Treasury Stock Treasury Stock Narrative Data (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized to be repurchased per quarter	3,000	2,500
Purchase of treasury stock, cost	$ 6	$ 94	$ 45
Number of shares of common stock repurchased since inception of stock repurchase program	13,754
Cost per share of common stock repurchased since inception of stock repurchase program, low	$ 17.86
Cost per share of common stock repurchased since inception of stock repurchase program, high	$ 26.67
Total cost of common stock repurchased since inception of stock repurchase program	$ 291
Number of shares of common stock reserved for issuance and sale under the DRIP	200,000
Common Stock
Equity, Class of Treasury Stock [Line Items]
Purchase of treasury stock, shares	213	3,753	1,939
Shares issued under the DRIP	315
Treasury Stock
Equity, Class of Treasury Stock [Line Items]
Purchase of treasury stock, cost	$ 6	$ 94	$ 45