Fair Value (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value [Abstract]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

	June 30, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	74,840	$	—	$	74,840
Municipal obligations		—		245,156		—		245,156
Corporate debt securities		—		3,500		—		3,500
Residential mortgage-backed securities		—		1,854,099		—		1,854,099
Commercial mortgage-backed securities		—		433,098		—		433,098
Collateralized mortgage obligations		—		183,689		—		183,689
Total available for sale securities		—		2,794,382		—		2,794,382
Derivative assets (1)		—		16,875		—		16,875
Total recurring fair value measurements - assets	$	—	$	2,811,257	$	—	$	2,811,257
Liabilities
Derivative liabilities (1)	$	—	$	12,213	$	—	$	12,213
Total recurring fair value measurements - liabilities	$	—	$	12,213	$	—	$	12,213

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

	December 31, 2016
(in thousands)	Level 1		Level 2		Level 3		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	54,828	$	—	$	54,828
Municipal obligations		—		242,155		—		242,155
Corporate debt securities		—		3,500		—		3,500
Residential mortgage-backed securities		—		1,611,355		—		1,611,355
Commercial mortgage-backed securities		—		402,591		—		402,591
Collateralized mortgage obligations		—		202,479		—		202,479
Total available for sale securities		—		2,516,908		—		2,516,908
Derivative assets (1)		—		20,315		—		20,315
Total recurring fair value measurements - assets	$	—	$	2,537,223	$	—	$	2,537,223
Liabilities
Derivative liabilities (1)	$	—	$	27,432	$	—	$	27,432
Total recurring fair value measurements - liabilities	$	—	$	27,432	$	—	$	27,432

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

Financial Assets Measured at Fair Value on Nonrecurring Basis

	June 30, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	137,653	$	—	$	137,653
Other real estate owned		—		—		8,447		8,447
Total nonrecurring fair value measurements	$	—	$	137,653	$	8,447	$	146,100

	December 31, 2016
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	169,888	$	—	$	169,888
Other real estate owned		—		—		13,968		13,968
Total nonrecurring fair value measurements	$	—	$	169,888	$	13,968	$	183,856

Estimated Fair Values of Financial Instruments

	June 30, 2017
							Total Fair		Carrying
(in thousands)	Level 1		Level 2		Level 3		Value		Amount
Financial assets:
Cash, interest-bearing bank deposits, and federal funds sold	$	491,653	$	—	$	—	$	491,653	$	491,653
Available for sale securities		—		2,794,382		—		2,794,382		2,794,382
Held to maturity securities		—		2,866,529		—		2,866,529		2,874,454
Loans, net		—		137,653		17,954,752		18,092,405		18,251,976
Loans held for sale		—		26,787		—		26,787		26,787
Derivative financial instruments		—		16,875		—		16,875		16,875
Financial liabilities:
Deposits	$	—	$	—	$	21,432,877	$	21,432,877	$	21,442,815
Federal funds purchased		76,798		—		—		76,798		76,798
Securities sold under  agreements to repurchase		482,109		—		—		482,109		482,109
FHLB short-term borrowings		1,252,000		—		—		1,252,000		1,252,000
Long-term debt		—		407,409		—		407,409		407,876
Derivative financial instruments		—		12,213		—		12,213		12,213

	December 31, 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	$	450,866	$	—	$	—	$	450,866	$	450,866
Available for sale securities		—		2,516,908		—		2,516,908		2,516,908
Held to maturity securities		—		2,470,117		—		2,470,117		2,500,220
Loans, net		—		169,888		16,326,961		16,496,849		16,522,733
Loans held for sale		—		34,064		—		34,064		34,064
Derivative financial instruments		—		20,315		—		20,315		20,315
Financial liabilities:
Deposits	$	—	$	—	$	19,430,939	$	19,430,939	$	19,424,266
Federal funds purchased		2,275		—		—		2,275		2,275
Securities sold under  agreements to repurchase		358,131		—		—		358,131		358,131
FHLB short-term borrowings		865,000		—		—		865,000		865,000
Long-term debt		—		435,747		—		435,747		436,280
Derivative financial instruments		—		27,432		—		27,432		27,432