Stock-Based Compensation Plans ESPP (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Percentage of fair value at purchase date	85.00%
Discount from market price, purchase date	15.00%
ESPP shares purchased	109,665	121,890	132,640
Average purchase price per share (85% of market value)	$ 12.37	$ 10.86	$ 10.31
Compensation expense recognized (in thousands)	$ 240	$ 234	$ 241