Estimated Fair Value of Financial Instruments - Balances of Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a nonrecurring basis	$ 550	$ 1,508
Commercial real estate | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans: Commercial Real Estate	550	1,508
Quoted Market Prices in Active Markets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a nonrecurring basis	0	0
Quoted Market Prices in Active Markets (Level 1) | Commercial real estate | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans: Commercial Real Estate	0	0
Internal Models with Significant Observable Market Parameters (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a nonrecurring basis	0	0
Internal Models with Significant Observable Market Parameters (Level 2) | Commercial real estate | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans: Commercial Real Estate	0	0
Internal Models with Significant Unobservable Market Parameters (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans: Commercial Real Estate	922,922	913,844
Internal Models with Significant Unobservable Market Parameters (Level 3) | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a nonrecurring basis	550	1,508
Internal Models with Significant Unobservable Market Parameters (Level 3) | Commercial real estate | Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Loans: Commercial Real Estate	$ 550	$ 1,508