Borrowing Arrangements (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Borrowing Arrangements
Investments securing FHLB advances, amortized cost	$ 772,677,000	$ 1,098,373,000
Available-for-sale debt securities	668,300,000	1,109,208,000
Federal funds purchased	0	0
Asset Pledged as Collateral
Borrowing Arrangements
Available-for-sale debt securities	177,503,000
Federal Home Loan Bank Advances
Borrowing Arrangements
Remaining borrowing capacity	277,058,000
Investments securing FHLB advances, amortized cost	90,000	112,000
Available-for-sale debt securities	95,000	117,000
Federal Home Loan Bank Advances \| Asset Pledged as Collateral
Borrowing Arrangements
Debt Securities	472,949,000
San Fransisco Branch
Borrowing Arrangements
Advances from FHLB	$ 25,000,000	$ 0

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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