Additional Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Other Significant Noncash Transactions [Line Items]
Interest paid	$ 39,388	$ 38,047
Income taxes paid (refunded)	92	(54)
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	508	569
Transfers of premises to foreclosed assets and other real estate owned
Other Significant Noncash Transactions [Line Items]
Transfers of loans	$ 3,120	$ 0

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