Fair Value Measurements - Fair Value on Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financial assets:
Debt securities available for sale	$ 1,018,379	$ 1,328,634
Debt securities held to maturity	351,927	370,391
Equity securities	3,633	3,384
Derivative assets	36,205	19,756
Financial liabilities:
Derivative liabilities	23,015	19,072
Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and cash equivalents	204,484	179,228
Debt securities available for sale	86,444	55,178
Debt securities held to maturity	0	0
Equity securities	3,314	3,053
Federal Home Loan Bank stock	0	0
Loans receivable, net	0	0
Derivative assets	0	0
Financial liabilities:
Deposits	0	0
Borrowings	0	0
Derivative liabilities	0	0
Significant Other Observable Inputs (Level 2)
Financial assets:
Cash and cash equivalents	0	0
Debt securities available for sale	921,647	1,261,333
Debt securities held to maturity	351,927	370,391
Equity securities	319	331
Federal Home Loan Bank stock	71,869	58,114
Loans receivable, net	0	0
Derivative assets	36,205	19,756
Financial liabilities:
Deposits	7,668,864	7,942,782
Borrowings	1,342,885	1,146,265
Derivative liabilities	23,015	19,072
Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and cash equivalents	0	0
Debt securities available for sale	10,288	12,123
Debt securities held to maturity	0	0
Equity securities	0	0
Federal Home Loan Bank stock	0	0
Loans receivable, net	6,847,626	6,771,095
Derivative assets	0	0
Financial liabilities:
Deposits	0	0
Borrowings	0	0
Derivative liabilities	0	0
Carrying Value
Financial assets:
Cash and cash equivalents	204,484	179,228
Debt securities available for sale	1,018,379	1,328,634
Debt securities held to maturity	411,945	421,523
Equity securities	3,633	3,384
Federal Home Loan Bank stock	71,869	58,114
Loans receivable, net	7,786,427	7,624,761
Derivative assets	36,205	19,756
Financial liabilities:
Deposits	7,703,166	8,001,159
Borrowings	1,356,218	1,127,047
Derivative liabilities	23,015	19,072
Total Fair Value
Financial assets:
Cash and cash equivalents	204,484	179,228
Debt securities available for sale	1,018,379	1,328,634
Debt securities held to maturity	351,927	370,391
Equity securities	3,633	3,384
Federal Home Loan Bank stock	71,869	58,114
Loans receivable, net	6,847,626	6,771,095
Derivative assets	36,205	19,756
Financial liabilities:
Deposits	7,668,864	7,942,782
Borrowings	1,342,885	1,146,265
Derivative liabilities	$ 23,015	$ 19,072