Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2013

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, 2013	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	$	763,238	$	—	$	763,238	$	—
U.S. agency mortgage-backed securities & collateralized mortgage obligations	1,184,053		—		1,184,053		—
Private mortgage-backed securities	415		—		415		—
Mortgage servicing rights	25,698		—		25,698		—

			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. agency 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		—

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
As of December 31, 2013	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs  (Level 2)		Significant Unobservable Inputs (Level 3)		Total Gains (Losses)
Impaired loans	$	57,302	$	—	$	—	$	57,302	$	(23,224	)
Other real estate owned	8,502		—		—		8,502		(14,441		)
Long-lived assets to be disposed of by sale	1,186		—		—		1,186		(599		)

			Fair Value Measurements at Reporting Date Using
As of December 31, 2012	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Gains (Losses)
Impaired loans	$	74,623	$	—	$	—	$	74,623	$	(32,624	)
Other real estate owned	15,745		—		—		15,745		(20,797		)
Long-lived assets to be disposed of by sale	496		—		—		496		(70		)

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, 2013	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	$	534,827	$	534,827	$	—	$	534,827	$	—
Investment securities available-for-sale	1,947,706		1,947,706		—		1,947,706		—
Investment securities held-to-maturity	203,837		205,926		—		205,926		—
Accrued interest receivable	26,450		26,450		—		26,450		—
Mortgage servicing rights, net	13,546		25,698		—		25,698		—
Net loans	4,259,514		4,246,539		—		4,189,237		57,302
Total financial assets	$	6,985,880	$	6,987,146	$	—	$	6,929,844	$	57,302
Financial liabilities:
Total deposits, excluding time deposits	$	4,943,033	$	4,943,033	$	—	$	4,943,033	$	—
Time deposits	1,190,717		1,196,250		—		1,196,250		—
Securities sold under repurchase agreements	457,437		457,437		—		457,437		—
Other borrowed funds	3		3		—		3		—
Accrued interest payable	4,963		4,963		—		4,963		—
Long-term debt	36,917		34,508		—		34,508		—
Subordinated debentures held by subsidiary trusts	82,477		72,045		—		72,045		—
Total financial liabilities	$	6,715,547	$	6,708,239	$	—	$	6,708,239	$	—

					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	$	—