Derivative Financial Instruments - Impact of Derivatives on Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash Flow Hedges
Interest expense	$ 174,817	$ 164,172
Trading
Total	46,342	1,573
Designated as Hedging Instrument
Fair Value Hedges
Interest recognized on derivatives	4,623	(3,827)
Hedged items recorded in interest expense	(143,248)	(23,986)
Derivatives recorded in interest expense	144,183	23,888
Trading
Total	5,558	(3,925)
Designated as Hedging Instrument \| Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent \| Reclassification out of Accumulated Other Comprehensive Income
Cash Flow Hedges
Interest expense	(1,528)	1,296
Trading
Trading
Change in fair value of future interest payments recorded in earnings	42,312	4,202
Total	$ 42,312	$ 4,202

Derivative Instruments Increase (Decrease) In Fair Value Of Future Interest Payments Recorded In Earnings

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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Amount of the cost of borrowed funds accounted for as interest expense.

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