Securities Amortized costs and fair values of securities held to maturity (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	$ 1,500us-gaap_HeldToMaturitySecurities	$ 0us-gaap_HeldToMaturitySecurities
Gross unrealized gains	0
Gross unrealized losses	(103)
Fair value	1,397	0
Obligations of states and political subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	1,500
Gross unrealized gains	0
Gross unrealized losses	(103)
Fair value	$ 1,397

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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