Components of Other Comprehensive Income/(loss) - Schedule of Reclassification from AOCI (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and fees on loans	$ 305,913	$ 352,112	$ 632,512	$ 684,050
Provision/(benefit) for income taxes	12,780	34,467	17,547	61,525
Amounts reclassified from AOCI	756	3,096	2,767	6,010
All other expense	35,751	28,681	68,977	48,012
Securities AFS
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	0	201	0	201
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	(1,623)	1,334	(1,717)	2,785
Pension and Post-retirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	2,379	1,561	4,484	3,024
Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	756	3,096	2,767	6,010
Reclassification out of Accumulated Other Comprehensive Income \| Securities AFS
Accumulated Other Comprehensive Income (Loss) [Line Items]
Debt securities gains/(losses), net	0	267	0	267
Provision/(benefit) for income taxes	0	(66)	0	(66)
Amounts reclassified from AOCI	0	201	0	201
Reclassification out of Accumulated Other Comprehensive Income \| Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and fees on loans	(2,153)	1,772	(2,277)	3,699
Provision/(benefit) for income taxes	530	(438)	560	(914)
Amounts reclassified from AOCI	(1,623)	1,334	(1,717)	2,785
Reclassification out of Accumulated Other Comprehensive Income \| Pension and Post-retirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	2,379	1,561	4,484	3,024
All other expense	3,155	2,074	5,946	4,017
Reclassification from AOCI, current period, tax	$ (776)	$ (513)	$ (1,462)	$ (993)

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Interest and fee income generated by loans the Entity intends and has the ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (1) industrial and agricultural; (2) real estate; and (3) real estate construction loans; (4) trade financing; (5) lease financing; (6) home equity lines-of-credit; (7) automobile and other vehicle loans; and (8) credit card and other revolving-type loans. Also includes interest income for leases held by the Entity.

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