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Securities (Details) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Amortized cost and fair value of available for sale securities and related pre-tax gross unrealized gains and losses
Amortized Cost	$ 131,272,000	$ 134,664,000
Gross Unrealized Gains	2,393,000	4,038,000
Gross Unrealized Losses	(3,531,000)	(388,000)
Fair Value	130,134,000	138,314,000
U.S. Government agency debt obligations [Member]
Amortized cost and fair value of available for sale securities and related pre-tax gross unrealized gains and losses
Amortized Cost	89,941,000	78,447,000
Gross Unrealized Gains	535,000	1,039,000
Gross Unrealized Losses	(3,527,000)	(388,000)
Fair Value	86,949,000	79,098,000
Mortgage-backed securities [Member]
Amortized cost and fair value of available for sale securities and related pre-tax gross unrealized gains and losses
Amortized Cost	15,173,000	20,182,000
Gross Unrealized Gains	1,215,000	1,814,000
Gross Unrealized Losses	0	0
Fair Value	16,388,000	21,996,000
Michigan Strategic Fund bonds [Member]
Amortized cost and fair value of available for sale securities and related pre-tax gross unrealized gains and losses
Amortized Cost	6,515,000	11,255,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	6,515,000	11,255,000
Municipal general obligation bonds [Member]
Amortized cost and fair value of available for sale securities and related pre-tax gross unrealized gains and losses
Amortized Cost	17,397,000	21,700,000
Gross Unrealized Gains	596,000	1,043,000
Gross Unrealized Losses	0	0
Fair Value	17,993,000	22,743,000
Municipal revenue bonds [Member]
Amortized cost and fair value of available for sale securities and related pre-tax gross unrealized gains and losses
Amortized Cost	878,000	1,726,000
Gross Unrealized Gains	47,000	91,000
Gross Unrealized Losses	0	0
Fair Value	925,000	1,817,000
Mutual funds [Member]
Amortized cost and fair value of available for sale securities and related pre-tax gross unrealized gains and losses
Amortized Cost	1,368,000	1,354,000
Gross Unrealized Gains	0	51,000
Gross Unrealized Losses	(4,000)	0
Fair Value	$ 1,364,000	$ 1,405,000

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- Definition

Available for sale securities gross unrealized gains accumulated in investments.

+ References

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- Definition

Available for sale securities gross unrealized loss accumulated in investments.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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This item represents the cost of debt and equity 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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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