Loans and Lease Finance Receivables and Allowance for Credit Losses - Summary of loans by type and origination year, according to our internal risk ratings (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 942,055	$ 1,620,118
2021	1,615,163	1,183,367
2020	1,226,421	798,755
2019	810,164	677,205
2018	692,344	638,690
Prior	2,497,121	2,001,549
Revolving loans amortized cost basis	850,777	904,441
Revolving loans converted to term loans	58,184	63,588
Total	8,692,229	7,887,713
Commercial real estate loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	765,479	1,140,847
2021	1,250,049	984,337
2020	1,022,229	608,538
2019	639,493	557,498
2018	573,310	532,629
Prior	2,167,388	1,755,641
Revolving loans amortized cost basis	186,513	169,762
Revolving loans converted to term loans	39,167	40,478
Total	6,643,628	5,789,730
Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	6,679	10,511
2021	15,793	15,896
2020	14,730	7,236
2019	0	3,359
2018	5,672	0
Prior	0	0
Revolving loans amortized cost basis	17,710	25,262
Revolving loans converted to term loans	0	0
Total	60,584	62,264
SBA [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	35,072	70,929
2021	57,279	36,468
2020	35,900	11,129
2019	13,031	36,853
2018	32,537	46,652
Prior	123,097	86,569
Revolving loans amortized cost basis	193	0
Revolving loans converted to term loans	0
Total	297,109	288,600
SBA - Paycheck Protection Program (PPP) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		183,614
2021	61,623	2,971
2020	5,332	0
2019		0
2018		0
Prior		0
Revolving loans amortized cost basis		0
Revolving loans converted to term loans		0
Total	66,955	186,585
Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	77,558	147,294
2021	159,417	83,879
2020	89,608	127,376
2019	115,045	57,798
2018	55,570	33,354
Prior	104,651	74,101
Revolving loans amortized cost basis	331,205	279,019
Revolving loans converted to term loans	8,541	10,242
Total	941,595	813,063
Dairy And Livestock And Agribusiness [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	1,161	2,808
2021	5,607	942
2020	1,978	1,285
2019	1,038	1,072
2018	2,650	95
Prior	2,191	295
Revolving loans amortized cost basis	252,478	371,291
Revolving loans converted to term loans	6,491	8,431
Total	273,594	386,219
Municipal Lease Finance Receivables [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	170	9,310
2021	12,965	7,666
2020	7,281	0
2019	4,419	279
2018	5,136	9,528
Prior	34,466	19,150
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	64,437	45,933
SFR mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	46,924	48,821
2021	47,567	49,261
2020	47,783	41,776
2019	35,966	19,877
2018	17,169	16,046
Prior	63,910	64,017
Revolving loans amortized cost basis	500	451
Revolving loans converted to term loans	399	405
Total	260,218	240,654
Consumer Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	9,012	5,984
2021	4,863	1,947
2020	1,580	1,415
2019	1,172	469
2018	300	386
Prior	1,418	1,776
Revolving loans amortized cost basis	62,178	58,656
Revolving loans converted to term loans	3,586	4,032
Total	84,109	74,665
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	941,548	1,613,286
2021	1,603,049	1,160,790
2020	1,196,921	780,690
2019	786,903	646,886
2018	656,648	581,735
Prior	2,385,168	1,939,076
Revolving loans amortized cost basis	822,734	872,585
Revolving loans converted to term loans	43,873	44,388
Total	8,436,844	7,639,436
Pass [Member] | Commercial real estate loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	764,972	1,137,714
2021	1,240,209	963,697
2020	995,702	591,202
2019	621,334	534,468
2018	551,546	484,721
Prior	2,073,267	1,704,267
Revolving loans amortized cost basis	184,480	156,841
Revolving loans converted to term loans	33,667	33,564
Total	6,465,177	5,606,474
Pass [Member] | Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	6,679	10,511
2021	15,793	15,896
2020	14,730	7,236
2019	0
2018	1,391	0
Prior	0	0
Revolving loans amortized cost basis	17,710	25,262
Revolving loans converted to term loans	0	0
Total	56,303	58,905
Pass [Member] | SBA [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	35,072	70,929
2021	57,279	36,468
2020	35,800	11,129
2019	11,696	36,068
2018	30,565	38,504
Prior	108,573	78,527
Revolving loans amortized cost basis	193	0
Revolving loans converted to term loans	0
Total	279,178	271,625
Pass [Member] | SBA - Paycheck Protection Program (PPP) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		183,614
2021	61,488	2,969
2020	5,332	0
2019		0
2018		0
Prior		0
Revolving loans amortized cost basis		0
Revolving loans converted to term loans		0
Total	66,820	186,583
Pass [Member] | Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	77,558	145,494
2021	157,979	81,944
2020	87,899	126,647
2019	111,278	54,690
2018	49,685	32,455
Prior	103,779	73,600
Revolving loans amortized cost basis	313,334	267,659
Revolving loans converted to term loans	7,516	6,992
Total	909,028	789,481
Pass [Member] | Dairy And Livestock And Agribusiness [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	1,161	1,756
2021	5,607	942
2020	1,769	1,285
2019	1,038	1,035
2018	856	95
Prior	1,291	295
Revolving loans amortized cost basis	245,027	364,312
Revolving loans converted to term loans	0	454
Total	256,749	370,174
Pass [Member] | Municipal Lease Finance Receivables [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	170	9,310
2021	12,965	7,666
2020	7,281	0
2019	4,419	279
2018	5,136	9,528
Prior	33,976	18,811
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	63,947	45,594
Pass [Member] | SFR mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	46,924	48,813
2021	47,567	49,261
2020	46,828	41,776
2019	35,966	19,877
2018	17,169	16,046
Prior	62,879	61,965
Revolving loans amortized cost basis	500	451
Revolving loans converted to term loans	0	0
Total	257,833	238,189
Pass [Member] | Consumer Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	9,012	5,145
2021	4,162	1,947
2020	1,580	1,415
2019	1,172	469
2018	300	386
Prior	1,403	1,611
Revolving loans amortized cost basis	61,490	58,060
Revolving loans converted to term loans	2,690	3,378
Total	81,809	72,411
Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	507	6,588
2021	8,212	22,569
2020	13,256	14,604
2019	22,503	20,852
2018	22,163	47,712
Prior	83,290	47,260
Revolving loans amortized cost basis	22,763	23,909
Revolving loans converted to term loans	6,521	8,681
Total	179,215	192,175
Special Mention [Member] | Commercial real estate loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	507	3,133
2021	6,319	20,640
2020	10,283	14,477
2019	17,585	16,097
2018	14,802	43,262
Prior	77,666	44,045
Revolving loans amortized cost basis	2,033	6,970
Revolving loans converted to term loans	5,500	6,800
Total	134,695	155,424
Special Mention [Member] | Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0	0
2020	0	0
2019	0	3,359
2018	4,281	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	4,281	3,359
Special Mention [Member] | SBA [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0	0
2020	100	0
2019	1,335
2018	1,391	4,056
Prior	5,137	2,700
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	7,963	6,756
Special Mention [Member] | SBA - Paycheck Protection Program (PPP) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022
2021		0
2020		0
2019		0
2018		0
Prior		0
Revolving loans amortized cost basis		0
Revolving loans converted to term loans		0
Total		0
Special Mention [Member] | Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		1,556
2021	1,192	1,929
2020	1,709	127
2019	3,583	1,396
2018	1,689	394
Prior	186	26
Revolving loans amortized cost basis	16,190	9,369
Revolving loans converted to term loans	382	177
Total	24,931	14,974
Special Mention [Member] | Dairy And Livestock And Agribusiness [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		1,052
2021	0
2020	209	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	3,949	6,979
Revolving loans converted to term loans	639	1,301
Total	4,797	9,332
Special Mention [Member] | Municipal Lease Finance Receivables [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0
Prior	301	339
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	301	339
Special Mention [Member] | SFR mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		8
2021	0
2020	955	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	955	8
Special Mention [Member] | Consumer Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		839
2021	701
2020	0	0
2019	0	0
2018	0	0
Prior	0	150
Revolving loans amortized cost basis	591	591
Revolving loans converted to term loans	0	403
Total	1,292	1,983
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		244
2021	3,902	8
2020	16,244	3,461
2019	758	9,467
2018	13,533	9,243
Prior	28,663	15,213
Revolving loans amortized cost basis	5,280	7,947
Revolving loans converted to term loans	7,790	10,519
Total	76,170	56,102
Substandard [Member] | Commercial real estate loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	3,521	0
2020	16,244	2,859
2019	574	6,933
2018	6,962	4,646
Prior	16,455	7,329
Revolving loans amortized cost basis	0	5,951
Revolving loans converted to term loans	0	114
Total	43,756	27,832
Substandard [Member] | Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Substandard [Member] | SBA [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0	0
2020	0	0
2019	0	785
2018	581	4,092
Prior	9,387	5,342
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	9,968	10,219
Substandard [Member] | SBA - Paycheck Protection Program (PPP) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022
2021	135	2
2020		0
2019		0
2018		0
Prior		0
Revolving loans amortized cost basis		0
Revolving loans converted to term loans		0
Total	135	2
Substandard [Member] | Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		244
2021	246	6
2020		602
2019	184	1,712
2018	4,196	505
Prior	686	475
Revolving loans amortized cost basis	1,681	1,991
Revolving loans converted to term loans	643	3,073
Total	7,636	8,608
Substandard [Member] | Dairy And Livestock And Agribusiness [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	37
2018	1,794	0
Prior	900	0
Revolving loans amortized cost basis	3,502	0
Revolving loans converted to term loans	5,852	6,676
Total	12,048	6,713
Substandard [Member] | Municipal Lease Finance Receivables [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0	0
Prior	189	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	189	0
Substandard [Member] | SFR mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0
Prior	1,031	2,052
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	399	405
Total	1,430	2,457
Substandard [Member] | Consumer Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0	0
Prior	15	15
Revolving loans amortized cost basis	97	5
Revolving loans converted to term loans	896	251
Total	1,008	271
Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Doubtful [Member] | Commercial real estate loans [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Doubtful [Member] | Construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Doubtful [Member] | SBA [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	0
2021	0	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Doubtful [Member] | SBA - Paycheck Protection Program (PPP) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022
2021		0
2020		0
2019		0
2018		0
Prior		0
Revolving loans amortized cost basis		0
Revolving loans converted to term loans		0
Total		0
Doubtful [Member] | Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022
2021		0
2020		0
2019		0
2018		0
Prior		0
Revolving loans amortized cost basis		0
Revolving loans converted to term loans		0
Total		0
Doubtful [Member] | Dairy And Livestock And Agribusiness [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Doubtful [Member] | Municipal Lease Finance Receivables [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Doubtful [Member] | SFR mortgage [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	0	0
Doubtful [Member] | Consumer Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022		0
2021	0
2020	0	0
2019	0	0
2018	0	0
Prior	0	0
Revolving loans amortized cost basis	0	0
Revolving loans converted to term loans	0	0
Total	$ 0	$ 0