Condensed Parent Company Financial Statements (Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Activities:
Net income	$ 509,682	$ 466,151	$ 292,990
Adjustments to reconcile net income to net cash provided by operating activities
Losses (gains) on available-for-sale debt securities and equity securities with readily determinable fair value, net	20,427	1,059	2,373
Depreciation and amortization	82,070	101,797	96,369
Deferred income tax (benefit) expense	22,057	(2,861)	(4,058)
Stock-based compensation expense	31,748	16,177	(4,938)
(Increase) decrease in other assets	(91,585)	187,743	(131,870)
(Decrease) increase in other liabilities	377,396	78,475	46,924
Net Cash Provided by (Used for) Operating Activities	1,375,000	1,130,872	(518,465)
Investing Activities:
Net Cash Used for Investing Activities	(3,490,769)	(5,928,859)	(7,182,424)
Financing Activities:
Increase (decrease) in subordinated notes, other borrowings and junior subordinated debentures, net	125,135	(27,784)	88,596
Proceeds from the issuance of common stock, net	285,729	0	0
Proceeds from the issuance of preferred stock, net	0	0	277,613
Issuance of common shares resulting from exercise of stock options and employee stock purchase plan	11,233	19,824	15,059
Dividends paid	(108,210)	(98,629)	(85,890)
Common stock repurchases under authorized program	0	(9,540)	(92,055)
Common stock repurchases for tax withholdings related to stock-based compensation	(304)	0	(1,377)
Net Cash Provided by Financing Activities	2,195,530	4,886,718	7,736,887
Net Increase in Cash and Cash Equivalents	79,761	88,731	35,998
Cash and Cash Equivalents at Beginning of Period	411,205	322,474	286,476
Cash and Cash Equivalents at End of Period	490,966	411,205	322,474
Reportable Legal Entities | Parent Company
Operating Activities:
Net income	509,682	466,151	292,990
Adjustments to reconcile net income to net cash provided by operating activities
Losses (gains) on available-for-sale debt securities and equity securities with readily determinable fair value, net	7,018	(1,794)	(192)
Depreciation and amortization	27,642	28,783	22,224
Deferred income tax (benefit) expense	(2,773)	(5,350)	11,336
Stock-based compensation expense	13,632	6,769	(2,813)
(Increase) decrease in other assets	(7,116)	6,598	4,838
(Decrease) increase in other liabilities	(6,107)	1,225	2,388
Equity in undistributed net income of subsidiaries	(662,742)	(482,336)	(162,942)
Net Cash Provided by (Used for) Operating Activities	(120,764)	20,046	167,829
Investing Activities:
Capital contributions to subsidiaries, net	(69,000)	(27,000)	(12,000)
Other investing activity, net	(30,872)	(22,877)	(40,127)
Net Cash Used for Investing Activities	(99,872)	(49,877)	(52,127)
Financing Activities:
Increase (decrease) in subordinated notes, other borrowings and junior subordinated debentures, net	117,381	(23,274)	(2,690)
Proceeds from the issuance of common stock, net	285,729	0	0
Proceeds from the issuance of preferred stock, net	0	0	277,613
Issuance of common shares resulting from exercise of stock options and employee stock purchase plan	11,233	19,824	15,059
Dividends paid	(108,210)	(98,629)	(85,890)
Common stock repurchases under authorized program	0	(9,540)	(92,055)
Common stock repurchases for tax withholdings related to stock-based compensation	(304)	0	(1,377)
Net Cash Provided by Financing Activities	305,829	(111,619)	110,660
Net Increase in Cash and Cash Equivalents	85,193	(141,450)	226,362
Cash and Cash Equivalents at Beginning of Period	181,157	322,607	96,245
Cash and Cash Equivalents at End of Period	$ 266,350	$ 181,157	$ 322,607