Allowance for Credit Losses - Summary of loans in Accrual and Nonaccrual Status (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable Recorded Investment [Line Items]
Total loans	$ 129,492,304	$ 92,040,032
30-89 Days Past Due	1,779,054	845,930
Accruing Loans Past Due 90 Days or More	491,018	963,399
Nonaccrual	2,438,435	2,060,083
Loans and leases, net of unearned discount	131,564,163	92,912,452
Revolving Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	26,197,545	16,234,904
Revolving Loans Converted to Term Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	1,664,096	1,199,887
Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	595,897	239,561
Accruing Loans Past Due 90 Days or More	345,402	920,080
Nonaccrual	272,090	355,858
Loans and leases, net of unearned discount	22,704,895	14,810,371
Residential [Member] | Revolving Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	499
Nonaccrual	7,353	263
Loans and leases, net of unearned discount	38,292	72,572
Residential Limited Documentation [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	22,456	16,666
Nonaccrual	77,814	122,888
Loans and leases, net of unearned discount	1,051,052	1,264,074
Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	30,787	15,486
Nonaccrual	84,788	70,488
Loans and leases, net of unearned discount	5,006,886	3,562,591
Home Equity Lines and Loans [Member] | Revolving Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due		346
Nonaccrual	2,799	4,951
Loans and leases, net of unearned discount	3,265,332	2,353,576
Home Equity Lines and Loans [Member] | Revolving Loans Converted to Term Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	28,460	14,421
Nonaccrual	74,646	59,787
Loans and leases, net of unearned discount	1,590,440	1,156,983
Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	54,593	40,544
Nonaccrual	44,630	27,811
Loans and leases, net of unearned discount	9,073,394	8,053,528
Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	44,486	40,064
Nonaccrual	39,584	34,037
Loans and leases, net of unearned discount	4,477,276	4,678,873
Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	22,961	12,223
Accruing Loans Past Due 90 Days or More	4,869	3,302
Nonaccrual	49,497	44,289
Loans and leases, net of unearned discount	2,035,523	1,679,961
Other [Member] | Revolving Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	15,655	1,908
Accruing Loans Past Due 90 Days or More	4,643
Nonaccrual	44,449	40,807
Loans and leases, net of unearned discount	1,439,796	1,190,811
Other [Member] | Revolving Loans Converted to Term Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	651	434
Nonaccrual	185	129
Loans and leases, net of unearned discount	9,057	2,068
Current [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	126,855,656	89,043,040
Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	21,491,506	13,294,872
Current [Member] | Residential [Member] | Revolving Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	30,440	72,309
Current [Member] | Residential Limited Documentation [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	950,782	1,124,520
Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	4,891,311	3,476,617
Current [Member] | Home Equity Lines and Loans [Member] | Revolving Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	3,262,533	2,348,279
Current [Member] | Home Equity Lines and Loans [Member] | Revolving Loans Converted to Term Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	1,487,334	1,082,775
Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	8,974,171	7,985,173
Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	4,393,206	4,604,772
Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	1,958,196	1,620,147
Current [Member] | Other [Member] | Revolving Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	1,375,049	1,148,096
Current [Member] | Other [Member] | Revolving Loans Converted to Term Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	8,221	1,505
Term Loans 2022 [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	24,853,925
Term Loans 2022 [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	59,477
Accruing Loans Past Due 90 Days or More	12,012
Nonaccrual	5,686
Loans and leases, net of unearned discount	5,148,554
Term Loans 2022 [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	930
Term Loans 2022 [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	8,648
Nonaccrual	3,533
Loans and leases, net of unearned discount	2,854,272
Term Loans 2022 [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	6,926
Nonaccrual	2,493
Loans and leases, net of unearned discount	1,500,495
Term Loans 2022 [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	3,783
Nonaccrual	2,745
Loans and leases, net of unearned discount	281,058
Term Loans 2022 [Member] | Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	5,071,379
Term Loans 2022 [Member] | Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	930
Term Loans 2022 [Member] | Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	2,842,091
Term Loans 2022 [Member] | Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	1,491,076
Term Loans 2022 [Member] | Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	274,530
Term Loans 2021 [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	18,747,757	18,817,411
Term Loans 2021 [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	51,308	15,245
Accruing Loans Past Due 90 Days or More	39,934	10,924
Nonaccrual	10,865	3,359
Loans and leases, net of unearned discount	4,103,759	3,086,646
Term Loans 2021 [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Nonaccrual	15
Loans and leases, net of unearned discount	2,124	304
Term Loans 2021 [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	9,525	5,929
Nonaccrual	7,440	1,341
Loans and leases, net of unearned discount	2,297,592	2,897,381
Term Loans 2021 [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	13,324	8,508
Nonaccrual	10,698	1,588
Loans and leases, net of unearned discount	1,581,698	2,230,157
Term Loans 2021 [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	1,450	2,937
Nonaccrual	830	2,051
Loans and leases, net of unearned discount	174,518	249,334
Term Loans 2021 [Member] | Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	4,001,652	3,057,118
Term Loans 2021 [Member] | Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	2,109	304
Term Loans 2021 [Member] | Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	2,280,627	2,890,111
Term Loans 2021 [Member] | Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	1,557,676	2,220,061
Term Loans 2021 [Member] | Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	172,238	244,346
Term Loans 2020 [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	13,072,920	12,376,366
Term Loans 2020 [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	40,337	12,535
Accruing Loans Past Due 90 Days or More	20,067	100,581
Nonaccrual	2,583	19,858
Loans and leases, net of unearned discount	2,780,358	1,805,064
Term Loans 2020 [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	2,441	777
Term Loans 2020 [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	12,412	8,912
Nonaccrual	9,427	4,646
Loans and leases, net of unearned discount	1,609,468	2,101,900
Term Loans 2020 [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	7,284	6,615
Nonaccrual	7,372	4,390
Loans and leases, net of unearned discount	717,367	1,108,689
Term Loans 2020 [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	326	404
Nonaccrual	332	326
Loans and leases, net of unearned discount	58,997	97,675
Term Loans 2020 [Member] | Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	2,717,371	1,672,090
Term Loans 2020 [Member] | Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	2,441	777
Term Loans 2020 [Member] | Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	1,587,629	2,088,342
Term Loans 2020 [Member] | Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	702,711	1,097,684
Term Loans 2020 [Member] | Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	58,339	96,945
Term Loans 2019 [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	12,737,602	12,286,933
Term Loans 2019 [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	21,849	9,886
Accruing Loans Past Due 90 Days or More	14,050	28,512
Nonaccrual	9,860	7,119
Loans and leases, net of unearned discount	1,438,625	1,121,413
Term Loans 2019 [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	171
Nonaccrual	536
Loans and leases, net of unearned discount	16,068	2,793
Term Loans 2019 [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	8,387	8,317
Nonaccrual	7,625	4,871
Loans and leases, net of unearned discount	979,919	1,281,117
Term Loans 2019 [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	7,239	8,936
Nonaccrual	7,520	7,847
Loans and leases, net of unearned discount	393,721	678,783
Term Loans 2019 [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	386	472
Nonaccrual	371	326
Loans and leases, net of unearned discount	39,196	74,384
Term Loans 2019 [Member] | Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	1,392,866	1,075,896
Term Loans 2019 [Member] | Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	15,361	2,793
Term Loans 2019 [Member] | Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	963,907	1,267,929
Term Loans 2019 [Member] | Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	378,962	662,000
Term Loans 2019 [Member] | Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	38,439	73,586
Term Loans 2018 [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	7,534,367	7,895,140
Term Loans 2018 [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	23,126	6,132
Accruing Loans Past Due 90 Days or More	14,007	31,996
Nonaccrual	4,650	4,577
Loans and leases, net of unearned discount	795,691	508,745
Term Loans 2018 [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	126	21
Nonaccrual	334
Loans and leases, net of unearned discount	23,781	1,751
Term Loans 2018 [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	5,202	5,074
Nonaccrual	5,344	4,918
Loans and leases, net of unearned discount	497,510	656,875
Term Loans 2018 [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	5,464	7,161
Nonaccrual	5,620	7,867
Loans and leases, net of unearned discount	178,522	356,683
Term Loans 2018 [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	141	255
Nonaccrual	120	193
Loans and leases, net of unearned discount	8,478	24,872
Term Loans 2018 [Member] | Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	753,908	466,040
Term Loans 2018 [Member] | Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	23,321	1,730
Term Loans 2018 [Member] | Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	486,964	646,883
Term Loans 2018 [Member] | Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	167,438	341,655
Term Loans 2018 [Member] | Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	8,217	24,424
Term Loans 2017 [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount		5,558,871
Term Loans 2017 [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due		33,097
Accruing Loans Past Due 90 Days or More		205,318
Nonaccrual		5,890
Loans and leases, net of unearned discount		1,282,263
Term Loans 2017 [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount		1,944
Term Loans 2017 [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due		5,189
Nonaccrual		4,039
Loans and leases, net of unearned discount		455,096
Term Loans 2017 [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due		5,715
Nonaccrual		6,882
Loans and leases, net of unearned discount		224,371
Term Loans 2017 [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due		101
Nonaccrual		104
Loans and leases, net of unearned discount		17,129
Term Loans 2017 [Member] | Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans		1,037,958
Term Loans 2017 [Member] | Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans		1,944
Term Loans 2017 [Member] | Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans		445,868
Term Loans 2017 [Member] | Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans		211,774
Term Loans 2017 [Member] | Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans		16,924
Term Loans Prior Period [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and leases, net of unearned discount	26,755,951	18,542,940
Term Loans Prior Period [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	399,301	162,666
Accruing Loans Past Due 90 Days or More	245,332	542,749
Nonaccrual	231,093	314,792
Loans and leases, net of unearned discount	8,399,616	6,933,668
Term Loans Prior Period [Member] | Residential Limited Documentation [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	22,456	16,666
Nonaccrual	77,814	122,888
Loans and leases, net of unearned discount	1,051,052	1,264,074
Term Loans Prior Period [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	2,030	698
Nonaccrual	6,458	5,750
Loans and leases, net of unearned discount	105,770	44,463
Term Loans Prior Period [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	10,419	7,123
Nonaccrual	11,261	7,996
Loans and leases, net of unearned discount	834,633	661,159
Term Loans Prior Period [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	4,249	3,129
Nonaccrual	5,881	5,463
Loans and leases, net of unearned discount	105,473	80,190
Term Loans Prior Period [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
30-89 Days Past Due	569	5,712
Accruing Loans Past Due 90 Days or More	226	3,302
Nonaccrual	465	353
Loans and leases, net of unearned discount	24,423	23,688
Term Loans Prior Period [Member] | Current [Member] | Residential [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	7,523,890	5,913,461
Term Loans Prior Period [Member] | Current [Member] | Residential Limited Documentation [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	950,782	1,124,520
Term Loans Prior Period [Member] | Current [Member] | Home Equity Lines and Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	97,282	38,015
Term Loans Prior Period [Member] | Current [Member] | Recreational Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	812,953	646,040
Term Loans Prior Period [Member] | Current [Member] | Automobile [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	95,343	71,598
Term Loans Prior Period [Member] | Current [Member] | Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	$ 23,163	$ 14,321