Additional Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Other Significant Noncash Transactions [Line Items]
Interest paid	$ 95,040	$ 130,904
Income taxes paid	30,708	34,028
Transfers of premises to premises held for sale	1,072	0
Transfers of other real estate owned to premises held for sale	3,504	0
Right-of-use lease assets obtained in exchange for lessee operating lease liabilities (adoption of ASU 2016-02)	0	32,757
Transfers of loans to other assets held for sale	114,925	0
Transfers of deposits to other liabilities held for sale	58,405	0
Transfers of loans to foreclosed assets held for sale
Other Significant Noncash Transactions [Line Items]
Transfers of loans and premises	3,083	3,666
Transfers of premises to foreclosed assets and other real estate owned
Other Significant Noncash Transactions [Line Items]
Transfers of loans and premises	$ 3,120	$ 556

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