Borrowing Arrangements (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Borrowing Arrangements
Investments securing FHLB advances, amortized cost	$ 490,513,000
Available-for-sale debt securities	484,001,000	$ 535,281,000
Federal funds purchased	0	0
Federal Home Loan Bank Advances
Borrowing Arrangements
Loans Pledged as Collateral	353,878,000
Remaining borrowing capacity	202,642,000
Federal Home Loan Bank Advances \| Securities Pledged as Collateral
Borrowing Arrangements
Investments securing FHLB advances, amortized cost	369,000	416,000
Available-for-sale debt securities	382,000	440,000
San Fransisco Branch
Borrowing Arrangements
Advances from FHLB	$ 30,000,000	$ 0

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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