Disclosures About Fair Value of Financial Instruments - Quantitative information about Level 3 fair value measurements (Unaudited) (Details 3) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate held for sale	$ 1,543	$ 1,610
Securities available for sale - Corporate	126,308	113,770
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale - Corporate	1,221	1,197
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	1,373	4,363
Valuation Techniques	Comparative sales based on independent appraisal	Comparative sales based on independent appraisal
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Impaired loans \| Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketability Discount	18.40%	10.00%
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Impaired loans \| Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketability Discount	100.00%	20.00%
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Real estate held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate held for sale	200	700
Valuation Techniques	Comparative sales based on independent appraisal	Comparative sales based on independent appraisal
Marketability Discount	41.50%
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Real estate held for sale \| Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketability Discount		10.00%
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Real estate held for sale \| Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketability Discount		20.00%
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale - Corporate	$ 1,221	$ 1,197
Valuation Techniques	Discounted cash flows	Discounted cash flows
Loss, given default	100.00%	100.00%
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Corporate \| Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Default probability	0.21%	0.21%
Discount rate	3.32%	3.32%
Recovery rate	0.00%	0.00%
Prepayment rate	0.00%	0.00%
Unobservable (Level 3) Inputs \| Fair Value, Measurements, Recurring \| Corporate \| Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Default probability	1.73%	1.73%
Discount rate	9.00%	9.00%
Recovery rate	15.00%	15.00%
Prepayment rate	40.00%	40.00%

Percentage of likelihood a loan will be recovered, used as an input to measure fair value.

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- Definition

Represent of Securities Received On Impaired Financing Receivables Fair Value Disclosure.

+ 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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- Definition

Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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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

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- Definition

Loss, including interest and principal, incurred on a defaulted security, expressed as a percentage of the original principal balance, used as an input to measure fair value.

+ References

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- Definition

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

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- Definition

Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.

+ References

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- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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