Additional Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Other Significant Noncash Transactions [Line Items]
Interest paid	$ 59,535	$ 95,040
Income taxes (refunded) paid	46,693	30,708
Transfers of premises to premises held for sale	0	1,072
Transfers of other real estate owned to premises held for sale	0	3,504
Transfers of premises held for sale to other real estate owned	4,368	0
Transfers of premises held for sale to premises	5,610	0
Transfers of loans to other assets held for sale	0	114,925
Transfers of deposits to other liabilities held for sale	0	58,405
Transfers of loans to foreclosed assets held for sale
Other Significant Noncash Transactions [Line Items]
Transfers of loans and premises	3,516	3,083
Transfers of premises to foreclosed assets and other real estate owned
Other Significant Noncash Transactions [Line Items]
Transfers of loans and premises	$ 0	$ 3,120

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