Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Total	$ 7,251,064	$ 7,183,969
Nonaccrual	24,644	19,052	$ 66,291
Current
Financing Receivable, Past Due [Line Items]
Total	7,216,334	7,144,576
Total Past Due Loans
Financing Receivable, Past Due [Line Items]
Total	34,730	39,393
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total	7,259	18,093
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total	2,827	2,248
Commercial Loans | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	2,523,434	2,538,839
Nonaccrual	7,425	7,100	31,488
Commercial Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	1,493,519	1,510,392
Nonaccrual	7,075	283	15,239
Commercial Loans | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	376,855	381,963
Nonaccrual	384	384	2,471
Commercial Loans | Business banking
Financing Receivable, Past Due [Line Items]
Total	1,261,842	1,205,944
Nonaccrual	3,915	4,490	9,641
Commercial Loans | Current | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	2,514,689	2,523,315
Commercial Loans | Current | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	1,486,444	1,505,805
Commercial Loans | Current | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	376,471	381,579
Commercial Loans | Current | Business banking
Financing Receivable, Past Due [Line Items]
Total	1,255,124	1,199,586
Commercial Loans | Total Past Due Loans | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	8,745	15,524
Commercial Loans | Total Past Due Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	7,075	4,587
Commercial Loans | Total Past Due Loans | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	384	384
Commercial Loans | Total Past Due Loans | Business banking
Financing Receivable, Past Due [Line Items]
Total	6,718	6,358
Commercial Loans | 30-59 Days Past Due | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	0	8,424
Commercial Loans | 30-59 Days Past Due | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	0	4,304
Commercial Loans | 30-59 Days Past Due | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial Loans | 30-59 Days Past Due | Business banking
Financing Receivable, Past Due [Line Items]
Total	2,714	1,583
Commercial Loans | 60-89 Days Past Due | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	1,320	0
Commercial Loans | 60-89 Days Past Due | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial Loans | 60-89 Days Past Due | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial Loans | 60-89 Days Past Due | Business banking
Financing Receivable, Past Due [Line Items]
Total	89	285
Consumer Loans | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	1,475,575	1,421,953
Nonaccrual	5,529	6,526	7,294
Consumer Loans | Other consumer
Financing Receivable, Past Due [Line Items]
Total	119,839	124,878
Nonaccrual	316	269	$ 158
Consumer Loans | Current | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	1,464,321	1,409,907
Consumer Loans | Current | Other consumer
Financing Receivable, Past Due [Line Items]
Total	119,285	124,384
Consumer Loans | Total Past Due Loans | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	11,254	12,046
Consumer Loans | Total Past Due Loans | Other consumer
Financing Receivable, Past Due [Line Items]
Total	554	494
Consumer Loans | 30-59 Days Past Due | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	4,383	3,617
Consumer Loans | 30-59 Days Past Due | Other consumer
Financing Receivable, Past Due [Line Items]
Total	162	165
Consumer Loans | 60-89 Days Past Due | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	1,342	1,903
Consumer Loans | 60-89 Days Past Due | Other consumer
Financing Receivable, Past Due [Line Items]
Total	$ 76	$ 60