Segment Information (Summary Of Financial Information By Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended							9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Net interest income	$ 287,604				$ 235,074			$ 764,537	$ 686,268
Provision (recapture) for credit losses	27,572				(18,919)			51,068	(41,915)
Origination and sale	10,515				30,293			42,460	134,165
Servicing	9,529				9,172			28,174	27,379
Changes due to collection/realization of expected cash flows over time	(4,978)				(4,681)			(15,286)	(13,592)
Changes due to valuation inputs or assumptions	16,403				(634)			67,451	(4,326)
MSR hedge loss	(14,128)				0			(14,128)	0
Gain on sale of debt securities, net	0				0			2	4
Loss on equity securities, net	(2,647)				(343)			(7,383)	(1,045)
Gain on swap derivatives, net	4,194				1,429			18,578	8,698
Change in fair value of certain loans held for investment	(26,397)				3,432			(62,656)	5,704
Non-interest income (excluding above items)	36,954				35,037			107,437	116,593
Noninterest Income	29,445				73,705			164,649	273,580
Merger related expenses	769				0			5,719	0
Exit and disposal costs	1,364				3,813			4,839	9,741
Non-interest expense (excluding above items)	175,831				179,940			529,410	551,004
Allocated expenses, net	0				0			0	0
Total non-interest expense	177,964				183,753			539,968	560,745
Income before provision for income taxes	111,513				143,945			338,150	441,018
Provision for income taxes	27,473				35,879			84,362	109,072
Net income	84,040	$ 78,591	$ 91,157	$ 88,354	108,066	$ 116,143	$ 107,737	253,788	331,946
Total assets	31,471,960			30,640,936				31,471,960
Loans held for sale	148,275			353,105				148,275
Total loans and leases	25,507,951			22,553,180				25,507,951
Total deposits	26,817,107			26,594,685				26,817,107
Core Banking
Segment Reporting Information [Line Items]
Net interest income	286,532				232,348			760,628	676,837
Provision (recapture) for credit losses	27,572				(18,919)			51,068	(41,915)
Origination and sale	0				0			0	0
Servicing	0				0			0	0
Changes due to collection/realization of expected cash flows over time	0				0			0	0
Changes due to valuation inputs or assumptions	0				0			0	0
MSR hedge loss	0				0			0	0
Gain on sale of debt securities, net								2	4
Loss on equity securities, net	(2,647)				(343)			(7,383)	(1,045)
Gain on swap derivatives, net	4,194				1,429			18,578	8,698
Change in fair value of certain loans held for investment	(26,397)				3,432			(62,656)	5,704
Non-interest income (excluding above items)	36,769				34,849			106,880	115,913
Noninterest Income	11,919				39,367			55,421	129,274
Merger related expenses	769				0			5,719	0
Exit and disposal costs	1,364				3,813			4,839	9,741
Non-interest expense (excluding above items)	154,320				146,931			451,689	438,969
Allocated expenses, net	(39)				3,680			7,398	3,860
Total non-interest expense	156,414				154,424			469,645	452,570
Income before provision for income taxes	114,465				136,210			295,336	395,456
Provision for income taxes	28,212				33,945			73,659	97,681
Net income	86,253				102,265			221,677	297,775
Total assets	31,100,700			30,155,058				31,100,700
Loans held for sale	0			0				0
Total loans and leases	25,507,951			22,553,180				25,507,951
Total deposits	26,588,217			26,370,568				26,588,217
Mortgage Banking
Segment Reporting Information [Line Items]
Net interest income	1,072				2,726			3,909	9,431
Provision (recapture) for credit losses	0				0			0	0
Origination and sale	10,515				30,293			42,460	134,165
Servicing	9,529				9,172			28,174	27,379
Changes due to collection/realization of expected cash flows over time	(4,978)				(4,681)			(15,286)	(13,592)
Changes due to valuation inputs or assumptions	16,403				(634)			67,451	(4,326)
MSR hedge loss	(14,128)				0			(14,128)	0
Gain on sale of debt securities, net								0	0
Loss on equity securities, net	0				0			0	0
Gain on swap derivatives, net	0				0			0	0
Change in fair value of certain loans held for investment	0				0			0	0
Non-interest income (excluding above items)	185				188			557	680
Noninterest Income	17,526				34,338			109,228	144,306
Merger related expenses	0				0			0	0
Exit and disposal costs	0				0			0	0
Non-interest expense (excluding above items)	21,511				33,009			77,721	112,035
Allocated expenses, net	39				(3,680)			(7,398)	(3,860)
Total non-interest expense	21,550				29,329			70,323	108,175
Income before provision for income taxes	(2,952)				7,735			42,814	45,562
Provision for income taxes	(739)				1,934			10,703	11,391
Net income	(2,213)				$ 5,801			32,111	$ 34,171
Total assets	371,260			485,878				371,260
Loans held for sale	148,275			353,105				148,275
Total loans and leases	0			0				0
Total deposits	$ 228,890			$ 224,117				$ 228,890