LONG-TERM DEBT - Refinancing of Credit Agreement and Term B Borrowings (Details) - USD ($) $ in Thousands		3 Months Ended
	Mar. 06, 2018	Mar. 31, 2018	Dec. 31, 2017
Long-Term Debt
Outstanding amount of debt		$ 525,975	$ 460,956
Debt issuance costs		6,757
Debt call premium		$ 8,436
Credit Agreement
Long-Term Debt
Maximum borrowing capacity	$ 605,000
Weighted average interest rate		5.40%
Interest rate in excess of applicable rate upon acceleration and default ( as a percent)	2.00%
Credit Agreement | One-month LIBOR
Long-Term Debt
Interest rate margin (as a percent)	1.00%
Credit Agreement | Federal funds rate
Long-Term Debt
Interest rate margin (as a percent)	0.50%
Credit Agreement | Fiscal quarters ended June 30, 2018, September 30, 2018, December 31, 2018 and March 31, 2019
Long-Term Debt
Consolidated leverage ratio	5.00%
Credit Agreement | Fiscal quarters ended June 30, 2019 through March 31, 2020
Long-Term Debt
Consolidated leverage ratio	4.75%
Credit Agreement | Fiscal quarters ended June 30, 2020 through March 31, 2021
Long-Term Debt
Consolidated leverage ratio	4.50%
Credit Agreement | Fiscal quarters ended June 30, 2021 through March 31, 2022
Long-Term Debt
Consolidated leverage ratio	4.25%
Credit Agreement | Fiscal quarters ended June 30, 2022 and the last day of each fiscal quarter thereafter
Long-Term Debt
Consolidated leverage ratio	3.75%
Credit Agreement | Last day of any fiscal quarter
Long-Term Debt
Consolidated leverage ratio	2.75%
Credit Agreement | Term Loan
Long-Term Debt
Outstanding amount of debt	$ 505,000
Credit Agreement | Revolving Credit Facility
Long-Term Debt
Maximum borrowing capacity	100,000
Letters of credit outstanding amount	5,900
Increase in additional borrowing capacity	$ 125,000
Maximum leverage ratio to use maximum credit facility	3.80
Increase in margin(as a percent)	50.00%
Credit Agreement | Revolving Credit Facility | Minimum
Long-Term Debt
Unused commitment fee (as a percent)	0.375%
Credit Agreement | Revolving Credit Facility | Maximum
Long-Term Debt
Unused commitment fee (as a percent)	0.50%
Credit Agreement, dated March 6, 2018
Long-Term Debt
Proceeds from borrowing	$ 501,500
Debt issuance costs	6,800
Prior Credit Agreement, dated August 1, 2016
Long-Term Debt
Debt call premium	8,400
Unamortized discount and debt issuance costs expensed	$ 8,600
Prior Credit Agreement, dated June 17, 2013 | Revolving Credit Facility
Long-Term Debt
Outstanding amount of debt			$ 5,000