Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 38,199	$ 99,736
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Investment securities available-for-sale	(15,689)	27,559
Derivative instruments	(26,232)	(196)
Defined benefit pension and other postretirement benefit plans	729	1,056
Other comprehensive (loss) income, net of tax	11,272	28,811
Comprehensive Income (Loss), Net of Tax, Attributable to Parent, Total	$ 49,471	$ 128,547

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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