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Securities (Details 2) (USD $) | Jun. 30, 2013 | Dec. 31, 2012
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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 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 + Details
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