Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2018

Fair Value Measurements [Abstract]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

	March 31, 2018
(in thousands)	Level 1		Level 2		Level 3		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	93,884	$	—	$	93,884
Municipal obligations		—		237,291		—		237,291
Corporate debt securities		—		5,500		—		5,500
Residential mortgage-backed securities		—		1,743,543		—		1,743,543
Commercial mortgage-backed securities		—		680,272		—		680,272
Collateralized mortgage obligations		—		155,158		—		155,158
Total available for sale securities		—		2,915,648		—		2,915,648
Derivative assets (1)		—		12,682		—		12,682
Total recurring fair value measurements - assets	$	—	$	2,928,330	$	—	$	2,928,330
Liabilities
Derivative liabilities (1)	$	—	$	22,529	$	—	$	22,529
Total recurring fair value measurements - liabilities	$	—	$	22,529	$	—	$	22,529

	December 31, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	97,272	$	—	$	97,272
Municipal obligations		—		243,786		—		243,786
Corporate debt securities		—		3,500		—		3,500
Residential mortgage-backed securities		—		1,715,213		—		1,715,213
Commercial mortgage-backed securities		—		687,135		—		687,135
Collateralized mortgage obligations		—		163,963		—		163,963
Total available for sale securities		—		2,910,869		—		2,910,869
Derivative assets (1)		—		14,157		—		14,157
Total recurring fair value measurements - assets	$	—	$	2,925,026	$	—	$	2,925,026
Liabilities
Derivative liabilities (1)	$	—	$	14,389	$	—	$	14,389
Total recurring fair value measurements - liabilities	$	—	$	14,389	$	—	$	14,389

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

Financial Assets Measured at Fair Value on Nonrecurring Basis

	March 31, 2018
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	205,945	$	—	$	205,945
Other real estate owned		—		—		5,493		5,493
Total nonrecurring fair value measurements	$	—	$	205,945	$	5,493	$	211,438

	December 31, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	184,205	$	—	$	184,205
Other real estate owned		—		—		6,928		6,928
Total nonrecurring fair value measurements	$	—	$	184,205	$	6,928	$	191,133

Estimated Fair Values of Financial Instruments

	March 31, 2018
							Total Fair		Carrying
(in thousands)	Level 1		Level 2		Level 3		Value		Amount
Financial assets:
Cash, interest-bearing bank deposits, and federal funds sold	$	315,401	$	—	$	—	$	315,401	$	315,401
Available for sale securities		—		2,915,648		—		2,915,648		2,915,648
Held to maturity securities		—		2,952,295		—		2,952,295		3,014,428
Loans, net		—		205,945		18,337,770		18,543,715		18,881,791
Loans held for sale		—		21,827		—		21,827		21,827
Derivative financial instruments		—		12,682		—		12,682		12,682
Financial liabilities:
Deposits	$	—	$	—	$	22,438,772	$	22,438,772	$	22,485,722
Federal funds purchased		25,967		—		—		25,967		25,967
Securities sold under  agreements to repurchase		443,151		—		—		443,151		443,151
FHLB short-term borrowings		982,979		—		—		982,979		982,979
Long-term debt		—		297,555		—		297,555		300,443
Derivative financial instruments		—		22,529		—		22,529		22,529

	December 31, 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	$	479,332	$	—	$	—	$	479,332	$	479,332
Available for sale securities		—		2,910,869		—		2,910,869		2,910,869
Held to maturity securities		—		2,962,010		—		2,962,010		2,977,511
Loans, net		—		184,205		18,403,303		18,587,508		18,786,855
Loans held for sale		—		39,865		—		39,865		39,865
Derivative financial instruments		—		14,157		—		14,157		14,157
Financial liabilities:
Deposits	$	—	$	—	$	22,238,847	$	22,238,847	$	22,253,202
Federal funds purchased		140,754		—		—		140,754		140,754
Securities sold under  agreements to repurchase		430,569		—		—		430,569		430,569
FHLB short-term borrowings		1,132,567		—		—		1,132,567		1,132,567
Long-term debt		—		303,631		—		303,631		305,513
Derivative financial instruments		—		14,389		—		14,389		14,389