Investment Securities - Securities Sold and Pledged as Collateral (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financial Instruments Owned and Pledged as Collateral [Line Items]
Proceeds from sale of available-for-sale securities	$ 2,099	$ 2,436	$ 7,973
Available-for-sale Securities, Gross Realized Gains	7	4	86
Proceeds from sale of held-to-maturity securities	1,015	2,146	6,442
Net loss on sale of available for sale securities sold	(1)	(28)	(104)
Net gain on sale of held to maturity securities sold	73	104	67
Held-to-maturity Securities, Sold Security, Realized Loss	0	0	$ (50)
State of California
Financial Instruments Owned and Pledged as Collateral [Line Items]
Available-for-sale securities pledged as collateral	87,900	74,700
Public Deposits
Financial Instruments Owned and Pledged as Collateral [Line Items]
Available-for-sale securities pledged as collateral	87,100	73,800
Trust Deposits
Financial Instruments Owned and Pledged as Collateral [Line Items]
Available-for-sale securities pledged as collateral	840	856
Internal checking account
Financial Instruments Owned and Pledged as Collateral [Line Items]
Available-for-sale securities pledged as collateral	$ 1,100	$ 1,100

Held-to-maturity Securities, Sold Security, Realized Gains

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- Definition

Held-to-maturity Securities, Sold Security, Realized Losses

+ References

No definition available.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585

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- Definition

The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585

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