Annual report pursuant to Section 13 and 15(d)

Debt (CredAg) (Details)

v3.6.0.2
Debt (CredAg) (Details) - USD ($)
$ in Thousands
12 Months Ended
Nov. 19, 2015
Dec. 08, 2014
Jun. 19, 2014
Dec. 31, 2016
Credit Agreement        
Debt        
Credit facility amount $ 100,000 $ 100,000 $ 70,000  
Increase credit facility, amount   $ 25,000 $ 25,000  
Commitment fee   0.25% 0.25%  
Amount outstanding       $ 0
Voting equity of foreign subsidiary pledged (as a percent) 66.00%      
Non-voting equity of foreign subsidiary pledged (as a percent) 100.00%      
Debt instrument covenant, prepayment term       90 days
Debt instrument covenant, leverage ratio       2.00%
Estimated prepayment portion       $ 31,862
Letters of credit        
Debt        
Credit facility amount $ 5,000 $ 5,000 $ 5,000  
Term Notes        
Debt        
Face amount 160,000      
Periodic payment $ 2,000      
Minimum | Credit Agreement | LIBOR        
Debt        
Spread on variable rate basis (as a percent) 1.50% 1.50% 1.25%  
Maximum | Credit Agreement | LIBOR        
Debt        
Spread on variable rate basis (as a percent) 3.25% 3.25% 1.75%