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Securities (Details 2) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Maturities of securities and their weighted average yields
Weighted Average Yield	3.67%
Amortized Cost	$ 131,272,000	$ 134,664,000
Available for sale securities/Fair Value	130,134,000	138,314,000
Due in 2013 [Member]
Maturities of securities and their weighted average yields
Weighted Average Yield	4.99%
Amortized Cost	1,130,000
Available for sale securities/Fair Value	1,134,000
Due in 2014 through 2018 [Member]
Maturities of securities and their weighted average yields
Weighted Average Yield	4.99%
Amortized Cost	4,650,000
Available for sale securities/Fair Value	4,785,000
Due in 2019 through 2023 [Member]
Maturities of securities and their weighted average yields
Weighted Average Yield	3.18%
Amortized Cost	28,545,000
Available for sale securities/Fair Value	28,060,000
Due in 2024 and beyond [Member]
Maturities of securities and their weighted average yields
Weighted Average Yield	3.59%
Amortized Cost	73,891,000
Available for sale securities/Fair Value	71,888,000
Mortgage-backed securities [Member]
Maturities of securities and their weighted average yields
Weighted Average Yield	5.20%
Amortized Cost	15,173,000	20,182,000
Available for sale securities/Fair Value	16,388,000	21,996,000
Michigan Strategic Fund bonds [Member]
Maturities of securities and their weighted average yields
Weighted Average Yield	2.15%
Amortized Cost	6,515,000	11,255,000
Available for sale securities/Fair Value	6,515,000	11,255,000
Mutual funds [Member]
Maturities of securities and their weighted average yields
Weighted Average Yield	2.04%
Amortized Cost	1,368,000	1,354,000
Available for sale securities/Fair Value	$ 1,364,000	$ 1,405,000

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- Definition

Weighted average yield of securities portfolio.

+ References

No definition available.

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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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