Fair Value - Quantitative Information about Level 3 Fair Value Measurements (Details) - Non-recurring basis - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	$ 831	$ 2,702
Significant Unobservable Inputs (Level 3)
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	831	2,702
Commercial
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	190	1,333
Commercial | Significant Unobservable Inputs (Level 3)
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	190	1,333
Commercial | Significant Unobservable Inputs (Level 3) | Market Approach
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	$ 190	$ 1,333
Commercial | Significant Unobservable Inputs (Level 3) | Market Approach | Minimum
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)		0.00%
Commercial | Significant Unobservable Inputs (Level 3) | Market Approach | Maximum
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)	1.00%	5.00%
Commercial | Significant Unobservable Inputs (Level 3) | Market Approach | Weighted average
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)		5.00%
Commercial | Real estate
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	$ 440	$ 503
Commercial | Real estate | Significant Unobservable Inputs (Level 3)
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	440	503
Commercial | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	$ 440	$ 503
Commercial | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach | Minimum
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)	0.00%	0.00%
Commercial | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach | Maximum
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)	3.00%	3.00%
Commercial | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach | Weighted average
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)	3.00%	3.00%
Land and construction | Real estate
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	$ 201	$ 219
Land and construction | Real estate | Significant Unobservable Inputs (Level 3)
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	201	219
Land and construction | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value	$ 201	$ 219
Land and construction | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach | Maximum
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)	1.00%	1.00%
Home equity | Real estate
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value		$ 647
Home equity | Real estate | Significant Unobservable Inputs (Level 3)
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value		647
Home equity | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Impaired loans - held-for-investment, Fair Value		$ 647
Home equity | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach | Minimum
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)		0.00%
Home equity | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach | Maximum
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)		2.00%
Home equity | Real estate | Significant Unobservable Inputs (Level 3) | Market Approach | Weighted average
Quantitative information about level 3 fair value measurements for financial instruments measured at fair value on a non-recurring basis
Discount adjustment for differences between comparable sales (as a percent)		2.00%