Parent Company Financial Information (Condensed Statements of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Activities
Net income	$ 250,178	$ 202,820	$ 154,244
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation expense	16,158	14,926	10,737
Net cash provided by operating activities	300,684	235,065	192,292
Cash Flows From Investing Activities
Net cash received in business combinations	0	154,984	0
Net cash used in investing activities	(395,690)	(2,358,360)	(1,918,785)
Financing Activities
Cash dividends paid	(94,314)	(83,790)	(95,509)
Repayments of Junior Subordinated Debt	0	35,000	0
Purchase and retirement of common stock	3,989	4,140	2,522
Purchase of treasury stock	0	0	(20,000)
Proceeds from exercise of stock options and employee stock purchase plan	2,110	2,350	2,028
Net cash provided by financing activities	(437,967)	2,294,243	2,132,586
Supplemental Information:
Stock Issued	0	256,061	0
Cash and cash equivalents at beginning of period	824,714
Cash and cash equivalents at end of period	291,741	824,714
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(532,973)	170,948	406,093
Parent Company
Operating Activities
Net income	250,178	202,820	154,244
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings of subsidiaries	(172,693)	(99,321)	(68,826)
Stock-based compensation expense	16,158	14,926	10,737
Net changes in other assets and liabilities	5,379	(1,436)	(17)
Net cash provided by operating activities	99,022	116,989	96,138
Cash Flows From Investing Activities
Net cash received in business combinations	0	2,173	0
Net cash used in investing activities	0	2,173	0
Financing Activities
Cash dividends paid	(94,394)	(83,841)	(96,215)
Repayments of Junior Subordinated Debt	0	35,000	0
Purchase and retirement of common stock	3,989	4,140	2,522
Purchase of treasury stock	0	0	(20,000)
Proceeds from exercise of stock options and employee stock purchase plan	2,110	2,350	2,028
Net cash provided by financing activities	(96,273)	(120,631)	(116,709)
Supplemental Information:
Stock Issued	0	256,061	0
Cash and cash equivalents at beginning of period	5,765	7,234	27,805
Cash and cash equivalents at end of period	8,514	5,765	7,234
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	$ 2,749	$ (1,469)	$ (20,571)