Fair Value of Financial Instruments (Details 3) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Financial assets
Cash and cash equivalents	$ 129,041	$ 105,091
Available for sale securities, Fair Value	2,784,415	2,395,847
Loans held for sale	35,440	76,213
Loans receivable, net of allowance for loan and lease losses	3,462,016	3,612,182
Accrued interest receivable	35,229	30,246
Financial liabilities
Federal Home Loan Bank advances	925,061	965,141
Accrued interest payable	6,261	7,245
Subordinated debentures	125,203	125,132
Carrying Amount [Member]
Financial assets
Cash and cash equivalents	129,041	105,091
Available for sale securities, Fair Value	2,784,415	2,395,847
Loans held for sale	35,440	76,213
Loans receivable, net of allowance for loan and lease losses	3,462,016	3,612,182
Accrued interest receivable	35,229	30,246
Non Marketable Equity Securities	50,762	65,040
Total financial assets	6,496,903	6,284,619
Financial liabilities
Deposits	4,704,799	4,521,902
Federal Home Loan Bank advances	925,061	965,141
Repurchase agreements, federal funds purchased and other borrowed funds	314,102	269,408
Accrued interest payable	6,261	7,245
Subordinated debentures	125,203	125,132
Total financial liabilities	6,075,426	5,888,828
Fair Value [Member]
Financial assets
Cash and cash equivalents	129,041	105,091
Available for sale securities, Fair Value	2,784,415	2,395,847
Loans held for sale	35,440	76,213
Loans receivable, net of allowance for loan and lease losses	3,514,290	3,631,716
Accrued interest receivable	35,229	30,246
Non Marketable Equity Securities	50,762	65,040
Total financial assets	6,549,177	6,304,153
Financial liabilities
Deposits	4,714,635	4,533,974
Federal Home Loan Bank advances	938,708	974,853
Repurchase agreements, federal funds purchased and other borrowed funds	314,104	269,414
Accrued interest payable	6,261	7,245
Subordinated debentures	69,529	70,404
Total financial liabilities	$ 6,043,237	$ 5,855,890

Total Financial Assets.

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Total Financial Liabilities.

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Financial Liabilities Abstract.

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Non marketable securities equity securities.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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