Fair Value (Details Textual) $ in Millions	12 Months Ended
Dec. 31, 2015 Security	Dec. 31, 2014 Security	Dec. 31, 2013 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of debt securities with other-than-temporary impairment	1	1
Maturity period of short-term borrowings	one year or less
Period of swap rate	25 years
Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input discount rate	10.26%
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input discount rate	14.12%
Trust preferred securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
OTTI recognized value reflecting the estimated fair value of the securities \| $			$ 2.0
Number of debt securities with other-than-temporary impairment	1	1
Period frequency of projected prepayment rate	1 year	1 year
Projected Prepayments, minimum fixed rate coupons	8.00%	8.00%
Projected Prepayments, percentage of fair value input for banks	1.00%	1.00%
Projected prepayment, percentage of fair value for collateral by REITs	0.00%	0.00%
Projected prepayment, percentage of fair value for collateral for insurance companies	2.00%	2.00%
Annually projected defaults percentage for healthy banks	2.00%	2.00%
Period frequency of projected default rate	2 years	2 years
Projected defaults rate for healthy banks	0.36%	0.36%
Projected Recoveries, percentage for insurance companies, REITs and insolvent banks	0.00%	0.00%
Projected recovery, percentage for projected bank deferrals	10.00%	10.00%
Projected Bank Deferrals lagged	2 years	2 years
Trust preferred securities \| Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input discount rate	10.26%	10.24%
Trust preferred securities \| Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value input discount rate	14.12%	15.75%

Annually projected defaults percentage for healthy bank.

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Investments number of available for sale securities considered for other than temporary impairment losses investments.

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Period frequency of projected default rate.

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Period frequency of projected prepayment rate.

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Period of swap rate.

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Projected bank deferrals lagged.

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Projected defaults rate for healthy banks.

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Projected prepayment percentage of fair value for collateral.

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Projected prepayment percentage of fair value for collateral for insurance companies.

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Projected prepayment percentage of fair value input for banks.

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Projected prepayments minimum fixed rate coupons.

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Projected recovery percentage for insurance companies REITs and insolvent banks.

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Projected recovery percentage for projected bank deferrals.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Amount before tax of other than temporary impairment (OTTI) loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

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Description of the short-term debt arrangement, and disclosures pertaining to the underlying arrangements, including repayment terms, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements.

+ 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 210.5-02.19(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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