Loans - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 56,241	$ 53,964	$ 54,658	$ 52,435	$ 52,435
Additions (deductions)
Provision for credit losses	1,510	1,355	3,400	3,840
Recoveries credited to the allowance	711	757	2,106	2,082
Loans charged against the allowance	(1,018)	(581)	(2,720)	(2,862)
Balance at end of period	57,444	55,495	57,444	55,495	54,658
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	18,979	16,284	16,724	13,817	13,817
Additions (deductions)
Provision for credit losses	1,082	1,112	3,199	4,350
Recoveries credited to the allowance	101	178	239	436
Loans charged against the allowance	0	(24)	0	(1,053)	(1,054)
Balance at end of period	20,162	17,550	20,162	17,550	16,724
Mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	20,731	20,080	21,386	21,633	21,633
Additions (deductions)
Provision for credit losses	(1,004)	(170)	(1,524)	(1,835)
Recoveries credited to the allowance	131	112	270	255
Loans charged against the allowance	(26)	0	(300)	(31)	(154)
Balance at end of period	19,832	20,022	19,832	20,022	21,386
Installment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	3,901	4,315	4,126	4,290	4,290
Additions (deductions)
Provision for credit losses	1,156	(42)	1,241	280
Recoveries credited to the allowance	479	467	1,597	1,391
Loans charged against the allowance	(992)	(557)	(2,420)	(1,778)
Balance at end of period	4,544	4,183	4,544	4,183	4,126
Subjective Allocation
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	12,630	13,285	12,422	12,695	12,695
Additions (deductions)
Provision for credit losses	276	455	484	1,045
Recoveries credited to the allowance	0	0	0	0
Loans charged against the allowance	0	0	0	0
Balance at end of period	$ 12,906	$ 13,740	$ 12,906	$ 13,740	$ 12,422