Commitments and Contingencies (Off-Balance Sheet Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Commitments to Extend Credit [Member]
Loss Contingencies [Line Items]
Contract amounts	$ 7,478,907	$ 7,234,528
Letters of Credit [Member]
Loss Contingencies [Line Items]
Contract amounts	$ 389,998	$ 365,498

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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