NOTES PAYABLE AND COMMERCIAL BANK FINANCING - Stated and Weighted Average Effective Interest Rates (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Term Loan \| Term Loan A-2
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	4.12%	3.30%
Term Loan \| Term Loan A-2 \| Minimum
Debt Instrument [Line Items]
Unrestricted cash first lien indebtedness ratio	1.5
Term Loan \| Term Loan A-2 \| LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	2.25%
Term Loan \| Term Loan A-2 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Interest rate margin (as a percent)	2.00%
Term Loan \| Term Loan B
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	4.34%	3.32%
Term Loan \| Term Loan B \| LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	2.25%
Senior Notes \| 5.375% Senior Unsecured Notes due 2021
Debt Instrument [Line Items]
Interest rate (as a percent)	5.38%	5.375%
Weighted average effective interest rate (as a percent)	5.58%	5.58%
Senior Notes \| 6.125% Senior Unsecured Notes due 2022
Debt Instrument [Line Items]
Interest rate (as a percent)	6.13%	6.125%
Weighted average effective interest rate (as a percent)	6.31%	6.31%
Senior Notes \| 5.625% Senior Unsecured Notes due 2024
Debt Instrument [Line Items]
Interest rate (as a percent)	5.63%
Weighted average effective interest rate (as a percent)	5.83%	5.83%
Senior Notes \| 5.875% Senior Unsecured Notes due 2026
Debt Instrument [Line Items]
Interest rate (as a percent)	5.88%	5.875%
Weighted average effective interest rate (as a percent)	6.09%	6.09%
Senior Notes \| 5.125% Senior Unsecured Notes due 2027
Debt Instrument [Line Items]
Interest rate (as a percent)	5.13%	5.125%
Weighted average effective interest rate (as a percent)	5.33%	5.33%
Revolving Credit Facility \| Line of credit
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)	0.00%	0.00%
Maximum borrowing capacity	$ 485,200,000
Aggregate borrowings outstanding	$ 0
Revolving Credit Facility \| Line of credit \| Minimum
Debt Instrument [Line Items]
Undrawn commitments fees (as a percent)	0.25%
Revolving Credit Facility \| Line of credit \| Maximum
Debt Instrument [Line Items]
Unrestricted cash first lien indebtedness ratio	3.0
Undrawn commitments fees (as a percent)	0.50%
Revolving Credit Facility \| Line of credit \| LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	2.00%
Letter of Credit \| Line of credit
Debt Instrument [Line Items]
Aggregate borrowings outstanding	$ 700,000	$ 800,000

Cash First Lien Indebtedness Ratio, Threshold In Which Commitment Fee Is Incurred

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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