Fair Value Measurements (Fair Value Inputs, Assets, Quantitative Information) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Impaired loans	$ 6,565	$ 6,701
Other real estate owned	1,727	1,677	$ 3,274	$ 3,274
Level 3 | Impaired Loans
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Impaired loans	$ 140	$ 66
Valuation Techniques	Market approach	Market approach
Unobservable Input	Appraised value less selling costs of 5% to 10% Additional discounts of 5% to 90% to appraised value to reflect liquidation value	Appraised value less selling costs of 5% to 10% Additional discounts of 70% to 100% to appraised value to reflect liquidation value
Level 3 | Impaired Loans | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Selling costs (as a percent)	5.00%	5.00%
Discount to appraised value (as a percent)	5.00%	5.00%
Level 3 | Impaired Loans | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Selling costs (as a percent)	10.00%	10.00%
Discount to appraised value (as a percent)	90.00%	50.00%
Level 3 | Other Real Estate Owned
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	$ 50	$ 1,677
Valuation Techniques	Market approach	Market approach
Unobservable Input	Appraised value less selling costs of 5% to 10%	Appraised value less selling costs of 5% to 10%
Level 3 | Other Real Estate Owned | Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Selling costs (as a percent)	5.00%	5.00%
Level 3 | Other Real Estate Owned | Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Selling costs (as a percent)	10.00%	10.00%