Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenue from Contracts with Customers
Net interest income	$ 145,147	$ 131,481	$ 279,019	$ 260,639
Not in scope of Topic 606	1,541	8,806	1,612	15,209
Total noninterest income	44,137	49,371	85,517	93,239
Total revenue	189,284	180,852	364,536	353,878
Retail Banking
Revenue from Contracts with Customers
Net interest income	107,368	97,106	201,416	191,560
Not in scope of Topic 606	1,160	1,868	2,252	5,222
Total noninterest income	22,485	22,495	45,800	46,070
Total revenue	129,853	119,601	247,216	237,630
Commercial Banking
Revenue from Contracts with Customers
Net interest income	36,826	40,234	71,914	78,500
Not in scope of Topic 606	1,469	2,282	3,387	3,604
Total noninterest income	20,415	19,528	39,070	35,569
Total revenue	57,241	59,762	110,984	114,069
Treasury and Other
Revenue from Contracts with Customers
Net interest income	953	(5,859)	5,689	(9,421)
Not in scope of Topic 606	(1,088)	4,656	(4,027)	6,383
Total noninterest income	1,237	7,348	647	11,600
Total revenue	2,190	1,489	6,336	2,179
Service charges on deposit accounts.
Revenue from Contracts with Customers
Revenue by type of service	6,843	6,632	14,344	13,350
Service charges on deposit accounts. | Retail Banking
Revenue from Contracts with Customers
Revenue by type of service	6,085	5,788	12,734	11,874
Service charges on deposit accounts. | Commercial Banking
Revenue from Contracts with Customers
Revenue by type of service	413	341	759	564
Service charges on deposit accounts. | Treasury and Other
Revenue from Contracts with Customers
Revenue by type of service	345	503	851	912
Credit and debit card fees
Revenue from Contracts with Customers
Revenue by type of service	16,449	16,132	30,691	30,085
Credit and debit card fees | Commercial Banking
Revenue from Contracts with Customers
Revenue by type of service	15,243	14,692	28,269	27,217
Credit and debit card fees | Treasury and Other
Revenue from Contracts with Customers
Revenue by type of service	1,206	1,440	2,422	2,868
Other service charges and fees.
Revenue from Contracts with Customers
Revenue by type of service	7,210	7,955	14,923	14,346
Other service charges and fees. | Retail Banking
Revenue from Contracts with Customers
Revenue by type of service	6,306	5,983	12,869	11,547
Other service charges and fees. | Commercial Banking
Revenue from Contracts with Customers
Revenue by type of service	417	1,590	1,198	2,065
Other service charges and fees. | Treasury and Other
Revenue from Contracts with Customers
Revenue by type of service	487	382	856	734
Trust and investment services income
Revenue from Contracts with Customers
Revenue by type of service	8,759	8,707	17,642	17,199
Trust and investment services income | Retail Banking
Revenue from Contracts with Customers
Revenue by type of service	8,759	8,707	17,642	17,199
Other.
Revenue from Contracts with Customers
Revenue by type of service	3,335	1,139	6,305	3,050
Other. | Retail Banking
Revenue from Contracts with Customers
Revenue by type of service	175	149	303	228
Other. | Commercial Banking
Revenue from Contracts with Customers
Revenue by type of service	2,873	623	5,457	2,119
Other. | Treasury and Other
Revenue from Contracts with Customers
Revenue by type of service	$ 287	$ 367	$ 545	$ 703