Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2012

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis

Financial assets and financial liabilities measured at fair value on a recurring basis are as follows:

	Fair Value Measurements at Reporting Date Using
As of December 31, 2012	Balance		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Investment securities available-for-sale:
Obligations of U.S. government agencies	$	754,856	$	—	$	754,856	$	—
U.S. agencies mortgage-backed securities & collateralized mortgage obligations	1,239,851		—		1,239,851		—
Private mortgage-backed securities	551		—		551		—
Mortgage servicing rights	16,373		—		16,373		—

	Fair Value Measurements at Reporting Date Using
As of December 31, 2011	Balance		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Investment securities available-for-sale:
Obligations of U.S. government agencies	$	1,138,118	$	—	$	1,138,118	$	—
U.S. agencies mortgage-backed securities & collateralized mortgage obligations	877,997		—		877,997		—
Private mortgage-backed securities	749		—		749		—
Mortgage servicing rights	11,910		—		11,910		—
Derivative liability contract	383		—		—		383

Schedule of Derivative Liability Contract Measured at Fair Value on a Recurring Basis Unobservable Input Reconciliation

The following table reconciles the beginning and ending balances of the derivative liability contract measured at fair value on a recurring basis using significant unobservable (Level 3) inputs during the twelve months ended December 31, 2012 and 2011:

For the Twelve Months Ended December 31,	2012			2011
Balance, beginning of period	$	383		$	86
Accruals during the period	—			425
Cash payments during the period	(383		)	(128		)
Balance, end of period	$	—		$	383

Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Non-Recurring Basis

The following table presents information about the Company’s assets and liabilities measured at fair value on a non-recurring basis.

			Fair Value Measurements at Reporting Date Using
			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Total Gains (Losses)
	Total		(Level 1)		(Level 2)		(Level 3)
As of December 31, 2012
Impaired loans	$	74,623	$	—	$	—	$	74,623	$	(32,624	)
Other real estate owned	15,745		—		—		15,745		(20,797		)
As of December 31, 2011
Impaired loans	$	100,035	$	—	$	—	$	100,035	$	(67,043	)
Other real estate owned	17,000		—		—		17,000		(21,282		)

Schedule of Estimated Fair Values of Financial Instruments by Level of Valuation Inputs

A summary of the estimated fair values of financial instruments follows:

	`				Fair Value Measurements at Reporting Date Using
As of December 31, 2012	Carrying Amount		Estimated Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and cash equivalents	$	801,332	$	801,332	$	—	$	801,332	$	—
Investment securities available-for-sale	1,995,258		1,995,258		—		1,995,258		—
Investment securities held-to-maturity	208,223		218,933		—		218,933		—
Accrued interest receivable	28,869		28,869		—		28,869		—
Mortgage servicing rights, net	12,653		16,373		—		16,373
Net loans	4,123,401		4,142,426		—		4,067,803		74,623
Total financial assets	$	7,169,736	$	7,203,191	$	—	$	7,128,568	$	74,623
Financial liabilities:
Total deposits, excluding time deposits	$	4,854,927	$	4,854,927	$	—	$	4,854,927	$	—
Time deposits	1,385,484		1,394,403		—		1,394,403		—
Securities sold under repurchase agreements	505,785		505,785		—		505,785		—
Other borrowed funds	32		32		—		32		—
Accrued interest payable	6,502		6,502		—		6,502		—
Long-term debt	37,160		35,104		—		35,104		—
Preferred stock pending redemption	50,000		50,000		—		50,000		—
Subordinated debentures held by subsidiary trusts	82,477		62,409		—		62,409
Total financial liabilities	$	6,922,367	$	6,909,162	$	—	$	6,909,162	$	—

					Fair Value Measurements at Reporting Date Using
As of December 31, 2011	Carrying Amount		Estimated Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and cash equivalents	$	472,447	$	472,447	$	—	$	472,447	$	—
Investment securities available-for-sale	2,016,864		2,016,864		—		2,016,864		—
Investment securities held-to-maturity	152,781		161,877		—		161,877		—
Accrued interest receivable	31,974		31,974		—		31,974		—
Mortgage servicing rights, net	11,555		11,910		—		11,910		—
Net loans	4,073,968		4,064,718		—		3,964,683		100,035
Total financial assets	$	6,759,589	$	6,759,790	$	—	$	6,659,755	$	100,035
Financial liabilities:
Total deposits, excluding time deposits	$	4,269,631	$	4,269,631	$	—	$	4,269,631	$	—
Time deposits	1,557,340		1,565,558		—		1,565,558		—
Securities sold under repurchase agreements	516,243		516,243		—		516,243		—
Other borrowed funds	7		7		—		7		—
Accrued interest payable	8,123		8,123		—		8,123		—
Long-term debt	37,200		34,341		—		34,341		—
Subordinated debentures held by subsidiary trusts	123,715		102,525		—		102,525		—
Derivative contract liability	383		383				—		383
Total financial liabilities	$	6,512,642	$	6,496,811	$	—	$	6,496,428	$	383