Investments (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015 Number	Dec. 31, 2014 Number
Schedule of Available-for-sale Securities [Line Items]
No. of securities	124	189
Fair value, Less than 12 months	$ 31,413	$ 56,580
Unrealized losses, Less than 12 months	(238)	(249)
Fair value, 12 months or longer	30,029	59,873
Unrealized losses, 12 months or longer	(288)	(1,261)
Total, Fair value	61,442	116,453
Total, Unrealized losses	(526)	(1,510)
U. S. treasury securities [Member]
Schedule of Available-for-sale Securities [Line Items]
No. of securities		1
Fair value, Less than 12 months		2,960
Unrealized losses, Less than 12 months		(1)
Fair value, 12 months or longer		0
Unrealized losses, 12 months or longer		0
Total, Fair value		2,960
Total, Unrealized losses		(1)
Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
No. of securities	6	14
Fair value, Less than 12 months	0	7,361
Unrealized losses, Less than 12 months	0	(14)
Fair value, 12 months or longer	10,636	11,958
Unrealized losses, 12 months or longer	(70)	(260)
Total, Fair value	10,636	19,319
Total, Unrealized losses	(70)	(274)
Nontaxable Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
No. of securities	59	71
Fair value, Less than 12 months	14,601	13,927
Unrealized losses, Less than 12 months	(108)	(66)
Fair value, 12 months or longer	2,847	7,329
Unrealized losses, 12 months or longer	(33)	(114)
Total, Fair value	17,448	21,256
Total, Unrealized losses	(141)	(180)
Taxable Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
No. of securities	38	74
Fair value, Less than 12 months	8,098	14,797
Unrealized losses, Less than 12 months	(83)	(92)
Fair value, 12 months or longer	9,720	14,827
Unrealized losses, 12 months or longer	(100)	(258)
Total, Fair value	17,818	29,624
Total, Unrealized losses	(183)	(350)
Collateralized Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
No. of securities	21	29
Fair value, Less than 12 months	8,714	17,535
Unrealized losses, Less than 12 months	(47)	(76)
Fair value, 12 months or longer	6,826	25,759
Unrealized losses, 12 months or longer	(85)	(629)
Total, Fair value	15,540	43,294
Total, Unrealized losses	$ (132)	$ (705)

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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