Employee Benefit And Stock Compensation Plans - Schedule Of Employee Stock Purchase Plan Activity (Details) - ESPP - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock Options and Awards
Increase in shares authorized for issuance	200,000
Discretionary contribution maximum match, as a percent of employee deductions			50.00%
Matching contributions made to plan		$ 0	$ 0	$ 0
Available ESPP shares - beginning of year		233,879	273,188	116,637
Plan amendment increasing available shares				200,000
Purchases		(36,813)	(39,309)	(43,449)
Available ESPP shares - end of year		197,066	233,879	273,188