Commitments and Contingencies (Off-Balance Sheet Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Commitments to Extend Credit [Member]
Loss Contingencies [Line Items]
Contract amounts	$ 7,591,029	$ 7,530,143
Letters of Credit [Member]
Loss Contingencies [Line Items]
Contract amounts	$ 366,112	$ 393,284

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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