Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value of Financial Instruments [Abstract]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

	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 10 – 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 10 – Derivatives.

Financial Assets Measured at Fair Value on Nonrecurring Basis

	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

	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

	December 31, 2017
							Total		Carrying
(in thousands)	Level 1		Level 2		Level 3		Fair 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
Short-term FHLB 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

	December 31, 2016
							Total		Carrying
(in thousands)	Level 1		Level 2		Level 3		Fair 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 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