CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
OPERATING ACTIVITIES:
Net income	$ 40,491	$ 40,058	$ 45,863
Adjustments to reconcile net income to net cash provided by operations:
Depreciation	3,365	3,204	2,888
Amortization of premium	37,117	35,245	15,393
Accretion of discount and loan fees	(4,336)	(4,502)	(3,913)
Provision for loan losses	7,496	13,737	15,093
Stock compensation expense	261	0	0
Deferred tax (benefit) expense	(1,254)	673	(1,642)
Gain on sale of securities carried at fair value through income	(937)	0	0
Gain on sale of securities available for sale	(11,795)	(25,789)	(33,446)
Net other-than-temporary impairment losses	0	75	3,000
Fair value (gain) loss - securities	(6,693)	598	0
FHLB advance option impairment charges	8,923	0	0
Gain on sale of assets	(4)	(7)	0
Loss on retirement of assets	90	0	171
Impairment on other real estate owned	264	20	729
(Gain) loss on sale of other real estate owned	(298)	153	52
Net Change in:
Interest receivable	(1,393)	449	(2,130)
Other assets	(2,254)	(8,289)	(12,239)
Interest payable	(888)	(879)	(1,621)
Other liabilities	2,396	1,566	(944)
Loans held for sale	3,031	(3,726)	(2,346)
Net cash provided by operating activities	73,582	52,586	24,908
Securities held to maturity:
Purchases	(11,875)	(258,935)	(139,228)
Maturities, calls and principal repayments	46,396	74,915	51,167
Securities available for sale:
Purchases	(629,911)	(1,399,085)	(1,484,005)
Sales	582,362	1,325,221	978,610
Maturities, calls and principal repayments	268,514	357,164	324,558
Securities carried at fair value through income:
Purchases	(868,937)	(32,689)	0
Sales	234,403	0	0
Maturities, calls and principal repayments	56,406	3,462	0
Proceeds from redemption of FHLB stock	18,236	6,818	3,698
Purchases of FHLB stock and other investments	(17,393)	(2,900)	(2,916)
Net increase in loans	(21,898)	(58,985)	(26,657)
Purchases of premises and equipment	(3,915)	(6,902)	(6,814)
Proceeds from sales of premises and equipment	13	38	0
Proceeds on bank owned life insurance	0	0	1,086
Proceeds from sales of other real estate owned	1,431	1,648	1,102
Proceeds from sales of repossessed assets	4,820	4,949	2,900
Net cash (used in) provided by investing activities	(341,348)	14,719	(296,499)
FINANCING ACTIVITIES:
Net increase in demand and savings accounts	150,439	190,323	94,798
Net increase in certificates of deposit	40,842	87,268	199,521
Net (decrease) increase in federal funds purchased and repurchase agreements	(899)	(9,481)	2,696
Proceeds from FHLB advances	13,270,293	8,949,688	7,961,046
Repayment of FHLB advances	(13,210,331)	(9,241,985)	(7,991,050)
Net capital distributions to noncontrolling interest in consolidated entities	(475)	(310)	(1,471)
Purchase of noncontrolling interest	(4,750)	0	0
Tax benefit of incentive stock options	2	331	651
Purchase of common stock	0	(4,832)	(430)
Proceeds from the issuance of common stock	1,481	1,823	2,300
Dividends paid	(14,671)	(13,223)	(11,078)
Net cash provided by (used in) financing activities	231,931	(40,398)	256,983
Net (decrease) increase in cash and cash equivalents	(35,835)	26,907	(14,608)
Cash and cash equivalents at beginning of year	79,073	52,166	66,774
Cash and cash equivalents at end of year	43,238	79,073	52,166
SUPPLEMENTAL DISCLOSURES FOR CASH FLOW INFORMATION:
Interest paid	36,519	46,186	54,293
Income taxes paid	9,000	10,650	17,500
SUPPLEMENTAL DISCLOSURES OF NONCASH INVESTING AND FINANCING ACTIVITIES:
Acquisition of other repossessed assets and real estate through foreclosure	6,232	6,990	8,560
Adjustment to pension liability	8,382	5,531	(4,099)
5% stock dividend	15,995	15,513	13,527
Unsettled trades to purchase securities	(1,196)	(145)	(2,573)
Unsettled trades to sell securities	0	0	8,084
Unsettled issuances of brokered CDs	$ 0	$ 4,960	$ 19,842