Investment Securities - Summary Of Interest Income On Available-For-Sale Investment Securities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Total taxable interest income	$ 2,651us-gaap_InterestIncomeSecuritiesTaxable	$ 2,035us-gaap_InterestIncomeSecuritiesTaxable	$ 2,223us-gaap_InterestIncomeSecuritiesTaxable
Total tax-exempt interest income	391	568	573
Total interest income	3,042	2,603	2,796
U.S. Treasury and government sponsored entities
Schedule of Available-for-sale Securities [Line Items]
Total taxable interest income	1,769	898	941
U.S. Agency Mortgage-backed Securities
Schedule of Available-for-sale Securities [Line Items]
Total taxable interest income	25	1	2
Other
Schedule of Available-for-sale Securities [Line Items]
Total taxable interest income	857	1,136	1,280
Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Total tax-exempt interest income	$ 391	$ 568	$ 573

Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24721-111560

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 2, 3

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.2,3)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.2)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 2

-Article 9

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

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