Condensed Financial Information - Parent Company Only Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
ASSETS
Other assets	$ 1,004,397	$ 1,078,128
Investments in:
Total Assets	25,796,398	25,906,733
Other liabilities	465,110	514,004
Total Liabilities	23,083,718	23,289,905
Shareholders' Equity [Abstract]
Shareholders’ equity	2,712,680	2,616,828	$ 2,342,176	$ 2,247,573
Total Liabilities and Shareholders’ Equity	25,796,398	25,906,733
Parent
ASSETS
Cash and cash equivalents	352,715	10,063	$ 10,841	$ 30,941
Other assets	25,888	28,940
Receivable from subsidiaries	50,822	53,438
Investments in:
Bank subsidiary	2,872,274	3,045,529
Non-bank subsidiaries	188,171	313,003
Total Assets	3,489,870	3,450,973
Long-term borrowings	620,406	759,782
Payable to non-bank subsidiaries	78,793	0
Other liabilities	77,991	74,363
Total Liabilities	777,190	834,145
Shareholders' Equity [Abstract]
Shareholders’ equity	2,712,680	2,616,828
Total Liabilities and Shareholders’ Equity	$ 3,489,870	$ 3,450,973