the beginning of the period (or the time of issuance, if later). The dilutive effect of the outstanding options is reflected by application of the treasury stock method, whereby the proceeds from the exercised options are assumed to be used to purchase common stock at the average market price during the respective periods. The weighted average common shares outstanding used in computing basic earnings per common share for the three months ended September 30, 2014 and 2013 were 64,059,675 and 63,940,810 shares, respectively. The weighted average common shares outstanding used in computing basic earnings per common share for the nine months ended September 30, 2014 and 2013 were 64,038,526 and 63,444,544 shares, respectively. The weighted average common shares outstanding used in computing fully diluted earnings per common share for the three months ended September 30, 2014 and 2013 were 64,304,985 and 64,243,542 shares, respectively. The weighted average common shares outstanding used in computing fully diluted earnings per common share for the nine months ended September 30, 2014 and 2013 were 64,302,615 and 63,706,588 shares, respectively.

Interestbearing_Time_Deposits_

Interest-bearing Time Deposits in Banks and Securities	9 Months Ended
	Sep. 30, 2014
Cash and Cash Equivalents [Abstract]	'
Interest-bearing Time Deposits in Banks and Securities	'
	Note 4 - Interest-bearing Time Deposits in Banks and Securities
	Interest-bearing time deposits in banks totaled $19,234,000 and $31,917,000 at September 30, 2014 and December 31, 2013, respectively, and have original maturities generally ranging from one to two years. Of these amounts, $17,699,000 and $29,002,000 are time deposits with balances greater than $100,000 at September 30, 2014 and December 31, 2013, respectively.
	Management classifies debt and equity securities as held-to-maturity, available-for-sale, or trading based on its intent. Debt securities that management has the positive intent and ability to hold to maturity are classified as held-to-maturity and recorded at cost, adjusted for amortization of premiums and accretion of discounts, which are recognized as adjustments to interest income using the interest method. Securities not classified as held-to-maturity or trading are classified as available-for-sale and recorded at fair value, with all unrealized gains and unrealized losses judged to be temporary, net of deferred income taxes, excluded from earnings and reported in the consolidated statements of comprehensive earnings. Available-for-sale securities that have unrealized losses that are judged other-than-temporary are included in gain (loss) on sale of securities and a new cost basis is established. Securities classified as trading are recorded at fair value with unrealized gains and losses included in earnings.
	The Company records its available-for-sale and trading securities portfolio at fair value. Fair values of these securities are determined based on methodologies in accordance with current authoritative accounting guidance. Fair values are volatile and may be influenced by a number of factors, including market interest rates, prepayment speeds, discount rates, credit ratings and yield curves. Fair values for investment securities are based on quoted market prices, where available. If quoted market prices are not available, fair values are based on the quoted prices of similar instruments or an estimate of fair value by using a range of fair value estimates in the market place as a result of the illiquid market specific to the type of security.
	When the fair value of a security is below its amortized cost, and depending on the length of time the condition exists and the extent the fair value is below amortized cost, additional analysis is performed to determine whether an other-than-temporary impairment condition exists. Available-for-sale and held-to-maturity securities are analyzed quarterly for possible other-than-temporary impairment. The analysis considers (i) whether we have the intent to sell our securities prior to recovery and/or maturity, (ii) whether it is more likely than not that we will have to sell our securities prior to recovery and/or maturity, (iii) the length of time and extent to which the fair value has been less than amortized cost, and (iv) the financial condition of the issuer. Often, the information available to conduct these assessments is limited and rapidly changing, making estimates of fair value subject to judgment. If actual information or conditions are different than estimated, the extent of the impairment of the security may be different than previously estimated, which could have a material effect on the Company’s results of operations and financial condition.
	The Company’s investment portfolio consists of obligations of U. S. government sponsored-enterprises and agencies, mortgage pass-through securities, corporate bonds and general obligation or revenue based municipal bonds. Pricing for such securities is generally readily available and transparent in the market. The Company utilizes independent third party pricing services to value its investment securities, which the Company reviews as well as the underlying pricing methodologies for reasonableness and to ensure such prices are aligned with pricing matrices. The Company validates quarterly, on a sample basis, prices supplied by the independent pricing services by comparison to prices obtained from other third party sources.
	A summary of the Company’s available-for-sale securities follows (in thousands):
		September 30, 2014
		Amortized		Gross		Gross			Estimated
		Cost Basis		Unrealized		Unrealized			Fair Value
				Holding Gains		Holding Losses
	U.S. Treasury securities	$	520	$	—	$	—		$	520
	Obligations of U.S. government sponsored enterprises and agencies		106,339		964		(2	)		107,301
	Obligations of states and political subdivisions		1,046,148		56,398		(577	)		1,101,969
	Corporate bonds and other		96,424		3,269		—			99,693
	Residential mortgage-backed securities		803,072		14,395		(5,600	)		811,867
	Commercial mortgage-backed securities		134,769		31		(2,388	)		132,412
	Total securities available-for-sale	$	2,187,272	$	75,057	$	(8,567	)	$	2,253,762
		31-Dec-13
		Amortized		Gross		Gross			Estimated
		Cost Basis		Unrealized		Unrealized			Fair Value
				Holding Gains		Holding Losses
	Obligations of U.S. government sponsored-enterprises and agencies	$	136,416	$	1,672	$	—		$	138,088
	Obligations of states and political subdivisions		974,608		27,980		(11,319	)		991,269
	Corporate bonds and other		105,490		3,550		—			109,040
	Residential mortgage-backed securities		706,289		12,253		(7,922	)		710,620
	Commercial mortgage-backed securities		112,323		—		(3,617	)		108,706
	Total securities available-for-sale	$	2,035,126	$	45,455	$	(22,858	)	$	2,057,723
	Disclosures related to the Company’s held-to-maturity securities, which totaled $554,000 and $684,000 at September 30, 2014 and December 31, 2013, respectively, have not been presented due to insignificance.
	The Company invests in mortgage-backed securities that have expected maturities that differ from their contractual maturities. These differences arise because borrowers may have the right to call or prepay these obligations with or without a prepayment penalty. These securities include collateralized mortgage obligations (CMOs) and other asset backed securities. The expected maturities of these securities at September 30, 2014 were computed by using scheduled amortization of balances and historical prepayment rates.
	The amortized cost and estimated fair value of available-for-sale securities at September 30, 2014, by contractual or expected maturity, as applicable, are shown below (in thousands):
		Amortized		Estimated
		Cost Basis		Fair Value
	Due within one year	$	76,858	$	77,722
	Due after one year through five years		663,151		695,484
	Due after five years through ten years		502,028		527,658
	Due after ten years		7,394		8,619
	Mortgage-backed securities		937,841		944,279
	Total	$	2,187,272	$	2,253,762
	The following tables disclose, as of September 30, 2014 and December 31, 2013, the Company’s investment securities that have been in a continuous unrealized-loss position for less than 12 months and for 12 months or longer (in thousands):
		Less than 12 Months				12 Months or Longer					Total
	September 30, 2014	Fair Value		Unrealized		Fair Value			Unrealized		Fair Value		Unrealized
				Loss					Loss				Loss
	Obligations of U.S. Government sponsored enterprises and Agencies	$	876	$	2	$	—		$	—	$	876	$	2
	Obligations of states and political subdivisions		17,871		38		50,158			539		68,029		577
	Residential mortgage-backed securities		82,382		450		134,271			5,150		216,653		5,600
	Commercial mortgage-backed securities		6,435		15		102,353			2,373		108,788		2,388
	Total	$	107,564	$	505	$	286,782		$	8,062	$	394,346	$	8,567
		Less than 12 Months				12 Months or Longer					Total
	December 31, 2013	Fair Value		Unrealized		Fair			Unrealized		Fair Value		Unrealized
				Loss		Value			Loss				Loss
	Obligations of states and political subdivisions	$	316,394	$	10,973	$	4,153		$	346	$	320,547	$	11,319
	Residential mortgage-backed securities		228,423		7,623		5,624			299		234,047		7,922
	Commercial mortgage-backed securities		108,706		3,617		—			—		108,706		3,617
	Total	$	653,523	$	22,213	$	9,777		$	645	$	663,300	$	22,858
	The number of investments in an unrealized loss position totaled 114 at September 30, 2014. We do not believe these unrealized losses are “other-than-temporary” as (i) we do not have the intent to sell our securities prior to recovery and/or maturity and (ii) it is more likely than not that we will not have to sell our securities prior to recovery and/or maturity. In making the determination, we also consider the length of time and extent to which fair value has been less than cost and the financial condition of the issuer. The unrealized losses noted are interest rate related due to the level of interest rates at September 30, 2014 compared to the time of purchase. We have reviewed the ratings of the issuers and have not identified any issues related to the ultimate repayment of principal as a result of credit concerns on these securities. Our mortgage related securities are backed by GNMA, FNMA and FHLMC or are collateralized by securities backed by these agencies.
	At September 30, 2014, $1,430,183,000 of the Company’s securities were pledged as collateral for public or trust fund deposits, repurchase agreements and for other purposes required or permitted by law.
	During the third quarter ended September 30, 2014 and 2013, sales and calls of investment securities that were classified as available-for-sale totaled $2,145,000 and $50,065,000, respectively. Gross realized gains from security sales and calls during the third quarter of 2014 and 2013 totaled $1,000 and $1,114,000, respectively. Gross realized losses from security sales and calls during the third quarter of 2013 totaled $1,222,000. There were no gross realized losses from security sales or calls in the third quarter of 2014. During the nine months ended September 30, 2014 and 2013, sales and calls of investment securities that were classified as available-for-sale totaled $3,590,000 and $121,420,000, respectively. Gross realized gains from security sales and calls during the nine month periods ended September 30, 2014 and 2013 totaled $1,000 and $1,371,000, respectively. Gross realized losses from security sales and calls during the nine month periods ended September 30, 2014 and 2013 totaled $5,000 and $1,224,000, respectively. The specific identification method was used to determine cost in order to compute the realized gains and losses.

Loans_and_Allowance_for_Loan_L

Loans and Allowance for Loan Losses	9 Months Ended
	Sep. 30, 2014
Receivables [Abstract]	'
Loans and Allowance for Loan Losses	'
	Note 5 - Loans and Allowance for Loan Losses
	Loans held for investment are stated at the amount of unpaid principal, reduced by unearned income and an allowance for loan losses. Interest on loans is calculated by using the simple interest method on daily balances of the principal amounts outstanding. The Company defers and amortizes net loan origination fees and costs as an adjustment to yield. The allowance for loan losses is established through a provision for loan losses charged to expense. Loans are charged against the allowance for loan losses when management believes the collectability of the principal is unlikely.
	The Company has lending policies and procedures in place that are designed to maximize loan income with an acceptable level of risk. Management reviews and approves these policies and procedures on an annual basis and makes changes as appropriate. Management receives and reviews monthly reports related to loan originations, quality, concentrations, delinquencies, nonperforming and potential problem loans. Diversification in the loan portfolio is a means of managing risk associated with fluctuations in economic conditions, both by type of loan and geographic location.
	Commercial loans are underwritten after evaluating and understanding the borrower’s ability to operate profitably and effectively. Underwriting standards are designed to determine whether the borrower possesses sound business ethics and practices and to evaluate current and projected cash flows to determine the ability of the borrower to repay their obligations as agreed. Commercial loans are primarily made based on the identified cash flows of the borrower and, secondarily, on the underlying collateral provided by the borrower. Most commercial loans are secured by the assets being financed or other business assets, such as accounts receivable or inventory, and include personal guarantees.
	Agricultural loans are subject to underwriting standards and processes similar to commercial loans. These agricultural loans are based primarily on the identified cash flows of the borrower and secondarily on the underlying collateral provided by the borrower. Most agricultural loans are secured by the agriculture related assets being financed, such as farm, land, cattle or equipment, and include personal guarantees.
	Real estate loans are also subject to underwriting standards and processes similar to commercial and agricultural loans. These loans are underwritten primarily based on projected cash flows and, secondarily, as loans secured by real estate. The repayment of real estate loans is generally largely dependent on the successful operation of the property securing the loans or the business conducted on the property securing the loan. Real estate loans may be more adversely affected by conditions in the real estate markets or in the general economy. The properties securing the Company’s real estate portfolio are generally diverse in terms of type and geographic location within Texas. This diversity helps reduce the exposure to adverse economic events that affect any single market or industry. Generally, real estate loans are owner occupied which further reduces the Company’s risk.
	Consumer loan underwriting utilizes methodical credit standards and analysis to supplement the Company’s underwriting policies and procedures. The Company’s loan policy addresses types of consumer loans that may be originated and the collateral, if secured, which must be perfected. The relatively smaller individual dollar amounts of consumer loans that are spread over numerous individual borrowers also minimize the Company’s risk.
	The allowance for loan losses is an amount management believes is appropriate to absorb probable losses that have been incurred on existing loans as of the balance sheet date based upon management’s review and evaluation of the loan portfolio. The allowance for loan losses is comprised of three elements: (i) specific reserves determined based on probable losses on specific classified loans; (ii) a general reserve that considers historical loss rates; and (iii) qualitative reserves based upon general economic conditions and other qualitative risk factors both internal and external to the Company. The allowance for loan losses is increased by charges to income and decreased by charge-offs (net of recoveries). Management’s periodic evaluation of the appropriateness of the allowance is based on general economic conditions, the financial condition of borrowers, the value and liquidity of collateral, delinquency, prior loan loss experience, and the results of periodic reviews of the portfolio. For purposes of determining our general reserve, the loan portfolio, less cash secured loans, government guaranteed loans and classified loans, is multiplied by the Company’s historical loss rate. Specific allocations are increased in accordance with deterioration in credit quality and a corresponding increase in risk of loss on a particular loan. In addition, we adjust our allowance for qualitative factors such as current local economic conditions and trends, including, without limitations, unemployment, drought conditions, changes in lending staff, policies and procedures, changes in credit concentrations, changes in the trends and severity of problem loans and changes in trends in volume and terms of loans. This qualitative reserve serves to estimate for additional areas of incurred losses in our portfolio that are not reflected in our historic loss factors.
	Although we believe we use the best information available to make loan loss allowance determinations, future adjustments could be necessary if circumstances or economic conditions differ substantially from the assumptions used in making our initial determinations. A further downturn in the economy and employment could result in increased levels of non-performing assets and charge-offs, increased loan provisions and reductions in income. Additionally, bank regulatory agencies periodically review our allowance for loan losses and methodology and could require, in accordance with generally accepted accounting principles, additional provisions to the allowance for loan losses is based on their judgment of information available to them at the time of their examination as well as changes to our methodology.
	Accrual of interest is discontinued on a loan and payments are applied to principal when management believes, after considering economic and business conditions and collection efforts, the borrower’s financial condition is such that collection of interest is doubtful. Except consumer loans, generally all loans past due greater than 90 days, based on contractual terms, are placed on non-accrual. Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured. Consumer loans are generally charged-off when a loan becomes past due 90 days. For other loans in the portfolio, facts and circumstances are evaluated in making charge-off decisions.
	Loans are considered impaired when, based on current information and events, management determines that it is probable we will be unable to collect all amounts due in accordance with the loan agreement, including scheduled principal and interest payments. If a loan is impaired, a specific valuation allowance is allocated, if necessary. Interest payments on impaired loans are typically applied to principal unless collectability of the principal amount is reasonably assured, in which case interest is recognized on a cash basis. Impaired loans, or portions thereof, are charged off when deemed uncollectable.
	The Company’s policy requires measurement of the allowance for an impaired, collateral dependent loan based on the fair value of the collateral. Other loan impairments are measured based on the present value of expected future cash flows or the loan’s observable market price. At September 30, 2014 and 2013, and December 31, 2013, all significant impaired loans have been determined to be collateral dependent and the allowance for loss has been measured utilizing the estimated fair value of the collateral.
	From time to time, the Company modifies its loan agreement with a borrower. A modified loan is considered a troubled debt restructuring when two conditions are met: (i) the borrower is experiencing financial difficulty and (ii) concessions are made by the Company that would not otherwise be considered for a borrower with similar credit risk characteristics. Modifications to loan terms may include a lower interest rate, a reduction of principal, or a longer term to maturity. For all impaired loans, including the Company’s troubled debt restructurings, the Company performs a periodic, well-documented credit evaluation of the borrower’s financial condition and prospects for repayment to assess the likelihood that all principal and interest payments required under the terms of the agreement will be collected in full. When doubt exists about the ultimate collectability of principal and interest, the troubled debt restructuring remains on non-accrual status and payments received are applied to reduce principal to the extent necessary to eliminate such doubt. This determination of accrual status is judgmental and is based on facts and circumstances related to each troubled debt restructuring. To date, all of the troubled debt restructurings have been such that, after considering economic and business conditions and collection efforts, the collection of interest is doubtful and therefore remain on non-accrual. Each of these loans is individually evaluated for impairment and a specific reserve is recorded based on probable losses, taking into consideration the related collateral, modified loan terms and cash flow. As of September 30, 2014 and 2013, and December 31, 2013, all of the Company’s troubled debt restructured loans are included in the non-accrual totals.
	The Company originates certain mortgage loans for sale in the secondary market. Accordingly, these loans are classified as held for sale and are carried at the lower of cost or fair value on an aggregate basis. The mortgage loan sales contracts contain indemnification clauses should the loans default, generally in the first three to six months, or if documentation is determined not to be in compliance with regulations. The Company’s historic losses as a result of these indemnities have been insignificant.
	Loans acquired, including loans acquired in a business combination, are initially recorded at fair value with no valuation allowance. Acquired loans are segregated between those considered to be credit impaired and those deemed performing. To make this determination, management considers such factors as past due status, non-accrual status and credit risk ratings. The fair value of acquired performing loans is determined by discounting expected cash flows, both principal and interest, at prevailing market interest rates. The difference between the fair value and principal balances at acquisition date, the fair value discount, is accreted into interest income over the estimated life of each loan.
	Purchased credit impaired loans are those loans that showed evidence of deterioration of credit quality since origination and for which it is probable, at acquisition, that the Company will be unable to collect all amounts contractually owed. Their acquisition fair value was based on the estimate of cash flows, both principal and interest, expected to be collected or estimated collateral values if cash flows are not estimable, discounted at prevailing market rates of interest. The difference between the cash flows expected at acquisition and the investment in the loan, is recognized as interest income on a level-yield method over the life of the loan, unless management was unable to reasonably forecast cash flows in which case the loans were placed on non-accrual. Contractually required payments for interest and principal that exceed the cash flows expected at acquisition are not recognized as a yield adjustment. Increases in expected cash flows subsequent to the initial investment are recognized prospectively through adjustment of the yield on the loan over its remaining life. Decreases in expected cash flows are recognized as impairment. Valuation allowances on these impaired loans reflect only losses incurred after the acquisition. The carrying amount of purchased credit impaired loans at September 30, 2014 and 2013, and December 31, 2013 was $2,383,000, $2,954,000 and $2,707,000, respectively, compared to a contractual balance of $3,525,000, $4,218,000 and $3,970,000, respectively. Other purchased credit impaired loan disclosures were omitted due to immateriality.
	Loans held-for-investment by class of financing receivables are as follows (in thousands):
			September 30,								December 31,
			2014				2013				2013
	Commercial		$	612,092			$	571,973			$	596,730
	Agricultural			86,718				66,758				75,928
	Real estate			1,774,639				1,640,308				1,678,514
	Consumer			354,981				330,046				333,113
	Total loans held-for-investment		$	2,828,430			$	2,609,085			$	2,684,285
	Loans held for sale totaled $11,266,000, $5,724,000 and $5,163,000 at September 30, 2014 and 2013, and December 31, 2013, respectively, which were recorded at cost as fair value exceeded cost.
	The Company’s non-accrual loans, loans still accruing and past due 90 days or more and restructured loans are as follows (in thousands):
			September 30,								December 31,
			2014				2013				2013
	Non-accrual loans*		$	22,093			$	22,809			$	27,926
	Loans still accruing and past due 90 days or more			263				54				133
	Troubled debt restructured loans**			—				—				—
	Total		$	22,356			$	22,863			$	28,059
	*	Includes $2,383,000, $2,954,000 and $2,707,000 of purchased credit impaired loans as of September 30, 2014 and 2013, and December 31, 2013, respectively.
	**	Troubled debt restructured loans of $10,114,000, $14,737,000 and $13,298,000, whose interest collection, after considering economic and business conditions and collection efforts, is doubtful are included in non-accrual loans at September 30, 2014 and 2013, and December 31, 2013, respectively. At this time, all of our restructured loans are included in non-accrual loans.
	The Company’s recorded investment in impaired loans and the related valuation allowance are as follows (in thousands):
	September 30, 2014								September 30, 2013								December 31, 2013
	Recorded				Valuation				Recorded				Valuation				Recorded				Valuation
	Investment				Allowance				Investment				Allowance				Investment				Allowance
		$22,093			$	4,634			$	22,809			$	4,605			$	27,926			$	5,338
	The average recorded investment in impaired loans for the three and nine months ended September 30, 2014, and the year ended December 31, 2013 was approximately $24,893,000, $26,524,000 and $31,293,000, respectively. The Company had $23,629,000, $28,535,000 and $31,128,000 in non-accrual, past due 90 days still accruing and restructured loans and foreclosed assets at September 30, 2014 and 2013, and December 31, 2013, respectively. Non-accrual loans at September 30, 2014 and 2013, and December 31, 2013, consisted of the following by class of financing receivables (in thousands):
			September 30,								December 31,
			2014				2013				2013
	Commercial		$	3,481			$	1,986			$	4,281
	Agricultural			102				97				131
	Real estate			17,712				20,036				22,548
	Consumer			798				690				966
	Total		$	22,093			$	22,809			$	27,926
	No significant additional funds are committed to be advanced in connection with impaired loans as of September 30, 2014.
	The Company’s impaired loans and related allowance as of September 30, 2014 and 2013, and December 31, 2013, are summarized in the following tables by class of financing receivables (in thousands). No interest income was recognized on impaired loans subsequent to their classification as impaired.
	September 30,		Unpaid				Recorded				Recorded				Total				Related				Year-to-Date		Three-month
	2014		Contractual				Investment				Investment				Recorded				Allowance				Average		Average
			Principal				With No				With				Investment								Recorded		Recorded
			Balance				Allowance*				Allowance												Investment		Investment
	Commercial		$	3,928			$	278			$	3,203			$	3,481			$	1,160			$	3,990	$	3,713
	Agricultural			113				—				102				102				37				113		104
	Real Estate			23,559				5,546				12,166				17,712				3,256				21,510		20,212
	Consumer			977				467				331				798				181				911		864
	Total		$	28,577			$	6,291			$	15,802			$	22,093			$	4,634			$	26,524	$	24,893
	*	Includes $2,383,000 of purchased credit impaired loans.
	September 30,		Unpaid				Recorded				Recorded				Total				Related				Year-to-Date		Three-month
	2013		Contractual				Investment				Investment				Recorded				Allowance				Average		Average
			Principal				With No				With				Investment								Recorded		Recorded
			Balance				Allowance*				Allowance												Investment		Investment
Commercial		$	2,545			$	701			$	1,285			$	1,986			$	710			$	1,779	$	2,113
Agricultural			105				91				6				97				6				104		99
Real Estate			25,085				4,290				15,746				20,036				3,628				19,985		20,757
Consumer			824				212				478				690				261				662		799
Total		$	28,559			$	5,294			$	17,515			$	22,809			$	4,605			$	22,530	$	23,768
*	Includes $2,954,000 of purchased credit impaired loans.
December 31,		Unpaid				Recorded				Recorded				Total				Related				Average
2013		Contractual				Investment With				Investment				Recorded				Allowance				Recorded
		Principal				No Allowance*				With				Investment								Investment
		Balance								Allowance
Commercial		$	4,764			$	934			$	3,348			$	4,282			$	1,079			$	5,017
Agricultural			139				17				114				131				41				144
Real Estate			31,704				5,794				16,753				22,547				4,006				25,060
Consumer			1,117				545				421				966				212				1,072
Total		$	37,724			$	7,290			$	20,636			$	27,926			$	5,338			$	31,293
*	Includes $2,707,000 of purchased credit impaired loans.
The Company recognized interest income on impaired loans prior to being classified as impaired of approximately $685,000 during the year ended December 31, 2013. Such amounts for the three-month and nine-month periods ended September 30, 2014 and 2013 were not significant.
From a credit risk standpoint, the Company rates its loans in one of four categories: (i) pass, (ii) special mention, (iii) substandard or (iv) doubtful. Loans rated as loss are charged-off.
The ratings of loans reflect a judgment about the risks of default and loss associated with the loan. The Company reviews the ratings on our credits as part of our on-going monitoring of the credit quality of our loan portfolio. Ratings are adjusted to reflect the degree of risk and loss that are felt to be inherent in each credit as of each reporting period. Our methodology is structured so that specific allocations are increased in accordance with deterioration in credit quality (and a corresponding increase in risk and loss) or decreased in accordance with improvement in credit quality (and a corresponding decrease in risk and loss).
Credits rated special mention show clear signs of financial weakness or deterioration in credit worthiness, however, such concerns are not so pronounced that the Company generally expects to experience significant loss within the short-term. Such credits typically maintain the ability to perform within standard credit terms and credit exposure is not as prominent as credits rated more harshly.
Credits rated substandard are those in which the normal repayment of principal and interest may be, or has been, jeopardized by reason of adverse trends or developments of a financial, managerial, economic or political nature, or important weaknesses exist in collateral. A protracted workout on these credits is a distinct possibility. Prompt corrective action is therefore required to strengthen the Company’s position, and/or to reduce exposure and to assure that adequate remedial measures are taken by the borrower. Credit exposure becomes more likely in such credits and a serious evaluation of the secondary support to the credit is performed.
Credits rated doubtful are those in which full collection of principal appears highly questionable, and which some degree of loss is anticipated, even though the ultimate amount of loss may not yet be certain and/or other factors exist which could affect collection of debt. Based upon available information, positive action by the Company is required to avert or minimize loss. Credits rated doubtful are generally also placed on non-accrual.
The following summarizes the Company’s internal ratings of its loans held-for-investment by class of financing receivables and portfolio segments, which are the same, at September 30, 2014 and December 31, 2013 (in thousands):
September 30,		Pass				Special				Substandard				Doubtful				Total
2014						Mention
Commercial		$	597,717			$	3,649			$	10,726			$	—			$	612,092
Agricultural			86,272				93				353				—				86,718
Real Estate			1,710,201				18,741				45,613				84				1,774,639
Consumer			352,850				601				1,527				3				354,981
Total		$	2,747,040			$	23,084			$	58,219			$	87			$	2,828,430
December 31,		Pass				Special				Substandard				Doubtful				Total
2013						Mention
Commercial		$	584,547			$	3,032			$	9,151			$	—			$	596,730
Agricultural			75,382				245				298				3				75,928
Real Estate			1,609,242				20,773				48,352				147				1,678,514
Consumer			330,870				639				1,595				9				333,113
Total		$	2,600,041			$	24,689			$	59,396			$	159			$	2,684,285
At September 30, 2014 and December 31, 2013, the Company’s past due loans are as follows (in thousands):
September 30,		15-59				60-89				Greater				Total Past				Current				Total Loans		90 Days
2014		Days				Days				Than 90				Due										Past Due
		Past				Past				Days														Still
		Due*				Due																		Accruing
Commercial		$	2,726			$	110			$	316			$	3,152			$	608,940			$	612,092	$	111
Agricultural			294				59				—				353				86,365				86,718		—
Real Estate			15,404				930				2,216				18,550				1,756,089				1,774,639		102
Consumer			1,742				292				297				2,331				352,650				354,981		50
Total		$	20,166			$	1,391			$	2,829			$	24,386			$	2,804,044			$	2,828,430	$	263
December 31,		15-59				60-89				Greater				Total Past				Current				Total Loans		90 Days
2013		Days				Days				Than 90				Due										Past Due
		Past				Past				Days														Still
		Due*				Due																		Accruing
Commercial		$	5,303			$	287			$	420			$	6,010			$	590,720			$	596,730	$	—
Agricultural			355				—				—				355				75,573				75,928		—
Real Estate			13,787				2,489				1,876				18,152				1,660,362				1,678,514		55
Consumer			2,708				582				277				3,567				329,546				333,113		78
Total		$	22,153			$	3,358			$	2,573			$	28,084			$	2,656,201			$	2,684,285	$	133
*	The Company monitors commercial, agricultural and real estate loans after such loans are 15 days past due. Consumer loans are monitored after such loans are 30 days past due.
The allowance for loan losses as of September 30, 2014 and 2013, and December 31, 2013, is presented below. Management has evaluated the appropriateness of the allowance for loan losses by estimating the probable losses in various categories of the loan portfolio, which are identified below (in thousands):
		September 30,								December 31,
		2014				2013				2013
Allowance for loan losses provided for:
Loans specifically evaluated as impaired		$	4,634			$	4,605			$	5,338
Remaining portfolio			31,754				30,195				28,562
Total allowance for loan losses		$	36,388			$	34,800			$	33,900
The following table details the allowance for loan losses at September 30, 2014 and December 31, 2013 by portfolio segment (in thousands). There were no allowances for purchased credit impaired loans at September 30, 2014 or December 31, 2013. Allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories.
September 30, 2014		Commercial				Agricultural				Real Estate				Consumer				Total
Loans individually evaluated for impairment		$	2,837			$	127			$	7,081			$	388			$	10,433
Loans collectively evaluated for impairment			4,649				258				19,218				1,830				25,955
Total		$	7,486			$	385			$	26,299			$	2,218			$	36,388
December 31, 2013		Commercial				Agricultural				Real Estate				Consumer				Total
Loans individually evaluated for impairment		$	2,755			$	125			$	7,215			$	378			$	10,473
Loans collectively evaluated for impairment			3,685				258				17,725				1,759				23,427
Total		$	6,440			$	383			$	24,940			$	2,137			$	33,900
Changes in the allowance for loan losses for the three and nine months ended September 30, 2014 and 2013 are summarized as follows by portfolio segment (in thousands):
Three months ended		Commercial				Agricultural				Real Estate				Consumer				Total
September 30, 2014
Beginning balance		$	6,861			$	364			$	26,561			$	2,106			$	35,892
Provision for loan losses			635				7				(80	)			334				896
Recoveries			72				14				42				86				214
Charge-offs			(82	)			—				(224	)			(308	)			(614	)
Ending balance		$	7,486			$	385			$	26,299			$	2,218			$	36,388
Three months ended		Commercial				Agricultural				Real Estate				Consumer				Total
September 30, 2013
Beginning balance		$	6,736			$	1,493			$	23,902			$	1,968			$	34,099
Provision for loan losses			354				(999	)			1,644				350				1,349
Recoveries			141				10				42				104				297
Charge-offs			(218	)			(86	)			(294	)			(347	)			(945	)
Ending balance		$	7,013			$	418			$	25,294			$	2,075			$	34,800
Nine months ended		Commercial				Agricultural				Real Estate				Consumer				Total
September 30, 2014
Beginning balance		$	6,440			$	383			$	24,940			$	2,137			$	33,900
Provision for loan losses			1,189				(14	)			1,988				547				3,710
Recoveries			225				17				361				386				989
Charge-offs			(368	)			(1	)			(990	)			(852	)			(2,211	)
Ending balance		$	7,486			$	385			$	26,299			$	2,218			$	36,388
Nine months ended		Commercial				Agricultural				Real Estate				Consumer				Total
September 30, 2013
Beginning balance		$	7,343			$	1,541			$	24,063			$	1,892			$	34,839
Provision for loan losses			(77	)			(1,056	)			3,035				680				2,582
Recoveries			329				29				95				266				719
Charge-offs			(582	)			(96	)			(1,899	)			(763	)			(3,340	)
Ending balance		$	7,013			$	418			$	25,294			$	2,075			$	34,800
The Company’s recorded investment in loans as of September 30, 2014 and December 31, 2013 related to the balance in the allowance for loan losses on the basis of the Company’s impairment methodology was as follows (in thousands). Purchased credit impaired loans of $2,383,000 and $2,707,000 at September 30, 2014 and December 31, 2013, respectively, are included in loans individually evaluated for impairment.
September 30, 2014		Commercial				Agricultural				Real Estate				Consumer				Total
Loans individually evaluated for impairment		$	14,375			$	446			$	64,438			$	2,131			$	81,390
Loans collectively evaluated for impairment			597,717				86,272				1,710,201				352,850				2,747,040
Total		$	612,092			$	86,718			$	1,774,639			$	354,981			$	2,828,430
December 31, 2013		Commercial				Agricultural				Real Estate				Consumer				Total
Loans individually evaluated for impairment		$	12,183			$	546			$	69,272			$	2,243			$	84,244
Loans collectively evaluated for impairment			584,547				75,382				1,609,242				330,870				2,600,041
Total		$	596,730			$	75,928			$	1,678,514			$	333,113			$	2,684,285
The Company’s loans that were modified in the three and nine months ended September 30, 2014 and 2013 and considered troubled debt restructurings are as follows (in thousands):
		Three Months Ended September 30, 2014												Nine Months Ended September 30, 2014
						Pre-Modification				Post-Modification								Pre-Modification				Post-Modification
						Recorded				Recorded								Recorded				Recorded
		Number				Investment				Investment				Number				Investment				Investment
Commercial			1			$	158			$	158				6			$	557			$	557
Agricultural			—				—				—				1				39				39
Real Estate			1				40				40				5				630				630
Consumer			—				—				—				3				11				11
Total			2			$	198			$	198				15			$	1,237			$	1,237
		Three Months Ended September 30, 2013												Nine Months Ended September 30, 2013
						Pre-Modification				Post-Modification								Pre-Modification				Post-Modification
						Recorded				Recorded								Recorded				Recorded
		Number				Investment				Investment				Number				Investment				Investment
Commercial			—			$	—			$	—				3			$	218			$	218
Agricultural			—				—				—				1				24				24
Real Estate			—				—				—				8				3,779				3,779
Consumer			4				86				86				5				123				123
Total			4			$	86			$	86				17			$	4,144			$	4,144
The balances below provide information as to how the loans were modified as troubled debt restructured loans during the three and nine months ended September 30, 2014 and 2013 (in thousands):
		Three Months Ended September 30, 2014												Nine Months Ended September 30, 2014
		Adjusted				Extended				Combined				Adjusted				Extended				Combined
		Interest				Maturity				Rate and				Interest				Maturity				Rate and
		Rate								Maturity				Rate								Maturity
Commercial		$	—			$	158			$	—			$	—			$	255			$	302
Agricultural			—				—				—				—				—				39
Real Estate			—				—				40				—				118				512
Consumer			—				—				—				—				8				3
Total		$	—			$	158			$	40			$	—			$	381			$	856
		Three Months Ended September 30, 2013												Nine Months Ended September 30, 2013
		Adjusted				Extended				Combined				Adjusted				Extended				Combined
		Interest				Maturity				Rate and				Interest				Maturity				Rate and
		Rate								Maturity				Rate								Maturity
Commercial		$	—			$	—			$	—			$	—			$	218			$	—
Agricultural			—				—				—				—				24				—
Real Estate			—				—				—				420				350				3,009
Consumer			—				82				4				—				119				4
Total		$	—			$	82			$	4			$	420			$	711			$	3,013
Certain loans were modified as troubled debt restructured loans within the previous 12 months and for which there was a payment default. A default for purposes of this disclosure is a troubled debt restructured loan in which the borrower is 90 days past due or more or results in the foreclosure and repossession of the applicable collateral. The loans with payment default are as follows (dollars in thousands):
		Three Months Ended September 30,								Nine Months Ended September 30,
		2014								2014
		Number				Balance				Number				Balance
Commercial			—			$	—				—			$	—
Agriculture			—				—				—				—
Real Estate			—				—				—				—
Consumer			—				—				1				32
Total			—			$	—				1			$	32
		Three Months Ended September 30,								Nine Months Ended September 30,
		2013								2013
		Number				Balance				Number				Balance
Commercial			1			$	71				6			$	316
Agriculture			—				—				—				—
Real Estate			—				—				—				—
Consumer			—				—				—				—
Total			1			$	71				6			$	316
As of September 30, 2014, the Company has no commitments to lend additional funds to loan customers whose terms have been modified in troubled debt restructurings.
Our subsidiary bank has established a line of credit with the Federal Home Loan Bank of Dallas to provide liquidity and meet pledging requirements for those customers eligible to have securities pledged to secure certain uninsured deposits. At September 30, 2014, $1,634,405,000 in loans held by our bank subsidiary were subject to blanket liens as security for this line of credit. At September 30, 2014, $1,038,000 in advances were outstanding and $7,000,000 in letters of credit were outstanding under this line of credit. The letters of credit were pledged as collateral for public funds held by our bank subsidiary.

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Note 6 - Income Taxes
	Income tax expense was $7,843,000 for the third quarter of 2014 as compared to $6,121,000 for the same period in 2013. The Company’s effective tax rates on pretax income were 25.08% and 23.83% for the third quarter of 2014 and 2013, respectively. Income tax expense was $21,705,000 for nine months ended September 30, 2014 as compared to $18,723,000 for same period in 2013. The Company’s effective tax rate on pretax income was 24.48% and 24.52% for the nine months ended September 30, 2014 and 2013, respectively. The effective tax rates differ from the statutory federal tax rate of 35% primarily due to tax exempt interest income earned on certain investment securities and loans, the deductibility of dividends paid to our employee stock ownership plan and the settlement of a bank owned life insurance contract.

Stock_Based_Compensation

Stock Based Compensation	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Stock Based Compensation	'
	Note 7 - Stock Based Compensation
	The Company grants incentive stock options for a fixed number of shares with an exercise price equal to the fair value of the shares at the date of grant to employees. At September 30, 2014, no options have been granted in 2014. On October 22, 2013, the Company granted 395,000 shares in incentive stock options at an exercise price of $30.85 to its employees. The Company recorded stock option expense totaling $174,000 and $88,000 for the three months ended September 30, 2014 and 2013, respectively. The Company recorded stock option expense totaling $532,000 and $264,000 for the nine-month periods ended September 30, 2014 and 2013, respectively. The additional disclosure requirements under authoritative accounting guidance have been omitted due to immateriality.

Pension_Plan

Pension Plan	9 Months Ended
	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Pension Plan	'
	Note 8 - Pension Plan
	The Company’s defined benefit pension plan was frozen effective January 1, 2004, whereby no new participants will be added to the plan and no additional years of service will accrue to participants, unless the pension plan is reinstated at a future date. The pension plan covered substantially all of the Company’s employees at the time. The benefits for each employee were based on years of service and a percentage of the employee’s qualifying compensation during the final years of employment. The Company’s funding policy was and is to contribute annually the amount necessary to satisfy the Internal Revenue Service’s funding standards. Contributions to the pension plan, prior to freezing the plan, were intended to provide not only for benefits attributed to service to date but also for those expected to be earned in the future. As a result of the Pension Protection Act of 2006 (the “Protection Act”), the Company will be required to contribute amounts in future years to fund any shortfalls. The Company has evaluated the provisions of the Protection Act as well as the Internal Revenue Service’s funding standards to develop a plan for funding in future years. The Company made a contribution totaling $1,000,000 in 2013 and has to date made no contributions in 2014.
	In October 2014, the Company approved a plan to offer plan participants that are no longer employed by the Company the option to receive a one-time lump sum payment in lieu of future benefits to be received under the plan. The lump sum payment offered approximates the respective participant’s pension benefit obligation and is not expected to have a significant impact on the Company’s financial statements.
	Net periodic benefit costs totaling $107,000 and $208,000 were recorded for the three months ended September 30, 2014 and 2013, respectively. Net periodic benefit costs totaling $321,000 and $623,000 were recorded for the nine months ended September 30, 2014 and 2013, respectively.

Fair_Value_Disclosures

Fair Value Disclosures	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Disclosures	'
	Note 9 - Fair Value Disclosures
	The authoritative accounting guidance for fair value measurements defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. A fair value measurement assumes that the transaction to sell the asset or transfer the liability occurs in the principal market for the asset or liability or, in the absence of a principal market, the most advantageous market for the asset or liability. The price in the principal (or most advantageous) market used to measure the fair value of the asset or liability shall not be adjusted for transaction costs. An orderly transaction is a transaction that assumes exposure to the market for a period prior to the measurement date to allow for marketing activities that are usual and customary for transactions involving such assets and liabilities; it is not a forced transaction. Market participants are buyers and sellers in the principal market that are (i) independent, (ii) knowledgeable, (iii) able to transact, and (iv) willing to transact.
	The authoritative accounting guidance requires the use of valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets and liabilities. The income approach uses valuation techniques to convert future amounts, such as cash flows or earnings, to a single present amount on a discounted basis. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset (replacement costs). Valuation techniques should be consistently applied. Inputs to valuation techniques refer to the assumptions that market participants would use in pricing the asset or liability. Inputs may be observable, meaning those that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from independent sources, or unobservable, meaning those that reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. In that regard,
	the authoritative guidance establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows:
		•		Level 1 Inputs – Unadjusted quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date.
		•		Level 2 Inputs – Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (for example, interest rates, volatilities, prepayment speeds, loss severities, credit risks and default rates) or inputs that are derived principally from or corroborated by observable market data by correlation or other means.
		•		Level 3 Inputs – Significant unobservable inputs that reflect an entity’s own assumptions that market participants would use in pricing the assets or liabilities.
	A description of the valuation methodologies used for assets and liabilities measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below.
	In general, fair value is based upon quoted market prices, where available. If such quoted market prices are not available, fair value is based upon internally developed models that primarily use, as inputs, observable market-based parameters. Valuation adjustments may be made to ensure that financial instruments are recorded at fair value. While management believes the Company’s valuation methodologies are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date.
	Securities classified as available-for-sale and trading are reported at fair value utilizing Level 1 and Level 2 inputs. For these securities, the Company obtains fair value measurements from an independent pricing service. The fair value measurements consider observable data that may include market spreads, cash flows, the United States Treasury yield curve, live trading levels, trade execution data, dealer quotes, market consensus prepayments speeds, credit information and the security’s terms and conditions, among other items. Securities are considered to be measured with Level 1 inputs at the time of purchase and for 30 days following. After 30 days, the majority of securities are transferred to Level 2 as they are considered to be measured with Level 2 inputs, with the exception of U. S. Treasury securities and any other security for which there remain Level 1 inputs. Transfers are recognized on the actual date of transfer.
	There were no transfers between Level 2 and Level 3 during the three and nine months ended September 30, 2014 or 2013.
	The following table summarizes financial assets and financial liabilities measured at fair value on a recurring basis as of September 30, 2014, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value (dollars in thousands):
			Level 1			Level 2			Level 3		Total Fair
			Inputs			Inputs			Inputs		Value
	Available-for-sale investment securities:
	U.S. Treasury securities		$	520		$	—		$	—	$	520
	Obligations of U. S. government sponsored-enterprises and agencies			—			107,301			—		107,301
	Obligations of states and political subdivisions			18,546			1,083,423			—		1,101,969
	Corporate bonds			—			95,038			—		95,038
	Residential mortgage-backed securities			45,769			766,098			—		811,867
	Commercial mortgage-backed securities			—			132,412			—		132,412
	Other securities			4,655			—			—		4,655
	Total		$	69,490		$	2,184,272		$	—	$	2,253,762
	Certain financial assets and financial liabilities are measured at fair value on a nonrecurring basis, that is, the instruments are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). Financial assets and financial liabilities measured at fair value on a non-recurring basis include the following at September 30, 2014:
	Impaired Loans – Impaired loans are reported at the fair value of the underlying collateral if repayment is expected solely from the collateral. Collateral values are estimated using Level 2 inputs based on observable market data, or Level 3 inputs based on the discounting of the collateral. At September 30, 2014, impaired loans with a carrying value of $22,093,000 were reduced by specific valuation reserves totaling $4,634,000 resulting in a net fair value of $17,459,000.
	Loans Held for Sale – Loans held for sale are reported at the lower of cost or fair value. In determining whether the fair value of loans held for sale is less than cost when quoted market prices are not available, the Company considers investor commitments/contracts. These loans are considered Level 2 of the fair value hierarchy. At September 30, 2014, the Company’s mortgage loans held for sale were recorded at cost as fair value exceeded cost.
	Certain non-financial assets and non-financial liabilities measured at fair value on a non-recurring basis include other real estate owned, goodwill and other intangible assets and other non-financial long-lived assets. Non-financial assets measured at fair value on a non-recurring basis during the three and nine months ended September 30, 2014 and 2013 include other real estate owned which, subsequent to their initial transfer to other real estate owned from loans, were re-measured at fair value through a write-down included in gain (loss) on sale of foreclosed assets. During the reported periods, all fair value measurements for foreclosed assets utilized Level 2 inputs based on observable market data, generally third-party appraisals, or Level 3 inputs based on customized discounting criteria. These appraisals are evaluated individually and discounted as necessary due to the age of the appraisal, lack of comparable sales, expected holding periods of property or special use type of the property. Such discounts vary by appraisal based on the above factors but generally range from 5% to 25% of the appraised value. Reevaluation of other real estate owned is performed at least annually as required by regulatory guidelines or more often if particular circumstances arise. The following table presents other real estate owned that were re-measured subsequent to their initial transfer to other real estate owned (dollars in thousands):
			Three Months Ended
			September 30,
			2014			2013
	Carrying value of other real estate owned prior to re-measurement		$	173		$	238
	Write-downs included in gain (loss) on sale of other real estate owned			(46	)		(65	)
	Fair value		$	127		$	173
			Nine Months Ended
			September 30,
			2014			2013
	Carrying value of other real estate owned prior to re-measurement		$	881		$	2,065
	Write-downs included in gain (loss) on sale of other real estate owned			(135	)		(369	)
	Fair value		$	746		$	1,696
	At September 30, 2014 and 2013, and December 31, 2013, other real estate owned totaled $1,185,000, $5,490,000 and $2,903,000, respectively.
	The Company is required under current authoritative accounting guidance to disclose the estimated fair value of their financial instrument assets and liabilities including those subject to the requirements discussed above. For the Company, as for most financial institutions, substantially all of its assets and liabilities are considered financial instruments. Many of the Company’s financial instruments, however, lack an available trading market as characterized by a willing buyer and willing seller engaging in an exchange transaction.
	The estimated fair value amounts of financial instruments have been determined by the Company using available market information and appropriate valuation methodologies. However, considerable judgment is required to interpret data to develop the estimates of fair value. Accordingly, the estimates presented herein are not necessarily indicative of the amounts the Company could realize in a current market exchange. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts.
	In addition, reasonable comparability between financial institutions may not be likely due to the wide range of permitted valuation techniques and numerous estimates that must be made given the absence of active secondary markets for many of the financial instruments. This lack of uniform valuation methodologies also introduces a greater degree of subjectivity to these estimated fair values.
	Cash and due from banks, federal funds sold, interest-bearing deposits and time deposits in banks and accrued interest receivable and payable are liquid in nature and considered Levels 1 or 2 of the fair value hierarchy.
	Financial instruments with stated maturities have been valued using a present value discounted cash flow with a discount rate approximating current market for similar assets and liabilities and are considered Levels 2 and 3 of the fair value hierarchy. Financial instrument liabilities with no stated maturities have an estimated fair value equal to both the amount payable on demand and the carrying value and are considered Level 1 of the fair value hierarchy.
	The carrying value and the estimated fair value of the Company’s contractual off-balance-sheet unfunded lines of credit, loan commitments and letters of credit, which are generally priced at market at the time of funding, are not material.
	The estimated fair values and carrying values of all financial instruments under current authoritative guidance at September 30, 2014 and December 31, 2013, were as follows (in thousands):
			September 30,						December 31,
			2014						2013
			Carrying			Estimated			Carrying		Estimated		Fair Value
			Value			Fair Value			Value		Fair Value		Hierarchy
	Cash and due from banks		$	149,957		$	149,957		$	183,084	$	183,084	Level 1
	Federal funds sold			4,785			4,785			3,430		3,430	Level 1
	Interest-bearing deposits in banks			83,994			83,994			25,498		25,498	Level 1
	Interest-bearing time deposits in banks			19,234			19,285			31,917		32,059	Level 2
	Available-for-sale securities			2,253,762			2,253,762			2,057,723		2,057,723	Levels 1 and 2
	Held-to-maturity securities			554			560			684		694	Level 2
	Loans			2,803,308			2,815,509			2,655,548		2,667,743	Level 3
	Accrued interest receivable			23,420			23,420			26,865		26,865	Level 2
	Deposits with stated maturities			664,221			666,123			686,627		688,876	Level 2
	Deposits with no stated maturities			3,800,143			3,800,143			3,448,448		3,448,448	Level 1
	Short term borrowings			341,909			341,909			463,888		463,888	Level 2
	Accrued interest payable			275			275			299		299	Level 2

Recently_Issued_Authoritative_

Recently Issued Authoritative Accounting Guidance	9 Months Ended
	Sep. 30, 2014
Accounting Changes and Error Corrections [Abstract]	'
Recently Issued Authoritative Accounting Guidance	'
	Note 10 - Recently Issued Authoritative Accounting Guidance
	In 2014, the Financial Accounting Standards Board (the “FASB”) amended its authoritative guidance related to residential real estate to clarify that an in substance repossession or foreclosure occurs, and 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 new guidance is effective for the Company on January 1, 2015 and is not expected to have a significant impact to the Company’s financial statements.
	In 2014, the FASB issued a comprehensive new revenue recognition standard that will supersede substantially all existing revenue recognition guidance. The new standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. In doing so, companies will need to use more judgment and make more estimates than under existing guidance. These may include identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. The new standard will be effective in the first quarter of 2017 and is not expected to have a significant impact to the Company’s financial statements.
	In 2014, the FASB amended its authoritative guidance related to repurchase-to-maturity transaction to require that repurchase-to-maturity transactions be accounted for as secured borrowings consistent with the accounting for other repurchase agreements. In addition, the amendment requires separate accounting for repurchase financings, which entails the transfer of a financial asset executed contemporaneously with a repurchase agreement with the same counterparty. The amendment requires entities to disclose certain information about transfers accounted for as sales in transactions that economically similar to repurchase agreements. In addition, the amendment requires disclosures related to collateral, remaining contractual tenor and of the potential risks associated with repurchase agreements, securities lending transactions and repurchase-to-maturity transactions. The amendment will be effective on January 1, 2015 and is not expected to have a significant impact on the Company’s financial statements.

Interestbearing_Time_Deposits_1

Interest-bearing Time Deposits in Banks and Securities (Tables)	9 Months Ended
	Sep. 30, 2014
Cash and Cash Equivalents [Abstract]	'
Summary of Available-for-Sale Securities	'
	A summary of the Company’s available-for-sale securities follows (in thousands):
		September 30, 2014
		Amortized		Gross		Gross			Estimated
		Cost Basis		Unrealized		Unrealized			Fair Value
				Holding Gains		Holding Losses
	U.S. Treasury securities	$	520	$	—	$	—		$	520
	Obligations of U.S. government sponsored enterprises and agencies		106,339		964		(2	)		107,301
	Obligations of states and political subdivisions		1,046,148		56,398		(577	)		1,101,969
	Corporate bonds and other		96,424		3,269		—			99,693
	Residential mortgage-backed securities		803,072		14,395		(5,600	)		811,867
	Commercial mortgage-backed securities		134,769		31		(2,388	)		132,412
	Total securities available-for-sale	$	2,187,272	$	75,057	$	(8,567	)	$	2,253,762
		31-Dec-13
		Amortized		Gross		Gross			Estimated
		Cost Basis		Unrealized		Unrealized			Fair Value
				Holding Gains		Holding Losses
	Obligations of U.S. government sponsored-enterprises and agencies	$	136,416	$	1,672	$	—		$	138,088
	Obligations of states and political subdivisions		974,608		27,980		(11,319	)		991,269
	Corporate bonds and other		105,490		3,550		—			109,040
	Residential mortgage-backed securities		706,289		12,253		(7,922	)		710,620
	Commercial mortgage-backed securities		112,323		—		(3,617	)		108,706
	Total securities available-for-sale	$	2,035,126	$	45,455	$	(22,858	)	$	2,057,723
Amortized Cost and Estimated Fair Value of Available-for-Sale Securities	'
	The amortized cost and estimated fair value of available-for-sale securities at September 30, 2014, by contractual or expected maturity, as applicable, are shown below (in thousands):
		Amortized		Estimated
		Cost Basis		Fair Value
	Due within one year	$	76,858	$	77,722
	Due after one year through five years		663,151		695,484
	Due after five years through ten years		502,028		527,658
	Due after ten years		7,394		8,619
	Mortgage-backed securities		937,841		944,279
	Total	$	2,187,272	$	2,253,762
Continuous Unrealized-Loss Position of Available-for-Sale and Held-to-Maturity Securities	'
	The following tables disclose, as of September 30, 2014 and December 31, 2013, the Company’s investment securities that have been in a continuous unrealized-loss position for less than 12 months and for 12 months or longer (in thousands):
		Less than 12 Months				12 Months or Longer					Total
	September 30, 2014	Fair Value		Unrealized		Fair Value			Unrealized		Fair Value		Unrealized
				Loss					Loss				Loss
	Obligations of U.S. Government sponsored enterprises and Agencies	$	876	$	2	$	—		$	—	$	876	$	2
	Obligations of states and political subdivisions		17,871		38		50,158			539		68,029		577
	Residential mortgage-backed securities		82,382		450		134,271			5,150		216,653		5,600
	Commercial mortgage-backed securities		6,435		15		102,353			2,373		108,788		2,388
	Total	$	107,564	$	505	$	286,782		$	8,062	$	394,346	$	8,567
		Less than 12 Months				12 Months or Longer					Total
	December 31, 2013	Fair Value		Unrealized		Fair			Unrealized		Fair Value		Unrealized
				Loss		Value			Loss				Loss
	Obligations of states and political subdivisions	$	316,394	$	10,973	$	4,153		$	346	$	320,547	$	11,319
	Residential mortgage-backed securities		228,423		7,623		5,624			299		234,047		7,922
	Commercial mortgage-backed securities		108,706		3,617		—			—		108,706		3,617
	Total	$	653,523	$	22,213	$	9,777		$	645	$	663,300	$	22,858

Loans_and_Allowance_for_Loan_L1

Loans and Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2014
Receivables [Abstract]	'
Loans Held-for-Investment by Class of Financing Receivables	'
	Loans held-for-investment by class of financing receivables are as follows (in thousands):
			September 30,								December 31,
			2014				2013				2013
	Commercial		$	612,092			$	571,973			$	596,730
	Agricultural			86,718				66,758				75,928
	Real estate			1,774,639				1,640,308				1,678,514
	Consumer			354,981				330,046				333,113
	Total loans held-for-investment		$	2,828,430			$	2,609,085			$	2,684,285
Non-Accrual Loans, Loans Still Accruing and Past Due 90 Days or More and Restructured Loans	'
	The Company’s non-accrual loans, loans still accruing and past due 90 days or more and restructured loans are as follows (in thousands):
			September 30,								December 31,
			2014				2013				2013
	Non-accrual loans*		$	22,093			$	22,809			$	27,926
	Loans still accruing and past due 90 days or more			263				54				133
	Troubled debt restructured loans**			—				—				—
	Total		$	22,356			$	22,863			$	28,059
	*	Includes $2,383,000, $2,954,000 and $2,707,000 of purchased credit impaired loans as of September 30, 2014 and 2013, and December 31, 2013, respectively.
	**	Troubled debt restructured loans of $10,114,000, $14,737,000 and $13,298,000, whose interest collection, after considering economic and business conditions and collection efforts, is doubtful are included in non-accrual loans at September 30, 2014 and 2013, and December 31, 2013, respectively. At this time, all of our restructured loans are included in non-accrual loans.
Recorded Investment in Impaired Loans and Related Valuation Allowance	'
	The Company’s recorded investment in impaired loans and the related valuation allowance are as follows (in thousands):
	September 30, 2014								September 30, 2013								December 31, 2013
	Recorded				Valuation				Recorded				Valuation				Recorded				Valuation
	Investment				Allowance				Investment				Allowance				Investment				Allowance
		$22,093			$	4,634			$	22,809			$	4,605			$	27,926			$	5,338
Schedule of Non-Accrual Loans	'
	Non-accrual loans at September 30, 2014 and 2013, and December 31, 2013, consisted of the following by class of financing receivables (in thousands):
			September 30,								December 31,
			2014				2013				2013
	Commercial		$	3,481			$	1,986			$	4,281
	Agricultural			102				97				131
	Real estate			17,712				20,036				22,548
	Consumer			798				690				966
	Total		$	22,093			$	22,809			$	27,926
Schedule of Impaired Loans and Related Allowance	'
	The Company’s impaired loans and related allowance as of September 30, 2014 and 2013, and December 31, 2013, are summarized in the following tables by class of financing receivables (in thousands). No interest income was recognized on impaired loans subsequent to their classification as impaired.
	September 30,		Unpaid				Recorded				Recorded				Total				Related				Year-to-Date		Three-month
	2014		Contractual				Investment				Investment				Recorded				Allowance				Average		Average
			Principal				With No				With				Investment								Recorded		Recorded
			Balance				Allowance*				Allowance												Investment		Investment
	Commercial		$	3,928			$	278			$	3,203			$	3,481			$	1,160			$	3,990	$	3,713
	Agricultural			113				—				102				102				37				113		104
	Real Estate			23,559				5,546				12,166				17,712				3,256				21,510		20,212
	Consumer			977				467				331				798				181				911		864
	Total		$	28,577			$	6,291			$	15,802			$	22,093			$	4,634			$	26,524	$	24,893
	*	Includes $2,383,000 of purchased credit impaired loans.
	September 30,		Unpaid				Recorded				Recorded				Total				Related				Year-to-Date		Three-month
	2013		Contractual				Investment				Investment				Recorded				Allowance				Average		Average
			Principal				With No				With				Investment								Recorded		Recorded
			Balance				Allowance*				Allowance												Investment		Investment
	Commercial		$	2,545			$	701			$	1,285			$	1,986			$	710			$	1,779	$	2,113
	Agricultural			105				91				6				97				6				104		99
	Real Estate			25,085				4,290				15,746				20,036				3,628				19,985		20,757
	Consumer			824				212				478				690				261				662		799
	Total		$	28,559			$	5,294			$	17,515			$	22,809			$	4,605			$	22,530	$	23,768
	*	Includes $2,954,000 of purchased credit impaired loans.
	December 31,		Unpaid				Recorded				Recorded				Total				Related				Average
	2013		Contractual				Investment With				Investment				Recorded				Allowance				Recorded
			Principal				No Allowance*				With				Investment								Investment
			Balance								Allowance
	Commercial		$	4,764			$	934			$	3,348			$	4,282			$	1,079			$	5,017
	Agricultural			139				17				114				131				41				144
	Real Estate			31,704				5,794				16,753				22,547				4,006				25,060
	Consumer			1,117				545				421				966				212				1,072
	Total		$	37,724			$	7,290			$	20,636			$	27,926			$	5,338			$	31,293
	*	Includes $2,707,000 of purchased credit impaired loans.
Schedule of Internal Ratings of Loans	'
	The following summarizes the Company’s internal ratings of its loans held-for-investment by class of financing receivables and portfolio segments, which are the same, at September 30, 2014 and December 31, 2013 (in thousands):
	September 30,		Pass				Special				Substandard				Doubtful				Total
	2014						Mention
	Commercial		$	597,717			$	3,649			$	10,726			$	—			$	612,092
	Agricultural			86,272				93				353				—				86,718
	Real Estate			1,710,201				18,741				45,613				84				1,774,639
	Consumer			352,850				601				1,527				3				354,981
	Total		$	2,747,040			$	23,084			$	58,219			$	87			$	2,828,430
	December 31,		Pass				Special				Substandard				Doubtful				Total
	2013						Mention
	Commercial		$	584,547			$	3,032			$	9,151			$	—			$	596,730
	Agricultural			75,382				245				298				3				75,928
	Real Estate			1,609,242				20,773				48,352				147				1,678,514
	Consumer			330,870				639				1,595				9				333,113
	Total		$	2,600,041			$	24,689			$	59,396			$	159			$	2,684,285
Schedule of Past Due Loans	'
	At September 30, 2014 and December 31, 2013, the Company’s past due loans are as follows (in thousands):
	September 30,		15-59				60-89				Greater				Total Past				Current				Total Loans		90 Days
	2014		Days				Days				Than 90				Due										Past Due
			Past				Past				Days														Still
			Due*				Due																		Accruing
	Commercial		$	2,726			$	110			$	316			$	3,152			$	608,940			$	612,092	$	111
	Agricultural			294				59				—				353				86,365				86,718		—
	Real Estate			15,404				930				2,216				18,550				1,756,089				1,774,639		102
	Consumer			1,742				292				297				2,331				352,650				354,981		50
	Total		$	20,166			$	1,391			$	2,829			$	24,386			$	2,804,044			$	2,828,430	$	263
	December 31,		15-59				60-89				Greater				Total Past				Current				Total Loans		90 Days
	2013		Days				Days				Than 90				Due										Past Due
			Past				Past				Days														Still
			Due*				Due																		Accruing
	Commercial		$	5,303			$	287			$	420			$	6,010			$	590,720			$	596,730	$	—
	Agricultural			355				—				—				355				75,573				75,928		—
	Real Estate			13,787				2,489				1,876				18,152				1,660,362				1,678,514		55
	Consumer			2,708				582				277				3,567				329,546				333,113		78
	Total		$	22,153			$	3,358			$	2,573			$	28,084			$	2,656,201			$	2,684,285	$	133
	*	The Company monitors commercial, agricultural and real estate loans after such loans are 15 days past due. Consumer loans are monitored after such loans are 30 days past due.
Allowance for Loan Losses by Estimating Losses in Various Categories of Loan Portfolio	'
	The allowance for loan losses as of September 30, 2014 and 2013, and December 31, 2013, is presented below. Management has evaluated the appropriateness of the allowance for loan losses by estimating the probable losses in various categories of the loan portfolio, which are identified below (in thousands):
			September 30,								December 31,
			2014				2013				2013
	Allowance for loan losses provided for:
	Loans specifically evaluated as impaired		$	4,634			$	4,605			$	5,338
	Remaining portfolio			31,754				30,195				28,562
	Total allowance for loan losses		$	36,388			$	34,800			$	33,900
Schedule of Allowance for Loan Losses by Portfolio Segment	'
	The following table details the allowance for loan losses at September 30, 2014 and December 31, 2013 by portfolio segment (in thousands). There were no allowances for purchased credit impaired loans at September 30, 2014 or December 31, 2013. Allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories.
	September 30, 2014		Commercial				Agricultural				Real Estate				Consumer				Total
	Loans individually evaluated for impairment		$	2,837			$	127			$	7,081			$	388			$	10,433
	Loans collectively evaluated for impairment			4,649				258				19,218				1,830				25,955
	Total		$	7,486			$	385			$	26,299			$	2,218			$	36,388
	December 31, 2013		Commercial				Agricultural				Real Estate				Consumer				Total
	Loans individually evaluated for impairment		$	2,755			$	125			$	7,215			$	378			$	10,473
	Loans collectively evaluated for impairment			3,685				258				17,725				1,759				23,427
	Total		$	6,440			$	383			$	24,940			$	2,137			$	33,900
Changes in Allowance for Loan Losses	'
	Changes in the allowance for loan losses for the three and nine months ended September 30, 2014 and 2013 are summarized as follows by portfolio segment (in thousands):
	Three months ended		Commercial				Agricultural				Real Estate				Consumer				Total
	September 30, 2014
	Beginning balance		$	6,861			$	364			$	26,561			$	2,106			$	35,892
	Provision for loan losses			635				7				(80	)			334				896
	Recoveries			72				14				42				86				214
	Charge-offs			(82	)			—				(224	)			(308	)			(614	)
	Ending balance		$	7,486			$	385			$	26,299			$	2,218			$	36,388
	Three months ended		Commercial				Agricultural				Real Estate				Consumer				Total
	September 30, 2013
	Beginning balance		$	6,736			$	1,493			$	23,902			$	1,968			$	34,099
	Provision for loan losses			354				(999	)			1,644				350				1,349
	Recoveries			141				10				42				104				297
	Charge-offs			(218	)			(86	)			(294	)			(347	)			(945	)
	Ending balance		$	7,013			$	418			$	25,294			$	2,075			$	34,800
	Nine months ended		Commercial				Agricultural				Real Estate				Consumer				Total
	September 30, 2014
	Beginning balance		$	6,440			$	383			$	24,940			$	2,137			$	33,900
	Provision for loan losses			1,189				(14	)			1,988				547				3,710
	Recoveries			225				17				361				386				989
	Charge-offs			(368	)			(1	)			(990	)			(852	)			(2,211	)
	Ending balance		$	7,486			$	385			$	26,299			$	2,218			$	36,388
	Nine months ended		Commercial				Agricultural				Real Estate				Consumer				Total
	September 30, 2013
	Beginning balance		$	7,343			$	1,541			$	24,063			$	1,892			$	34,839
	Provision for loan losses			(77	)			(1,056	)			3,035				680				2,582
	Recoveries			329				29				95				266				719
	Charge-offs			(582	)			(96	)			(1,899	)			(763	)			(3,340	)
	Ending balance		$	7,013			$	418			$	25,294			$	2,075			$	34,800
Schedule of Investment in Loans Related to Balance in Allowance for Loan Losses on Basis of Company's Impairment Methodology	'
	The Company’s recorded investment in loans as of September 30, 2014 and December 31, 2013 related to the balance in the allowance for loan losses on the basis of the Company’s impairment methodology was as follows (in thousands). Purchased credit impaired loans of $2,383,000 and $2,707,000 at September 30, 2014 and December 31, 2013, respectively, are included in loans individually evaluated for impairment.
	September 30, 2014		Commercial				Agricultural				Real Estate				Consumer				Total
	Loans individually evaluated for impairment		$	14,375			$	446			$	64,438			$	2,131			$	81,390
	Loans collectively evaluated for impairment			597,717				86,272				1,710,201				352,850				2,747,040
	Total		$	612,092			$	86,718			$	1,774,639			$	354,981			$	2,828,430
	December 31, 2013		Commercial				Agricultural				Real Estate				Consumer				Total
	Loans individually evaluated for impairment		$	12,183			$	546			$	69,272			$	2,243			$	84,244
	Loans collectively evaluated for impairment			584,547				75,382				1,609,242				330,870				2,600,041
	Total		$	596,730			$	75,928			$	1,678,514			$	333,113			$	2,684,285
Schedule of Loans Modified and Considered Troubled Debt Restructurings	'
	The Company’s loans that were modified in the three and nine months ended September 30, 2014 and 2013 and considered troubled debt restructurings are as follows (in thousands):
			Three Months Ended September 30, 2014												Nine Months Ended September 30, 2014
							Pre-Modification				Post-Modification								Pre-Modification				Post-Modification
							Recorded				Recorded								Recorded				Recorded
			Number				Investment				Investment				Number				Investment				Investment
	Commercial			1			$	158			$	158				6			$	557			$	557
	Agricultural			—				—				—				1				39				39
	Real Estate			1				40				40				5				630				630
	Consumer			—				—				—				3				11				11
	Total			2			$	198			$	198				15			$	1,237			$	1,237
			Three Months Ended September 30, 2013												Nine Months Ended September 30, 2013
							Pre-Modification				Post-Modification								Pre-Modification				Post-Modification
							Recorded				Recorded								Recorded				Recorded
			Number				Investment				Investment				Number				Investment				Investment
	Commercial			—			$	—			$	—				3			$	218			$	218
	Agricultural			—				—				—				1				24				24
	Real Estate			—				—				—				8				3,779				3,779
	Consumer			4				86				86				5				123				123
	Total			4			$	86			$	86				17			$	4,144			$	4,144
Schedule of How Loans Were Modified as Troubled Debt Restructured Loans	'
	The balances below provide information as to how the loans were modified as troubled debt restructured loans during the three and nine months ended September 30, 2014 and 2013 (in thousands):
			Three Months Ended September 30, 2014												Nine Months Ended September 30, 2014
			Adjusted				Extended				Combined				Adjusted				Extended				Combined
			Interest				Maturity				Rate and				Interest				Maturity				Rate and
			Rate								Maturity				Rate								Maturity
	Commercial		$	—			$	158			$	—			$	—			$	255			$	302
	Agricultural			—				—				—				—				—				39
	Real Estate			—				—				40				—				118				512
	Consumer			—				—				—				—				8				3
	Total		$	—			$	158			$	40			$	—			$	381			$	856
			Three Months Ended September 30, 2013												Nine Months Ended September 30, 2013
			Adjusted				Extended				Combined				Adjusted				Extended				Combined
			Interest				Maturity				Rate and				Interest				Maturity				Rate and
			Rate								Maturity				Rate								Maturity
	Commercial		$	—			$	—			$	—			$	—			$	218			$	—
	Agricultural			—				—				—				—				24				—
	Real Estate			—				—				—				420				350				3,009
	Consumer			—				82				4				—				119				4
	Total		$	—			$	82			$	4			$	420			$	711			$	3,013
Schedule of Troubled Debt Restructurings	'
	The loans with payment default are as follows (dollars in thousands):
			Three Months Ended September 30,								Nine Months Ended September 30,
			2014								2014
			Number				Balance				Number				Balance
	Commercial			—			$	—				—			$	—
	Agriculture			—				—				—				—
	Real Estate			—				—				—				—
	Consumer			—				—				1				32
	Total			—			$	—				1			$	32
			Three Months Ended September 30,								Nine Months Ended September 30,
			2013								2013
			Number				Balance				Number				Balance
	Commercial			1			$	71				6			$	316
	Agriculture			—				—				—				—
	Real Estate			—				—				—				—
	Consumer			—				—				—				—
	Total			1			$	71				6			$	316

Fair_Value_Disclosures_Tables

Fair Value Disclosures (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Financial Assets and Financial Liabilities Measured at Fair Value on Recurring Basis	'
	The following table summarizes financial assets and financial liabilities measured at fair value on a recurring basis as of September 30, 2014, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value (dollars in thousands):
		Level 1			Level 2			Level 3		Total Fair
		Inputs			Inputs			Inputs		Value
	Available-for-sale investment securities:
	U.S. Treasury securities	$	520		$	—		$	—	$	520
	Obligations of U. S. government sponsored-enterprises and agencies		—			107,301			—		107,301
	Obligations of states and political subdivisions		18,546			1,083,423			—		1,101,969
	Corporate bonds		—			95,038			—		95,038
	Residential mortgage-backed securities		45,769			766,098			—		811,867
	Commercial mortgage-backed securities		—			132,412			—		132,412
	Other securities		4,655			—			—		4,655
	Total	$	69,490		$	2,184,272		$	—	$	2,253,762
Other Real Estate Owned	'
	The following table presents other real estate owned that were re-measured subsequent to their initial transfer to other real estate owned (dollars in thousands):
		Three Months Ended
		September 30,
		2014			2013
	Carrying value of other real estate owned prior to re-measurement	$	173		$	238
	Write-downs included in gain (loss) on sale of other real estate owned		(46	)		(65	)
	Fair value	$	127		$	173
		Nine Months Ended
		September 30,
		2014			2013
	Carrying value of other real estate owned prior to re-measurement	$	881		$	2,065
	Write-downs included in gain (loss) on sale of other real estate owned		(135	)		(369	)
	Fair value	$	746		$	1,696
Schedule of Estimated Fair Values and Carrying Values of All Financial Instruments	'
	The estimated fair values and carrying values of all financial instruments under current authoritative guidance at September 30, 2014 and December 31, 2013, were as follows (in thousands):
		September 30,						December 31,
		2014						2013
		Carrying			Estimated			Carrying		Estimated		Fair Value
		Value			Fair Value			Value		Fair Value		Hierarchy
	Cash and due from banks	$	149,957		$	149,957		$	183,084	$	183,084	Level 1
	Federal funds sold		4,785			4,785			3,430		3,430	Level 1
	Interest-bearing deposits in banks		83,994			83,994			25,498		25,498	Level 1
	Interest-bearing time deposits in banks		19,234			19,285			31,917		32,059	Level 2
	Available-for-sale securities		2,253,762			2,253,762			2,057,723		2,057,723	Levels 1 and 2
	Held-to-maturity securities		554			560			684		694	Level 2
	Loans		2,803,308			2,815,509			2,655,548		2,667,743	Level 3
	Accrued interest receivable		23,420			23,420			26,865		26,865	Level 2
	Deposits with stated maturities		664,221			666,123			686,627		688,876	Level 2
	Deposits with no stated maturities		3,800,143			3,800,143			3,448,448		3,448,448	Level 1
	Short term borrowings		341,909			341,909			463,888		463,888	Level 2
	Accrued interest payable		275			275			299		299	Level 2

Basis_of_Presentation_Addition

Basis of Presentation - Additional Information (Detail) (USD $)

9 Months Ended

9 Months Ended

9 Months Ended

Sep. 30, 2014

31-May-13

Sep. 30, 2014

Oct. 28, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

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Sep. 30, 2014

Sep. 30, 2014

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Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Location

Subsidiary of Common Parent [Member]

Subsequent Event [Member]

Abilene [Member]

Abilene [Member]

Cleburne [Member]

Stephenville [Member]

Stephenville [Member]

Granbury [Member]

San Angelo [Member]

San Angelo [Member]

Weatherford [Member]

Mineral Wells [Member]

Hereford [Member]

Sweetwater [Member]

Sweetwater [Member]

Eastland [Member]

Ranger [Member]

Rising Star [Member]

Cisco [Member]

Southlake [Member]

Grapevine [Member]

Aledo [Member]

Willow Park [Member]

Brock [Member]

Alvarado [Member]

Beaumont [Member]

Burleson [Member]

Keller [Member]

Trophy Club [Member]

Boyd [Member]

Bridgeport [Member]

Decatur [Member]

Roby [Member]

Trent [Member]

Merkel [Member]

Clyde [Member]

Moran [Member]

New Waverly [Member]

Albany [Member]

Midlothian [Member]

Glen Rose [Member]

Odessa [Member]

Odessa [Member]

Waxahachie [Member]

Acton [Member]

Fort Worth [Member]

Fort Worth [Member]

Orange [Member]

Orange [Member]

Newton [Member]

Port Arthur [Member]

Vidor [Member]

Mauriceville [Member]

Huntsville [Member]

Lubbock [Member]

Location

Maximum [Member]

Location

Subsidiary of Common Parent [Member]

Location

Location

Subsidiary of Common Parent [Member]

Location

Location

Subsidiary of Common Parent [Member]

Location

Location

Location

Location

Subsidiary of Common Parent [Member]

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

Location

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Location

Location

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Location

Location

Subsidiary of Common Parent [Member]

Location

Location

Location

Subsidiary of Common Parent [Member]

Location

Subsidiary of Common Parent [Member]

Location

Location

Location

Location

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Subsidiary of Common Parent [Member]

Location

Location

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Location

Location

Basis Of Presentation [Line Items]

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Number of locations

62

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8

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11

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2

2

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1

Percentage of common stock acquired

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100.00%

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Stock repurchase program, number of shares authorized to be repurchased

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1,500,000

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Stock repurchase program expiration date

30-Sep-17

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Minimum number of shares that company is required to repurchase

0

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Stock repurchased under authorization

0

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Impairment recorded

$0

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Stock_Split_Additional_Informa

Stock Split - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2014
Text Block [Abstract]	'
Stock split conversion ratio	'Two-for-one stock split
Percentage of stock dividend	100.00%
Dividend declared date	22-Apr-14
Dividend record date	15-May-14
Dividend distribution date	2-Jun-14

Earnings_Per_Share_Additional_

Earnings Per Share - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]	'	'	'	'
Weighted average common shares outstanding, basic	64,059,675	63,940,810	64,038,526	63,444,544
Weighted average common shares outstanding, diluted	64,304,985	64,243,542	64,302,615	63,706,588

Interestbearing_Time_Deposits_2

Interest-bearing Time Deposits in Banks and Securities - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
	Investment		Investment
Interest Bearing Time Deposits In Banks And Securities [Line Items]	'	'	'	'	'
INTEREST-BEARING TIME DEPOSITS IN BANKS	$19,234,000	$34,352,000	$19,234,000	$34,352,000	$31,917,000
Time deposits with balances greater than $100,000	17,699,000	'	17,699,000	'	29,002,000
Time deposits balances	'	'	100,000	'	100,000
Held-to-maturity securities	554,000	798,000	554,000	798,000	684,000
Number of investment positions	114	'	114	'	'
Securities pledged as collateral	1,430,183,000	'	1,430,183,000	'	'
Sales and calls of investment securities available-for-sale	2,145,000	50,065,000	3,590,000	121,420,000	'
Gross realized gains from security sales and calls	1,000	1,114,000	1,000	1,371,000	'
Gross realized losses from security sales and calls	$0	$1,222,000	$5,000	$1,224,000	'
Minimum [Member]	'	'	'	'	'
Interest Bearing Time Deposits In Banks And Securities [Line Items]	'	'	'	'	'
Interest-bearing time deposits, maturity period, years	'	'	'1 year	'	'
Maximum [Member]	'	'	'	'	'
Interest Bearing Time Deposits In Banks And Securities [Line Items]	'	'	'	'	'
Interest-bearing time deposits, maturity period, years	'	'	'2 years	'	'

Interestbearing_Time_Deposits_3

Interest-bearing Time Deposits in Banks and Securities - Summary of Available-for-Sale Securities (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]	'	'	'
Securities available-for-sale, Amortized Cost Basis	$2,187,272	$2,035,126	'
Securities available-for-sale, Gross Unrealized Holding Gains	75,057	45,455	'
Securities available-for-sale, Gross Unrealized Holding Losses	-8,567	-22,858	'
Securities available-for-sale, Estimated Fair Value	2,253,762	2,057,723	1,975,303
U.S. Treasury Securities [Member]	'	'	'
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]	'	'	'
Securities available-for-sale, Amortized Cost Basis	520	'	'
Securities available-for-sale, Estimated Fair Value	520	'	'
Obligations of U.S. Government Sponsored-Enterprises and Agencies [Member]	'	'	'
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]	'	'	'
Securities available-for-sale, Amortized Cost Basis	106,339	136,416	'
Securities available-for-sale, Gross Unrealized Holding Gains	964	1,672	'
Securities available-for-sale, Gross Unrealized Holding Losses	-2	'	'
Securities available-for-sale, Estimated Fair Value	107,301	138,088	'
Obligations of States and Political Subdivisions [Member]	'	'	'
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]	'	'	'
Securities available-for-sale, Amortized Cost Basis	1,046,148	974,608	'
Securities available-for-sale, Gross Unrealized Holding Gains	56,398	27,980	'
Securities available-for-sale, Gross Unrealized Holding Losses	-577	-11,319	'
Securities available-for-sale, Estimated Fair Value	1,101,969	991,269	'
Corporate Bonds and Other [Member]	'	'	'
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]	'	'	'
Securities available-for-sale, Amortized Cost Basis	96,424	105,490	'
Securities available-for-sale, Gross Unrealized Holding Gains	3,269	3,550	'
Securities available-for-sale, Estimated Fair Value	99,693	109,040	'
Residential Mortgage-Backed Securities [Member]	'	'	'
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]	'	'	'
Securities available-for-sale, Amortized Cost Basis	803,072	706,289	'
Securities available-for-sale, Gross Unrealized Holding Gains	14,395	12,253	'
Securities available-for-sale, Gross Unrealized Holding Losses	-5,600	-7,922	'
Securities available-for-sale, Estimated Fair Value	811,867	710,620	'
Commercial Mortgage-Backed Securities [Member]	'	'	'
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]	'	'	'
Securities available-for-sale, Amortized Cost Basis	134,769	112,323	'
Securities available-for-sale, Gross Unrealized Holding Gains	31	'	'
Securities available-for-sale, Gross Unrealized Holding Losses	-2,388	-3,617	'
Securities available-for-sale, Estimated Fair Value	$132,412	$108,706	'

Interestbearing_Time_Deposits_4

Interest-bearing Time Deposits in Banks and Securities - Amortized Cost and Estimated Fair Value of Available-for-Sale Securities (Detail) (USD $)	Sep. 30, 2014
In Thousands, unless otherwise specified
Investments, Debt and Equity Securities [Abstract]	'
Available-for-Sale, Amortized Cost Basis, Due within one year	$76,858
Available-for-Sale, Amortized Cost Basis, Due after one year through five years	663,151
Available-for-Sale, Amortized Cost Basis, Due after five years through ten years	502,028
Available-for-Sale, Amortized Cost Basis, Due after ten years	7,394
Available-for-Sale, Amortized Cost Basis, Mortgage-backed securities	937,841
Available-for-Sale, Amortized Cost Basis, Total	2,187,272
Available-for-Sale, Estimated Fair Value, Due within one year	77,722
Available-for-Sale, Estimated Fair Value, Due after one year through five years	695,484
Available-for-Sale, Estimated Fair Value, Due after five years through ten years	527,658
Available-for-Sale, Estimated Fair Value, Due after ten years	8,619
Available-for-Sale, Estimated Fair Value, Mortgage-backed securities	944,279
Available-for-Sale, Estimated Fair Value, Total	$2,253,762

Interestbearing_Time_Deposits_5

Interest-bearing Time Deposits in Banks and Securities - Continuous Unrealized-Loss Position of Available-for-Sale and Held-to-Maturity Securities (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule Of Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position [Line Items]	'	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Fair Value	$107,564	$653,523
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Unrealized Loss	505	22,213
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Fair Value	286,782	9,777
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Unrealized Loss	8,062	645
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Fair Value	394,346	663,300
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Unrealized Loss	8,567	22,858
Obligations of U.S. Government Sponsored-Enterprises and Agencies [Member]	'	'
Schedule Of Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position [Line Items]	'	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Fair Value	876	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Unrealized Loss	2	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Fair Value	876	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Unrealized Loss	2	'
Obligations of States and Political Subdivisions [Member]	'	'
Schedule Of Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position [Line Items]	'	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Fair Value	17,871	316,394
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Unrealized Loss	38	10,973
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Fair Value	50,158	4,153
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Unrealized Loss	539	346
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Fair Value	68,029	320,547
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Unrealized Loss	577	11,319
Residential Mortgage-Backed Securities [Member]	'	'
Schedule Of Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position [Line Items]	'	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Fair Value	82,382	228,423
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Unrealized Loss	450	7,623
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Fair Value	134,271	5,624
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Unrealized Loss	5,150	299
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Fair Value	216,653	234,047
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Unrealized Loss	5,600	7,922
Commercial Mortgage-Backed Securities [Member]	'	'
Schedule Of Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position [Line Items]	'	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Fair Value	6,435	108,706
Available-for-sale and held-to-maturity securities, continuous unrealized loss position Less than 12 Months, Unrealized Loss	15	3,617
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Fair Value	102,353	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position 12 Months or Longer, Unrealized Loss	2,373	'
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Fair Value	108,788	108,706
Available-for-sale and held-to-maturity securities, continuous unrealized loss position, Unrealized Loss	$2,388	$3,617

Loans_and_Allowance_for_Loan_L2

Loans and Allowance for Loan Losses - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Receivables [Abstract]	'	'	'	'
Minimum number of days to consider the loans as non-accrual	'	'Greater than 90 days	'	'
Carrying amount of purchased credit impaired loans	'	$2,383,000	$2,954,000	$2,707,000
Contractual balance	3,525,000	3,525,000	4,218,000	3,970,000
Loans held for sale	11,266,000	11,266,000	5,724,000	5,163,000
Average recorded investment in impaired loans	24,893,000	26,524,000	22,530,000	31,293,000
Non-accrual loans still accruing, past due 90 days, restructured loans and foreclosed assets	23,629,000	23,629,000	28,535,000	31,128,000
Additional funds advanced in connection with impaired loans	0	0	'	'
Interest income recognized on impaired loans	'	0	'	685,000
Allowance for purchased credit impaired loans	0	0	'	0
Default for purposes of this disclosure is a troubled debt restructured loan	'	'90 days	'	'
Commitments to lend additional funds to borrowers with loan that have been modified as TDRs	0	0	'	'
Loans held by subsidiaries subject to blanket liens	1,634,405,000	1,634,405,000	'	'
Letters of credit outstanding, amount	7,000,000	7,000,000	'	'
Short-term borrowings outstanding	$1,038,000	$1,038,000	'	'

Loans_and_Allowance_for_Loan_L3

Loans and Allowance for Loan Losses - Loans Held-for-Investment by Class of Financing Receivables (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Receivables [Abstract]	'	'	'
Commercial	$612,092	$596,730	$571,973
Agricultural	86,718	75,928	66,758
Real estate	1,774,639	1,678,514	1,640,308
Consumer	354,981	333,113	330,046
Total	$2,828,430	$2,684,285	$2,609,085

Loans_and_Allowance_for_Loan_L4

Loans and Allowance for Loan Losses - Non-Accrual Loans, Loans Still Accruing and Past Due 90 Days or More and Restructured Loans (Detail) (USD $)	9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Receivables [Abstract]	'	'	'
Non-accrual loans	$22,093	$22,809	$27,926
Loans still accruing and past due 90 days or more	263	54	133
Troubled debt restructured loans	'	'	'
Total	$22,356	$22,863	$28,059

Loans_and_Allowance_for_Loan_L5

Loans and Allowance for Loan Losses - Non-Accrual Loans, Loans Still Accruing and Past Due 90 Days or More and Restructured Loans (Parenthetical) (Detail) (USD $)	9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Receivables [Abstract]	'	'	'
Carrying amount of purchased credit impaired loans	$2,383,000	$2,954,000	$2,707,000
Troubled debt restructured loans	$10,114,000	$14,737,000	$13,298,000

Loans_and_Allowance_for_Loan_L6

Loans and Allowance for Loan Losses - Recorded Investment in Impaired Loans and Related Valuation Allowance (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Receivables [Abstract]	'	'	'
Recorded Investment	$22,093	$27,926	$22,809
Valuation Allowance	$4,634	$5,338	$4,605

Loans_and_Allowance_for_Loan_L7

Loans and Allowance for Loan Losses - Schedule of Non-Accrual Loans (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Non-accrual loans	$22,093	$27,926	$22,809
Agriculture [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Non-accrual loans	102	131	97
Real Estate [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Non-accrual loans	17,712	22,548	20,036
Commercial [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Non-accrual loans	3,481	4,281	1,986
Consumer [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Non-accrual loans	$798	$966	$690

Loans_and_Allowance_for_Loan_L8

Loans and Allowance for Loan Losses - Schedule of Impaired Loans and Related Allowance (Detail) (USD $)	3 Months Ended	9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'	'
Unpaid Contractual Principal Balance	$28,577	$28,577	$28,559	$37,724
Recorded Investment With No Allowance	6,291	6,291	5,294	7,290
Recorded Investment With Allowance	15,802	15,802	17,515	20,636
Total Recorded Investment	22,093	22,093	22,809	27,926
Related Allowance	4,634	4,634	4,605	5,338
Average Recorded Investment	24,893	26,524	22,530	31,293
Three-month Average Recorded Investment	'	24,893	23,768	'
Agriculture [Member]	'	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'	'
Unpaid Contractual Principal Balance	113	113	105	139
Recorded Investment With No Allowance	'	'	91	17
Recorded Investment With Allowance	102	102	6	114
Total Recorded Investment	102	102	97	131
Related Allowance	37	37	6	41
Average Recorded Investment	'	113	104	144
Three-month Average Recorded Investment	'	104	99	'
Real Estate [Member]	'	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'	'
Unpaid Contractual Principal Balance	23,559	23,559	25,085	31,704
Recorded Investment With No Allowance	5,546	5,546	4,290	5,794
Recorded Investment With Allowance	12,166	12,166	15,746	16,753
Total Recorded Investment	17,712	17,712	20,036	22,547
Related Allowance	3,256	3,256	3,628	4,006
Average Recorded Investment	'	21,510	19,985	25,060
Three-month Average Recorded Investment	'	20,212	20,757	'
Commercial [Member]	'	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'	'
Unpaid Contractual Principal Balance	3,928	3,928	2,545	4,764
Recorded Investment With No Allowance	278	278	701	934
Recorded Investment With Allowance	3,203	3,203	1,285	3,348
Total Recorded Investment	3,481	3,481	1,986	4,282
Related Allowance	1,160	1,160	710	1,079
Average Recorded Investment	'	3,990	1,779	5,017
Three-month Average Recorded Investment	'	3,713	2,113	'
Consumer [Member]	'	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'	'
Unpaid Contractual Principal Balance	977	977	824	1,117
Recorded Investment With No Allowance	467	467	212	545
Recorded Investment With Allowance	331	331	478	421
Total Recorded Investment	798	798	690	966
Related Allowance	181	181	261	212
Average Recorded Investment	'	911	662	1,072
Three-month Average Recorded Investment	'	$864	$799	'

Loans_and_Allowance_for_Loan_L9

Loans and Allowance for Loan Losses - Schedule of Impaired Loans and Related Allowance (Parenthetical) (Detail) (USD $)	9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Receivables [Abstract]	'	'	'
Carrying amount of purchased credit impaired loans	$2,383,000	$2,954,000	$2,707,000

Recovered_Sheet1

Loans and Allowance for Loan Losses - Schedule of Internal Ratings of Loans (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	$2,828,430	$2,684,285	$2,609,085
Commercial [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	612,092	596,730	'
Agriculture [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	86,718	75,928	'
Real Estate [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	1,774,639	1,678,514	'
Consumer [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	354,981	333,113	'
Pass [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	2,747,040	2,600,041	'
Pass [Member] | Commercial [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	597,717	584,547	'
Pass [Member] | Agriculture [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	86,272	75,382	'
Pass [Member] | Real Estate [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	1,710,201	1,609,242	'
Pass [Member] | Consumer [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	352,850	330,870	'
Special Mention [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	23,084	24,689	'
Special Mention [Member] | Commercial [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	3,649	3,032	'
Special Mention [Member] | Agriculture [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	93	245	'
Special Mention [Member] | Real Estate [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	18,741	20,773	'
Special Mention [Member] | Consumer [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	601	639	'
Substandard [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	58,219	59,396	'
Substandard [Member] | Commercial [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	10,726	9,151	'
Substandard [Member] | Agriculture [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	353	298	'
Substandard [Member] | Real Estate [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	45,613	48,352	'
Substandard [Member] | Consumer [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	1,527	1,595	'
Doubtful [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	87	159	'
Doubtful [Member] | Agriculture [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	'	3	'
Doubtful [Member] | Real Estate [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	84	147	'
Doubtful [Member] | Consumer [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
Internal ratings of loan	$3	$9	'

Recovered_Sheet2

Loans and Allowance for Loan Losses - Schedule of Past Due Loans (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
15-59 Days Past Due	$20,166	$22,153	'
60-89 Days Past Due	1,391	3,358	'
Greater Than 90 Days	2,829	2,573	'
Total Past Due	24,386	28,084	'
Total Current	2,804,044	2,656,201	'
Total	2,828,430	2,684,285	2,609,085
Total 90 Days Past Due Still Accruing	263	133	'
Agriculture [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
15-59 Days Past Due	294	355	'
60-89 Days Past Due	59	'	'
Total Past Due	353	355	'
Total Current	86,365	75,573	'
Total	86,718	75,928	'
Real Estate [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
15-59 Days Past Due	15,404	13,787	'
60-89 Days Past Due	930	2,489	'
Greater Than 90 Days	2,216	1,876	'
Total Past Due	18,550	18,152	'
Total Current	1,756,089	1,660,362	'
Total	1,774,639	1,678,514	'
Total 90 Days Past Due Still Accruing	102	55	'
Commercial [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
15-59 Days Past Due	2,726	5,303	'
60-89 Days Past Due	110	287	'
Greater Than 90 Days	316	420	'
Total Past Due	3,152	6,010	'
Total Current	608,940	590,720	'
Total	612,092	596,730	'
Total 90 Days Past Due Still Accruing	111	'	'
Consumer [Member]	'	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'	'
15-59 Days Past Due	1,742	2,708	'
60-89 Days Past Due	292	582	'
Greater Than 90 Days	297	277	'
Total Past Due	2,331	3,567	'
Total Current	352,650	329,546	'
Total	354,981	333,113	'
Total 90 Days Past Due Still Accruing	$50	$78	'

Recovered_Sheet3

Loans and Allowance for Loan Losses - Allowance for Loan Losses by Estimating Losses in Various Categories of Loan Portfolio (Detail) (USD $)	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Receivables [Abstract]	'	'	'	'	'	'
Loans specifically evaluated as impaired	$4,634	'	$5,338	$4,605	'	'
Remaining portfolio	31,754	'	28,562	30,195	'	'
Total allowance for loan losses	$36,388	$35,892	$33,900	$34,800	$34,099	$34,839

Recovered_Sheet4

Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses by Portfolio Segment (Detail) (USD $)	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'
Loans individually evaluated for impairment	$10,433	'	$10,473	'	'	'
Loans collectively evaluated for impairment	25,955	'	23,427	'	'	'
Total allowance for loan losses	36,388	35,892	33,900	34,800	34,099	34,839
Real Estate [Member]	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'
Loans individually evaluated for impairment	7,081	'	7,215	'	'	'
Loans collectively evaluated for impairment	19,218	'	17,725	'	'	'
Total allowance for loan losses	26,299	'	24,940	'	'	'
Agriculture [Member]	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'
Loans individually evaluated for impairment	127	'	125	'	'	'
Loans collectively evaluated for impairment	258	'	258	'	'	'
Total allowance for loan losses	385	364	383	418	1,493	1,541
Commercial [Member]	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'
Loans individually evaluated for impairment	2,837	'	2,755	'	'	'
Loans collectively evaluated for impairment	4,649	'	3,685	'	'	'
Total allowance for loan losses	7,486	6,861	6,440	7,013	6,736	7,343
Consumer [Member]	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'
Loans individually evaluated for impairment	388	'	378	'	'	'
Loans collectively evaluated for impairment	1,830	'	1,759	'	'	'
Total allowance for loan losses	$2,218	$2,106	$2,137	$2,075	$1,968	$1,892

Recovered_Sheet5

Loans and Allowance for Loan Losses - Changes in Allowance for Loan Losses (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	$35,892	$34,099	$33,900	$34,839
Provision for loan losses	896	1,349	3,710	2,582
Recoveries	214	297	989	719
Charge-offs	-614	-945	-2,211	-3,340
Ending balance	36,388	34,800	36,388	34,800
Real Estate [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	26,561	23,902	24,940	24,063
Provision for loan losses	-80	1,644	1,988	3,035
Recoveries	42	42	361	95
Charge-offs	-224	-294	-990	-1,899
Ending balance	26,299	25,294	26,299	25,294
Agriculture [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	364	1,493	383	1,541
Provision for loan losses	7	-999	-14	-1,056
Recoveries	14	10	17	29
Charge-offs	'	-86	-1	-96
Ending balance	385	418	385	418
Commercial [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	6,861	6,736	6,440	7,343
Provision for loan losses	635	354	1,189	-77
Recoveries	72	141	225	329
Charge-offs	-82	-218	-368	-582
Ending balance	7,486	7,013	7,486	7,013
Consumer [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	2,106	1,968	2,137	1,892
Provision for loan losses	334	350	547	680
Recoveries	86	104	386	266
Charge-offs	-308	-347	-852	-763
Ending balance	$2,218	$2,075	$2,218	$2,075

Recovered_Sheet6

Loans and Allowance for Loan Losses - Schedule of Investment in Loans Related to Balance in Allowance for Loan Losses on Basis of Company's Impairment Methodology (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Schedule Of Allowance For Credit Losses And Recorded Investment In Financing Receivables [Line Items]	'	'	'
Loans individually evaluated for impairment	$81,390	$84,244	'
Loans collectively evaluated for impairment	2,747,040	2,600,041	'
Total	2,828,430	2,684,285	2,609,085
Agriculture [Member]	'	'	'
Schedule Of Allowance For Credit Losses And Recorded Investment In Financing Receivables [Line Items]	'	'	'
Loans individually evaluated for impairment	446	546	'
Loans collectively evaluated for impairment	86,272	75,382	'
Total	86,718	75,928	'
Real Estate [Member]	'	'	'
Schedule Of Allowance For Credit Losses And Recorded Investment In Financing Receivables [Line Items]	'	'	'
Loans individually evaluated for impairment	64,438	69,272	'
Loans collectively evaluated for impairment	1,710,201	1,609,242	'
Total	1,774,639	1,678,514	'
Commercial [Member]	'	'	'
Schedule Of Allowance For Credit Losses And Recorded Investment In Financing Receivables [Line Items]	'	'	'
Loans individually evaluated for impairment	14,375	12,183	'
Loans collectively evaluated for impairment	597,717	584,547	'
Total	612,092	596,730	'
Consumer [Member]	'	'	'
Schedule Of Allowance For Credit Losses And Recorded Investment In Financing Receivables [Line Items]	'	'	'
Loans individually evaluated for impairment	2,131	2,243	'
Loans collectively evaluated for impairment	352,850	330,870	'
Total	$354,981	$333,113	'

Recovered_Sheet7

Loans and Allowance for Loan Losses - Schedule of Loans Modified and Considered Troubled Debt Restructurings (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
	SecurityLoan	SecurityLoan	SecurityLoan	SecurityLoan
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Number	2	4	15	17
Pre-Modification Recorded Investment	$198	$86	$1,237	$4,144
Post-Modification Recorded Investment	198	86	1,237	4,144
Agriculture [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Number	'	'	1	1
Pre-Modification Recorded Investment	'	'	39	24
Post-Modification Recorded Investment	'	'	39	24
Real Estate [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Number	1	'	5	8
Pre-Modification Recorded Investment	40	'	630	3,779
Post-Modification Recorded Investment	40	'	630	3,779
Commercial [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Number	1	'	6	3
Pre-Modification Recorded Investment	158	'	557	218
Post-Modification Recorded Investment	158	'	557	218
Consumer [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Number	'	4	3	5
Pre-Modification Recorded Investment	'	86	11	123
Post-Modification Recorded Investment	'	$86	$11	$123

Recovered_Sheet8

Loans and Allowance for Loan Losses - Schedule of How Loans Were Modified as Troubled Debt Restructured Loans (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Adjusted Interest Rate	'	'	'	$420
Extended Maturity	158	82	381	711
Combined Rate and Maturity	40	4	856	3,013
Commercial [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Extended Maturity	158	'	255	218
Combined Rate and Maturity	'	'	302	'
Agriculture [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Extended Maturity	'	'	'	24
Combined Rate and Maturity	'	'	39	'
Real Estate [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Adjusted Interest Rate	'	'	'	420
Extended Maturity	'	'	118	350
Combined Rate and Maturity	40	'	512	3,009
Consumer [Member]	'	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'	'
Extended Maturity	'	82	8	119
Combined Rate and Maturity	'	$4	$3	$4

Recovered_Sheet9

Loans and Allowance for Loan Losses - Schedule of Troubled Debt Restructurings (Detail) (USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
	Contract	Contract	Contract
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'
Number	1	1	6
Balance	$71	$32	$316
Commercial [Member]	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'
Number	1	'	6
Balance	71	'	316
Consumer [Member]	'	'	'
Troubled Debt Restructured Loan Modifications by Class [Line Items]	'	'	'
Number	'	1	'
Balance	'	$32	'

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Tax Disclosure [Abstract]	'	'	'	'
Income tax expense	$7,843	$6,121	$21,705	$18,723
Effective tax rates on pre-tax income	25.08%	23.83%	24.48%	24.52%
Statutory federal tax rate	'	'	35.00%	'

Stock_Based_Compensation_Addit

Stock Based Compensation - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	Oct. 22, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Oct. 22, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'	'	'	'	'	'
Stock option expense	'	$174,000	$88,000	$532,000	$264,000	'
Employees incentive stock option, shares	395,000	'	'	0	'	'
Employees incentive stock option, exercise price	'	'	'	'	'	$30.85

Pension_Plan_Additional_Inform

Pension Plan - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended	1 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Oct. 31, 2014
						Subsequent Event [Member]
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'	'	'
Contribution towards pension plan	'	'	$0	'	$1,000,000	'
Payment description	'	'	'	'	'	'The Company approved a plan to offer plan participants that are no longer employed by the Company the option to receive a one-time lump sum payment in lieu of future benefits to be received under the plan.
Net periodic benefit costs, total	$107,000	$208,000	$321,000	$623,000	'	'

Fair_Value_Disclosures_Additio

Fair Value Disclosures - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]	'	'	'	'	'
Assets transfer between Level 2 and Level 3	$0	$0	$0	$0	'
Impaired loans carrying value	22,093,000	22,809,000	22,093,000	22,809,000	27,926,000
Impaired loans valuation reserves	4,634,000	'	4,634,000	'	'
Impaired loans net fair value	17,459,000	'	17,459,000	'	'
Other real estate owned, total	$1,185,000	$5,490,000	$1,185,000	$5,490,000	$2,903,000
Minimum [Member]	'	'	'	'	'
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]	'	'	'	'	'
Debt discounts, percentage	'	'	5.00%	'	'
Maximum [Member]	'	'	'	'	'
Fair Value Inputs Assets And Liabilities Quantitative Information [Line Items]	'	'	'	'	'
Debt discounts, percentage	'	'	25.00%	'	'

Fair_Value_Disclosures_Financi

Fair Value Disclosures - Financial Assets and Financial Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	$2,253,762	$2,057,723	$1,975,303
U.S. Treasury Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	520	'	'
Obligations of U.S. Government Sponsored-Enterprises and Agencies [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	107,301	138,088	'
Obligations of States and Political Subdivisions [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	1,101,969	991,269	'
Corporate Bonds [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	95,038	'	'
Residential Mortgage-Backed Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	811,867	710,620	'
Commercial Mortgage-Backed Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	132,412	108,706	'
Other Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	4,655	'	'
Level 1 Inputs [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	69,490	'	'
Level 1 Inputs [Member] | U.S. Treasury Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	520	'	'
Level 1 Inputs [Member] | Obligations of States and Political Subdivisions [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	18,546	'	'
Level 1 Inputs [Member] | Residential Mortgage-Backed Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	45,769	'	'
Level 1 Inputs [Member] | Other Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	4,655	'	'
Level 2 Inputs [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	2,184,272	'	'
Level 2 Inputs [Member] | Obligations of U.S. Government Sponsored-Enterprises and Agencies [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	107,301	'	'
Level 2 Inputs [Member] | Obligations of States and Political Subdivisions [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	1,083,423	'	'
Level 2 Inputs [Member] | Corporate Bonds [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	95,038	'	'
Level 2 Inputs [Member] | Residential Mortgage-Backed Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	766,098	'	'
Level 2 Inputs [Member] | Commercial Mortgage-Backed Securities [Member]	'	'	'
Available-for-sale investment securities:	'	'	'
Available-for-sale investment securities, Total Fair Value	$132,412	'	'

Fair_Value_Disclosures_Other_R

Fair Value Disclosures - Other Real Estate Owned (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'	'	'	'
Carrying value of other real estate owned prior to re-measurement	$173	$238	$881	$2,065
Write-downs included in gain (loss) on sale of other real estate owned	-46	-65	-135	-369
Fair value	$127	$173	$746	$1,696

Fair_Value_Disclosures_Schedul

Fair Value Disclosures - Schedule of Estimated Fair Values and Carrying Values of All Financial Instruments (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
CASH AND DUE FROM BANKS	$149,957	$183,084	$164,666
FEDERAL FUNDS SOLD	4,785	3,430	14,300
INTEREST-BEARING DEPOSITS IN BANKS	83,994	25,498	48,634
INTEREST-BEARING TIME DEPOSITS IN BANKS	19,234	31,917	34,352
Available-for-sale securities	2,253,762	2,057,723	1,975,303
Held-to-maturity securities	554	684	798
Loans	2,803,308	2,655,548	2,580,009
Short term borrowings	341,909	463,888	466,500
Level 1 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Available-for-sale securities	69,490	'	'
Level 2 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Available-for-sale securities	2,184,272	'	'
Carrying Value [Member] | Level 1 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
CASH AND DUE FROM BANKS	149,957	183,084	'
FEDERAL FUNDS SOLD	4,785	3,430	'
INTEREST-BEARING DEPOSITS IN BANKS	83,994	25,498	'
Deposits with no stated maturities	3,800,143	3,448,448	'
Carrying Value [Member] | Level 2 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
INTEREST-BEARING TIME DEPOSITS IN BANKS	19,234	31,917	'
Held-to-maturity securities	554	684	'
Accrued interest receivable	23,420	26,865	'
Deposits with stated maturities	664,221	686,627	'
Short term borrowings	341,909	463,888	'
Accrued interest payable	275	299	'
Carrying Value [Member] | Levels 1 and 2 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Available-for-sale securities	2,253,762	2,057,723	'
Carrying Value [Member] | Level 3 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Loans	2,803,308	2,655,548	'
Estimated Fair Value [Member] | Level 1 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
CASH AND DUE FROM BANKS	149,957	183,084	'
FEDERAL FUNDS SOLD	4,785	3,430	'
INTEREST-BEARING DEPOSITS IN BANKS	83,994	25,498	'
Deposits with no stated maturities	3,800,143	3,448,448	'
Estimated Fair Value [Member] | Level 2 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
INTEREST-BEARING TIME DEPOSITS IN BANKS	19,285	32,059	'
Held-to-maturity securities	560	694	'
Accrued interest receivable	23,420	26,865	'
Deposits with stated maturities	666,123	688,876	'
Short term borrowings	341,909	463,888	'
Accrued interest payable	275	299	'
Estimated Fair Value [Member] | Levels 1 and 2 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Available-for-sale securities	2,253,762	2,057,723	'
Estimated Fair Value [Member] | Level 3 Inputs [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Loans	$2,815,509	$2,667,743	'