XML 87 R75.htm IDEA: XBRL DOCUMENT v3.8.0.1
Debt - Additional Information (Detail)
$ in Millions
3 Months Ended
Mar. 31, 2018
USD ($)
Debt Narrative Detail Information  
Tax Cuts and Jobs Act of 2017, Accounting Complete false
Letters of Credit Outstanding, Amount $ 2.1
Amount Outsanding on Credit Facility 0.0
Northwind Holdings LLC  
Debt Narrative Detail Information  
Principal Payments on Long-term Debt $ 15.0