Securities (Details Textual) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Securities (Textual) [Abstract]
Fair value of debt securities with unrealized losses	$ 73,782,000	$ 33,555,000
Aggregate depreciation of securities with unrealized losses	(3,531,000)	(388,000)
Available for sale securities/Fair Value	130,134,000	138,314,000
Securities (Additional Textual) [Abstract]
Total securities of specific issuer, other than U.S. Government and its agencies, maximum percentage of stockholders' equity	10.00%
Debt securities and mutual funds [Member]
Securities (Textual) [Abstract]
Number of debt securities with unrealized losses	52
Number of mutual funds with unrealized losses	1
Fair value of debt securities with unrealized losses	73,800,000
Aggregate depreciation of securities with unrealized losses	3,500,000
State of Michigan and all its political subdivisions [Member]
Securities (Textual) [Abstract]
Amortized cost of securities	18,300,000	23,400,000
Available for sale securities/Fair Value	18,900,000	24,600,000
U.S. Government agency debt obligations and mortgage-backed securities [Member]
Securities (Textual) [Abstract]
Carrying value of securities pledged to secure repurchase agreements	$ 82,800,000	$ 83,800,000

Available for sale securities continuous unrealized loss position aggregate losses accumulated in investments.

No definition available.

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- Definition

Number of debt securities with unrealized losses.

+ References

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Number of mutual funds with unrealized losses.

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- Definition

Securities of specific issuer other than U.S. Government and its agencies, maximum percentage of stockholders' equity.

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No definition available.

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- Definition

This item represents the cost of debt 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

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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

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-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

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-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 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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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- Definition

The carrying amount of securities categorized neither as held-to-maturity nor trading which serve as security for borrowings or other arrangements.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 9

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph b

-Article 4

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX210.4-08(b))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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