XML 120 R106.htm IDEA: XBRL DOCUMENT v3.6.0.2
Retirement and Share-based Compensation Plans (Defined Contribution Plan) (Details) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]      
Defined contribution plan, maximum annual employee contribution $ 18,000 $ 18,000 $ 17,500
Defined contribution plan, employer plan contributions $ 1,300,000 $ 400,000 $ 400,000