Commitments and Contingencies (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Guarantor Obligations [Line Items]
Amortization Method Qualified Affordable Housing Project Investments	$ 167,800	$ 147,300
FDIC shared-loss payable	112,395	105,618	$ 101,342
Commitments to Extend Credit
Guarantor Obligations [Line Items]
Unused Commitments to Extend Credit	10,682,378	10,054,712
Amortization Method Qualified Affordable Housing Project Investments	70,000	68,000
Standby Letters of Credit
Guarantor Obligations [Line Items]
Affordable Housing Program Obligation	$ 99,601	$ 96,467