Components of Other Comprehensive Income/(loss) (Schedule of Reclassification from AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Debt securities gains/(losses), net	$ 52	$ 44
Provision/(benefit) for income taxes	29,931	27,054
Amounts reclassified from AOCI	1,093	294
Interest and fees on loans	299,493	180,464
Securities AFS
Accumulated Other Comprehensive Income (Loss) [Line Items]
Debt securities gains/(losses), net	(52)	(44)
Provision/(benefit) for income taxes	13	17
Amounts reclassified from AOCI	(39)	(27)
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Provision/(benefit) for income taxes	51	528
Amounts reclassified from AOCI	(155)	(852)
Interest and fees on loans	(206)	(1,380)
Pension and Post-retirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	1,287	1,173
All other expense	1,709	1,900
Reclassification from AOCI, current period, tax	$ (422)	$ (727)

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

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