Components of Other Comprehensive Income/(Loss) - Schedule of Reclassification from AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Debt securities gains/(losses), net	$ 0	$ 52
Provision/(benefit) for income taxes	27,058	29,931
Amounts reclassified from AOCI	2,914	1,093
Interest and fees on loans	331,938	299,493
All other expense (Note 8)	19,786	35,332
Securities AFS
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	0	(39)
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	1,451	(155)
Pension and Post-retirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	1,463	1,287
Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	2,914	1,093
Reclassification out of Accumulated Other Comprehensive Income \| Securities AFS
Accumulated Other Comprehensive Income (Loss) [Line Items]
Debt securities gains/(losses), net	0	(52)
Provision/(benefit) for income taxes	0	13
Amounts reclassified from AOCI	0	(39)
Reclassification out of Accumulated Other Comprehensive Income \| Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Provision/(benefit) for income taxes	(476)	51
Amounts reclassified from AOCI	1,451	(155)
Interest and fees on loans	1,927	(206)
Reclassification out of Accumulated Other Comprehensive Income \| Pension and Post-retirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	1,463	1,287
All other expense (Note 8)	1,943	1,709
Reclassification from AOCI, current period, tax	$ (480)	$ (422)

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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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