SCHEDULE I - CONDENSED FINANCIAL INFORMATION (Details 4) - USD ($)	Dec. 31, 2017	Nov. 18, 2015	Jul. 31, 2015
Term Loan
Line of Credit Facility [Line Items]
Face amount			$ 425,000,000
Revolving loan
Line of Credit Facility [Line Items]
Maximum borrowing available			25,000,000
Letter-of-credit sub-facility
Line of Credit Facility [Line Items]
Maximum borrowing available			$ 10,000,000
Credit Facility
Schedule of principal repayments under the Term Loan
2018	$ 7,926,000
2019	5,322,000
2020	4,250,000
2021	401,625,000
2022	0
Cap on dividends paid and shares and warrants that can be repurchased per fiscal year under restrictive covenants	$ 12,000,000	$ 12,000,000