Fair Value (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value [Abstract]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

	September 30, 2016
(in thousands)	Level 1		Level 2		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	20,671	$	20,671
Municipal obligations		—		217,018		217,018
Corporate debt securities		—		3,500		3,500
Residential mortgage-backed securities		—		1,775,925		1,775,925
Commercial mortgage-backed securities		—		173,109		173,109
Collateralized mortgage obligations		—		223,256		223,256
Equity securities		1,201		—		1,201
Total available for sale securities		1,201		2,413,479		2,414,680
Derivative assets (1)		—		36,554		36,554
Total recurring fair value measurements - assets	$	1,201	$	2,450,033	$	2,451,234
Liabilities
Derivative liabilities (1)	$	—	$	37,899	$	37,899
Total recurring fair value measurements - liabilities	$	—	$	37,899	$	37,899

(1) For further disaggregation of derivative assets and liabilities, see Note 6 - Derivatives.

	December 31, 2015
(in thousands)	Level 1		Level 2		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	134	$	134
Municipal obligations		—		39,607		39,607
Corporate debt securities		—		3,500		3,500
Residential mortgage-backed securities		—		1,758,373		1,758,373
Collateralized mortgage obligations		—		289,033		289,033
Equity securities		2,757		—		2,757
Total available for sale securities		2,757		2,090,647		2,093,404
Derivative assets (1)		—		23,251		23,251
Total recurring fair value measurements - assets	$	2,757	$	2,113,898	$	2,116,655
Liabilities
Derivative liabilities (1)	$	—	$	23,968	$	23,968
Total recurring fair value measurements - liabilities	$	—	$	23,968	$	23,968

(1) For further disaggregation of derivative assets and liabilities, see Note 6 - Derivatives.

Financial Assets Measured at Fair Value on Nonrecurring Basis

	September 30, 2016
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	126,401	$	—	$	126,401
Other real estate owned		—		—		14,626		14,626
Total nonrecurring fair value measurements	$	—	$	126,401	$	14,626	$	141,027

	December 31, 2015
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	93,602	$	—	$	93,602
Other real estate owned		—		—		17,206		17,206
Total nonrecurring fair value measurements	$	—	$	93,602	$	17,206	$	110,808

Estimated Fair Values of Financial Instruments

	September 30, 2016
							Total Fair		Carrying
(in thousands)	Level 1		Level 2		Level 3		Value		Amount
Financial assets:
Cash, interest-bearing bank deposits, and federal funds sold	$	458,792	$	—	$	—	$	458,792	$	458,792
Available for sale securities		1,201		2,413,479		—		2,414,680		2,414,680
Held to maturity securities		—		2,482,540		—		2,482,540		2,428,432
Loans, net		—		126,401		15,926,313		16,052,714		15,834,760
Loans held for sale		—		42,545		—		42,545		42,545
Derivative financial instruments		—		36,554		—		36,554		36,554
Financial liabilities:
Deposits	$	—	$	—	$	18,885,148	$	18,885,148	$	18,885,477
Federal funds purchased		1,250		—		—		1,250		1,250
Securities sold under  agreements to repurchase		335,894		—		—		335,894		335,894
FHLB borrowings		738,812		—		—		738,812		738,812
Long-term debt		—		468,091		—		468,091		463,710
Derivative financial instruments		—		37,899		—		37,899		37,899

	December 31, 2015
							Total Fair		Carrying
(in thousands)	Level 1		Level 2		Level 3		Value		Amount
Financial assets:
Cash, interest-bearing bank deposits, and federal funds sold	$	869,429	$	—	$	—	$	869,429	$	869,429
Available for sale securities		2,757		2,090,647		—		2,093,404		2,093,404
Held to maturity securities		—		2,375,851		—		2,375,851		2,370,388
Loans, net		—		93,602		15,334,201		15,427,803		15,522,135
Loans held for sale		—		20,434		—		20,434		20,434
Derivative financial instruments		—		23,251		—		23,251		23,251
Financial liabilities:
Deposits	$	—	$	—	$	18,327,425	$	18,327,425	$	18,348,912
Federal funds purchased		10,100		—		—		10,100		10,100
Securities sold under  agreements to repurchase		513,544		—		—		513,544		513,544
FHLB borrowings		900,000		—		—		900,000		900,000
Long-term debt		—		488,711		—		488,711		490,145
Derivative financial instruments		—		23,968		—		23,968		23,968