Derivatives - Schedule of Notional Amounts and Estimated Fair Values (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Feb. 28, 2019
Derivatives Fair Value [Line Items]
Notional Amount	$ 2,517,457	$ 6,339,935
Fair Value, Other Assets	66,333	257,137
Fair Value, Other Liabilities	19,543	11,211
Cash Flow Hedges
Derivatives Fair Value [Line Items]
Notional Amount			$ 4,000,000
Derivatives Designated as Hedging Instruments \| Cash Flow Hedges
Derivatives Fair Value [Line Items]
Notional Amount	350,000	4,350,000
Fair Value, Other Assets	23,497	239,213
Fair Value, Other Liabilities		643
Derivatives Designated as Hedging Instruments \| Cash Flow Hedges \| Commercial Loans \| Interest Rate Swaps
Derivatives Fair Value [Line Items]
Notional Amount	350,000	350,000
Fair Value, Other Assets	23,497
Fair Value, Other Liabilities		643
Derivatives Designated as Hedging Instruments \| Cash Flow Hedges \| Commercial Loans \| Interest Rate Collars
Derivatives Fair Value [Line Items]
Notional Amount		4,000,000
Fair Value, Other Assets		239,213
Derivatives Not Designated as Hedging Instruments
Derivatives Fair Value [Line Items]
Notional Amount	2,167,457	1,989,935
Fair Value, Other Assets	42,836	17,924
Fair Value, Other Liabilities	19,543	10,568
Derivatives Not Designated as Hedging Instruments \| Mortgage Loan Held for Sale Interest Rate Lock Commitments
Derivatives Fair Value [Line Items]
Notional Amount	21,350	4,138
Fair Value, Other Assets	333	22
Derivatives Not Designated as Hedging Instruments \| Mortgage Loan Held for Sale Floating Commitments
Derivatives Fair Value [Line Items]
Notional Amount	7,732	1,523
Derivatives Not Designated as Hedging Instruments \| Foreign Exchange Contracts
Derivatives Fair Value [Line Items]
Notional Amount	73,937	74,322
Fair Value, Other Assets	1,614	379
Fair Value, Other Liabilities	1,208	558
Derivatives Not Designated as Hedging Instruments \| Commercial Loans \| Interest Rate Swaps
Derivatives Fair Value [Line Items]
Notional Amount	1,203,681	1,008,805
Fair Value, Other Assets	24,533	8,386
Fair Value, Other Liabilities	1,956	899
Derivatives Not Designated as Hedging Instruments \| Commercial Loans \| Interest Rate Collars
Derivatives Fair Value [Line Items]
Notional Amount	73,332	75,555
Fair Value, Other Assets	711	257
Fair Value, Other Liabilities	711	257
Derivatives Not Designated as Hedging Instruments \| Commercial Loans \| Interest Rate Caps
Derivatives Fair Value [Line Items]
Notional Amount	171,470	167,185
Fair Value, Other Assets	11	18
Fair Value, Other Liabilities	11	18
Derivatives Not Designated as Hedging Instruments \| Commercial Loans \| Interest Rate Floors
Derivatives Fair Value [Line Items]
Notional Amount	613,250	654,298
Fair Value, Other Assets	15,634	8,836
Fair Value, Other Liabilities	15,634	8,836
Derivatives Not Designated as Hedging Instruments \| Forward Contracts \| Mortgage Loan Forward Sale Commitments
Derivatives Fair Value [Line Items]
Notional Amount	2,705	4,109
Fair Value, Other Assets		$ 26
Fair Value, Other Liabilities	$ 23

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Nominal or face amount used to calculate payment on derivative.

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