UNAUDITED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss, net of tax [Member]	ESOP [Member]	Unearned Restricted Stock Award Common Stock [Member]	Treasury Stock [Member]	Common Stock Held by BMP [Member]
Balance at Dec. 31, 2010		$ 512	$ 225,585	$ 329,668	$ (6,352)	$ (3,470)	$ (2,684)	$ (206,546)	$ (7,979)
Stock options exercised		3	2,627
Forfeited restricted stock award shares returned to treasury stock			2				22	(24)
Tax benefit of stock plans			399
BMP award distribution									0
Amortization of excess fair value over cost - ESOP stock and stock options expense			1,082
Release from treasury stock for restricted stock award and BMP benefit shares			501				(1,953)	2,128	(676)
Net income	34,582			34,582
Cash dividends declared and paid				(14,156)
Amortization and reversal of net unrealized loss on securities transferred from available-for-sale to held-to-maturity, net of tax					47
Reduction in non credit component of OTTI charge, net of taxes	693				693
Non-credit component of OTTI charge recognized during the period, net of tax					(13)
Change in unrealized gain or loss on available-for-sale securities during the period					(545)
Adjustments to other comprehensive income from defined benefit plans, net of tax	(27)				27
Amortization of earned portion of ESOP stock						173
Amortization of earned portion of restricted stock awards							1,139
Balance at Sep. 30, 2011	354,792	515	230,196	350,094	(6,143)	(3,297)	(3,476)	(204,442)	(8,655)
Balance at Dec. 31, 2011	361,034	516	231,521	358,079	(9,709)	(3,239)	(3,037)	(204,442)	(8,655)
Stock options exercised		3	4,083
Forfeited restricted stock award shares returned to treasury stock			(3)				32	(29)
Tax benefit of stock plans			349
BMP award distribution									0
Amortization of excess fair value over cost - ESOP stock and stock options expense			1,025
Release from treasury stock for restricted stock award and BMP benefit shares			217				(1,959)	1,887	(145)
Net income	33,573			33,573
Cash dividends declared and paid				(14,386)
Amortization and reversal of net unrealized loss on securities transferred from available-for-sale to held-to-maturity, net of tax					91
Reduction in non credit component of OTTI charge, net of taxes	161				161
Non-credit component of OTTI charge recognized during the period, net of tax					(3)
Change in unrealized gain or loss on available-for-sale securities during the period					(248)
Adjustments to other comprehensive income from defined benefit plans, net of tax	(312)				312
Amortization of earned portion of ESOP stock						174
Amortization of earned portion of restricted stock awards							1,370
Balance at Sep. 30, 2012	$ 387,538	$ 519	$ 237,192	$ 377,266	$ (9,396)	$ (3,065)	$ (3,594)	$ (202,584)	$ (8,800)