Disclosures About Fair Value of Assets and Liabilities - Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements Other Than Goodwill (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013
Discounted Cash Flow | State and municipal | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Maturity/Call date	1 month
Blend of US Muni BQ curve	A-
Discount rate	1.00%
Discounted Cash Flow | State and municipal | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Maturity/Call date	11 years
Blend of US Muni BQ curve	BBB-
Discount rate	4.00%
Discounted Cash Flow | Corporate obligations
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk free rate	3 month LIBOR
Discount to reflect current market conditions	2.00%
Collateral Based Measurements | Impaired loans (collateral dependent) | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability	0.00%
Collateral Based Measurements | Impaired loans (collateral dependent) | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability	50.00%
Appraisals | Other real estate owned | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions	0.00%
Appraisals | Other real estate owned | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount to reflect current market conditions	20.00%
Significant Unobservable Inputs (Level 3) | Discounted Cash Flow | State and municipal
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 17,163
Significant Unobservable Inputs (Level 3) | Discounted Cash Flow | Corporate obligations
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	752
Significant Unobservable Inputs (Level 3) | Collateral Based Measurements | Impaired loans (collateral dependent)
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	14,230
Significant Unobservable Inputs (Level 3) | Appraisals | Other real estate owned
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value	$ 7,949