Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2014

Fair Value Disclosures [Abstract]

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

The following table summarizes financial assets and financial liabilities measured at fair value on a recurring basis as of December 31, 2014 and 2013, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value:

	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
2014
Securities available for sale:
U.S. Treasury	$	3,811,252	$	—	$	—	$	3,811,252
Residential mortgage-backed securities	—		1,398,724		—		1,398,724
States and political subdivisions	—		3,208,907		—		3,208,907
Other	—		42,371		—		42,371
Trading account securities:
U.S. Treasury	15,339		—		—		15,339
States and political subdivisions	—		87		—		87
Derivative assets:
Interest rate swaps, caps and floors	—		40,931		170		41,101
Commodity swaps and options	—		32,829		—		32,829
Foreign currency forward contracts	666		—		—		666
Derivative liabilities:
Interest rate swaps, caps and floors	—		43,853		—		43,853
Commodity swaps and options	—		32,729		—		32,729
Foreign currency forward contracts	617		—		—		617
2013
Securities available for sale:
U.S. Treasury	$	2,540,554	$	—	$	—	$	2,540,554
U.S. government agencies/corporations	—		53,980		—		53,980
Residential mortgage-backed securities	—		1,776,016		—		1,776,016
States and political subdivisions	—		1,488,914		—		1,488,914
Other	—		35,972		—		35,972
Trading account securities:
U.S. Treasury	15,389		—		—		15,389
States and political subdivisions	—		1,009		—		1,009
Derivative assets:
Interest rate swaps, caps and floors	—		44,520		174		44,694
Commodity swaps and options	—		10,026		—		10,026
Foreign currency forward contracts	135		—		—		135
Derivative liabilities:
Interest rate swaps, caps and floors	—		47,542		—		47,542
Commodity swaps and options	—		9,712		—		9,712
Foreign currency forward contracts	85		—		—		85

Impaired Loans Remeasured and Reported at Fair Value of Underlying Collateral

The following table presents impaired loans that were remeasured and reported at fair value through a specific valuation allowance allocation of the allowance for loan losses based upon the fair value of the underlying collateral:

	2014					2013					2012
	Level 2		Level 3			Level 2			Level 3		Level 2			Level 3
Carrying value of impaired loans before allocations	$	—	$	2,715		$	9,374		$	—	$	18,319		$	15,754
Specific valuation allowance allocations	—		(1,475		)	(2,785		)	—		(3,634		)	(2,911		)
Fair value	$	—	$	1,240		$	6,589		$	—	$	14,685		$	12,843

Foreclosed Assets Remeasured and Reported at Fair Value

The following table presents foreclosed assets that were remeasured and reported at fair value:

	2014			2013			2012
Foreclosed assets remeasured at initial recognition:
Carrying value of foreclosed assets prior to remeasurement	$	6,388		$	7,580		$	9,428
Charge-offs recognized in the allowance for loan losses	(285		)	(710		)	(1,611		)
Fair value	$	6,103		$	6,870		$	7,817
Foreclosed assets remeasured subsequent to initial recognition:
Carrying value of foreclosed assets prior to remeasurement	$	5,026		$	4,979		$	12,126
Write-downs included in other non-interest expense	(1,289		)	(895		)	(2,093		)
Fair value	$	3,737		$	4,084		$	10,033

Estimated Fair Values of Financial Instruments

The estimated fair values of financial instruments that are reported at amortized cost in the Corporation’s consolidated balance sheets, segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value, were as follows:

	December 31, 2014				December 31, 2013
	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Financial assets:
Level 2 inputs:
Cash and cash equivalents	$	4,364,123	$	4,364,123	$	4,556,125	$	4,556,125
Securities held to maturity	2,926,486		2,966,390		3,139,748		3,029,663
Cash surrender value of life insurance policies	172,050		172,050		141,108		141,108
Accrued interest receivable	128,436		128,436		99,281		99,281
Level 3 inputs:
Loans, net	10,887,993		10,939,684		9,423,262		9,582,734
Financial liabilities:
Level 2 inputs:
Deposits	24,135,930		24,136,402		20,688,786		20,689,323
Federal funds purchased and repurchase agreements	803,119		803,119		668,253		668,253
Junior subordinated deferrable interest debentures	137,115		137,115		123,712		123,712
Subordinated notes payable and other borrowings	100,000		95,591		100,000		92,552
Accrued interest payable	1,132		1,132		1,300		1,300