Condensed Parent Company Financial Statements (Statements of Financial Condition) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash	$ 286,167	$ 392,142
Loans, net of unearned income	26,800,290	23,820,691
Allowance for loan losses	(156,828)	(152,770)	$ (137,905)
Net loans	26,643,462	23,667,921
Goodwill	645,220	573,141
Total assets	36,620,583	31,244,849	27,915,970
Liabilities and Shareholders’ Equity
Subordinated notes	436,095	139,210
Other borrowings	418,174	393,855
Junior subordinated debentures	253,566	253,566
Shareholders’ equity	3,691,250	3,267,570	$ 2,976,939	$ 2,695,617
Total liabilities and shareholders’ equity	36,620,583	31,244,849
Reportable Legal Entities | Parent Company
Assets
Cash	96,245	37,931
Available-for-sale debt securities and equity securities with readily determinable fair value	14,695	12,765
Investment in and receivable from subsidiaries	4,266,278	3,660,968
Loans, net of unearned income	75	1,200
Allowance for loan losses	(5)	0
Net loans	70	1,200
Goodwill	8,371	8,371
Other assets	353,064	206,902
Total assets	4,738,723	3,928,137
Liabilities and Shareholders’ Equity
Other liabilities	188,275	75,609
Subordinated notes	436,095	139,210
Other borrowings	169,537	192,182
Junior subordinated debentures	253,566	253,566
Shareholders’ equity	3,691,250	3,267,570
Total liabilities and shareholders’ equity	$ 4,738,723	$ 3,928,137