Derivative Instruments and Hedging Activities-By Balance Sheet Location (Details) - Interest Rate Swap - USD ($)
$ in Thousands
Sep. 30, 2016
Dec. 31, 2015
Derivative [Line Items]    
Total fair value $ 18,691 $ 13,483
Other current liabilities    
Derivative [Line Items]    
Total fair value 4,546 3,914
Other noncurrent liabilities    
Derivative [Line Items]    
Total fair value $ 14,145 $ 9,569