Additional Cash Flow Information - Additional Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Other Significant Noncash Transactions [Line Items]
Interest paid	$ 82,914	$ 123,995	$ 182,541
Income taxes paid	55,202	47,777	51,999
Transfers of premises to premises held for sale	0	11,200	0
Transfers of other real estate owned to premises held for sale	0	4,163	0
Transfer of premises held for sale to other real estate owned	4,368	0	0
Transfer of premises held for sale to premises	5,610	0	0
Right-of-use lease assets obtained in exchange for lessee operating lease liabilities (adoption of ASU 2016-02)	0	0	32,757
Transfers of available-for-sale to held-to-maturity securities	500,809	0	0
Transfers of held-to-maturity to available-for-sale securities	0	0	216,373
Transfers of loans to other assets held for sale	0	114,925	259,939
Transfers of deposits to other liabilities held for sale	0	213,025	159,853
Transfers of loans to foreclosed assets held for sale
Other Significant Noncash Transactions [Line Items]
Real estate transferred	4,322	10,712	4,760
Transfers of premises to foreclosed assets and other real estate owned
Other Significant Noncash Transactions [Line Items]
Real estate transferred	$ 0	$ 3,120	$ 647

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