Loans and Allowance for Credit Losses (Schedule of Financing Receivables Past Due) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	$ 24,356,276	$ 24,885,988
1-4 single family residential
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	6,982,832	7,128,834
Financing Receivable, Originated in Current Fiscal Year	308,220	1,201,204
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,148,641	3,169,085
Financing Receivable, Originated Two Years before Latest Fiscal Year	3,014,862	922,591
Financing Receivable, Originated Three Years before Latest Fiscal Year	873,680	320,683
Financing Receivable, Originated Four Years before Latest Fiscal Year	303,616	182,814
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,333,813	1,332,457
US Government Agency Insured Loans
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	1,397,736	1,771,880
Pinnacle Public Finance [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	900,199	912,122
Financing Receivable, Originated in Current Fiscal Year	158,220	179,223
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	140,362	110,510
Financing Receivable, Originated Two Years before Latest Fiscal Year	78,322	66,592
Financing Receivable, Originated Three Years before Latest Fiscal Year	34,597	66,514
Financing Receivable, Originated Four Years before Latest Fiscal Year	56,848	29,783
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	431,850	459,500
Bridge - franchise finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	196,745	253,774
Financing Receivable, Originated in Current Fiscal Year	5,381	81,146
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	26,881	20,868
Financing Receivable, Originated Two Years before Latest Fiscal Year	38,426	40,601
Financing Receivable, Originated Three Years before Latest Fiscal Year	34,795	64,420
Financing Receivable, Originated Four Years before Latest Fiscal Year	46,244	31,816
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	44,684	14,923
Bridge - equipment finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	219,874	286,147
Financing Receivable, Originated in Current Fiscal Year	1,132	27,386
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	24,213	55,015
Financing Receivable, Originated Two Years before Latest Fiscal Year	45,515	16,488
Financing Receivable, Originated Three Years before Latest Fiscal Year	14,878	91,641
Financing Receivable, Originated Four Years before Latest Fiscal Year	64,472	33,264
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	69,664	62,353
Mortgage warehouse lending [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	407,577	524,740
Financing Receivable, Originated in Current Fiscal Year	0	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0	0
Commercial and industrial Portfolio Segment
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	8,509,256	8,308,534
Financing Receivable, Originated in Current Fiscal Year	1,036,410	1,906,814
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,660,362	839,326
Financing Receivable, Originated Two Years before Latest Fiscal Year	765,117	449,515
Financing Receivable, Originated Three Years before Latest Fiscal Year	383,842	796,508
Financing Receivable, Originated Four Years before Latest Fiscal Year	557,510	436,649
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,226,887	957,799
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	5,742,057	5,699,957
Financing Receivable, Originated in Current Fiscal Year	434,477	1,268,632
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,301,592	759,380
Financing Receivable, Originated Two Years before Latest Fiscal Year	689,131	570,236
Financing Receivable, Originated Three Years before Latest Fiscal Year	557,343	1,254,557
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,166,897	569,099
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,358,969	1,081,090
Current
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	23,737,531	24,020,014
Current | 1-4 single family residential
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	6,938,706	7,066,758
Financing Receivable, Originated in Current Fiscal Year	308,113	1,185,611
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,136,640	3,149,299
Financing Receivable, Originated Two Years before Latest Fiscal Year	3,003,418	916,923
Financing Receivable, Originated Three Years before Latest Fiscal Year	870,174	316,023
Financing Receivable, Originated Four Years before Latest Fiscal Year	302,053	177,891
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,318,308	1,321,011
Current | US Government Agency Insured Loans
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	872,098	1,025,523
Current | Pinnacle Public Finance [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	900,199	912,122
Current | Bridge - franchise finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	196,745	243,574
Current | Bridge - equipment finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	219,874	286,147
Current | Mortgage warehouse lending [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	407,577	524,740
Current | Commercial and industrial Portfolio Segment
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	8,475,471	8,280,321
Current | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	5,726,861	5,680,829
30 - 59 Days Past Due
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	168,369	210,634
30 - 59 Days Past Due | 1-4 single family residential
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	27,048	43,016
Financing Receivable, Originated in Current Fiscal Year	107	12,752
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	4,193	16,432
Financing Receivable, Originated Two Years before Latest Fiscal Year	11,097	3,266
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,456	2,953
Financing Receivable, Originated Four Years before Latest Fiscal Year	0	1,854
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	10,195	5,759
30 - 59 Days Past Due | US Government Agency Insured Loans
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	141,190	159,461
30 - 59 Days Past Due | Pinnacle Public Finance [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
30 - 59 Days Past Due | Bridge - franchise finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	1,321
30 - 59 Days Past Due | Bridge - equipment finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
30 - 59 Days Past Due | Mortgage warehouse lending [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
30 - 59 Days Past Due | Commercial and industrial Portfolio Segment
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	131	2,508
30 - 59 Days Past Due | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	4,328
60 - 89 Days Past Due
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	81,640	104,171
60 - 89 Days Past Due | 1-4 single family residential
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	2,639	4,076
Financing Receivable, Originated in Current Fiscal Year	0	252
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,681	1,196
Financing Receivable, Originated Two Years before Latest Fiscal Year	219	229
Financing Receivable, Originated Three Years before Latest Fiscal Year	0	1,347
Financing Receivable, Originated Four Years before Latest Fiscal Year	0	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	739	1,052
60 - 89 Days Past Due | US Government Agency Insured Loans
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	70,721	94,294
60 - 89 Days Past Due | Pinnacle Public Finance [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
60 - 89 Days Past Due | Bridge - franchise finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
60 - 89 Days Past Due | Bridge - equipment finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
60 - 89 Days Past Due | Mortgage warehouse lending [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
60 - 89 Days Past Due | Commercial and industrial Portfolio Segment
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	6,276	1,028
60 - 89 Days Past Due | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	2,004	4,773
90 Days or More Past Due
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	368,736	551,169
90 Days or More Past Due | 1-4 single family residential
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	14,439	14,984
Financing Receivable, Originated in Current Fiscal Year	0	2,589
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	6,127	2,158
Financing Receivable, Originated Two Years before Latest Fiscal Year	128	2,173
Financing Receivable, Originated Three Years before Latest Fiscal Year	2,050	360
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,563	3,069
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	4,571	4,635
90 Days or More Past Due | US Government Agency Insured Loans
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	313,727	492,602
90 Days or More Past Due | Pinnacle Public Finance [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
90 Days or More Past Due | Bridge - franchise finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	8,879
90 Days or More Past Due | Bridge - equipment finance
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
90 Days or More Past Due | Mortgage warehouse lending [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	0	0
90 Days or More Past Due | Commercial and industrial Portfolio Segment
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	27,378	24,677
90 Days or More Past Due | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable Investment Past Due [Line Items]
Financing Receivable, before Allowance for Credit Loss and Fee	$ 13,192	$ 10,027