Fair Values of Financial Instruments (Details Textual) - USD ($) $ in Thousands  | 
Dec. 31, 2016  | 
Dec. 31, 2015  | 
|---|---|---|
| Fair Values of Financial Instruments [Line Items] | ||
| Minimum Percentage of Defaults Rates on Above 3 Years Issuer Average in Other than Temporary Impairment Model Assumptions | 0.25% | |
| Maximum Percentage of Defaults Rates on Above 3 Years Issuer Average in Other than Temporary Impairment Model Assumptions | 5.00% | |
| Minimum Percentage of Recovery Assumptions on Other than Temporary Impairment Model Assumptions | 0.00% | |
| Maximum Percentage of Recovery Assumptions on Other than Temporary Impairment Model Assumptions | 15.00% | |
| Available-for-sale Securities, Amortized Cost Basis | $ 3,700 | $ 3,700 | 
| Unpaid Principal Balance | 3,500 | 7,400 | 
| Impaired Financing Receivable, Reserve | 1,200 | 356 | 
| Impaired Financing Receivable, Fair Value | $ 2,300 | $ 7,000 | 
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- Definition Fair Values of Financial Instruments No definition available. 
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- Definition The fair value of investment related to impaired financing receivables. No definition available. 
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- Definition The carrying amount of reserve related to impaired financing receivable. No definition available. 
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- Definition Maximum range percentage of defaults rates on above 3 years issuer average in other than temporary impairment model assumptions. No definition available. 
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- Definition Maximum range percentage of recovery assumptions in other than temporary impairment model assumptions. No definition available. 
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- Definition Minimum range percentage of defaults rates on above 3 years issuer average in other than temporary impairment model assumptions. No definition available. 
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- Definition Minimum range percentage of recovery assumptions in other than temporary impairment model assumptions. No definition available. 
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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