Achieved senior secured leverage ratio.

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- Definition

Achieved total leverage ratio.

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No definition available.

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- Definition

Additional interest rate reduction basis points resulting from net leverage ratio below minimum.

+ References

No definition available.

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- Definition

Commitment fee reduction resulting from total leverage ratio below minimum.

+ References

No definition available.

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- Definition

Debt instrument floor rate.

+ References

No definition available.

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- Definition

Decrease in debt instrument basis spread on variable rate.

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No definition available.

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- Definition

Interest rate reduction basis points resulting from total leverage ratio below minimum.

+ References

No definition available.

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- Definition

Maximum amount of letters of credit commitments available under the revolving credit facility.

+ References

No definition available.

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- Definition

Maximum senior secured leverage ratio.

+ References

No definition available.

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- Definition

Required senior secured leverage ratio.

+ References

No definition available.

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- Definition

Total leverage ratio threshold for commitment fee reduction.

+ References

No definition available.

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- Definition

Total leverage ratio threshold for rate reduction.

+ References

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.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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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.

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No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Amount of the total principal payments made during the annual reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

+ Details

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- 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

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- Definition

Amount of the required periodic payment applied to principal.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

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-SubTopic 10
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-Paragraph 15
-Subparagraph (e)
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DEBT - Senior Secured Credit Facility (Detail)		1 Months Ended			12 Months Ended
DEBT - Senior Secured Credit Facility (Detail)	Dec. 31, 2016	May 31, 2018 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Aug. 31, 2017 USD ($)
Debt Instrument [Line Items]
Total leverage ratio					2.05
Revolving Credit Facility, variable, due 2021
Debt Instrument [Line Items]
Maximum revolving credit facility						$ 550,000,000	$ 450,000,000
Maximum amount of letters of credit commitments available under the revolving credit facility					$ 75,000,000
Available revolving credit facility					533,000,000
Letters of Credit					17,000,000
Amount outstanding					$ 0
Basis point reduction to applicable margin, resulting from total leverage ratio below minimum					0.25%
Basis point reduction to commitment fee, resulting from total leverage ratio below minimum					0.125%
Additional basis point reduction to applicable margin, resulting from total leverage ratio below minimum					0.25%
Revolving Credit Facility, variable, due 2021 \| LIBOR
Debt Instrument [Line Items]
Applicable margin over base rate					1.75%
Revolving Credit Facility, variable, due 2021 \| greater of the prime lending rate or federal funds
Debt Instrument [Line Items]
Applicable margin over base rate					0.50%
Revolving Credit Facility, variable, due 2021 \| greater of the prime lending rate or federal funds \| Minimum
Debt Instrument [Line Items]
Applicable margin over base rate					0.75%
Debt instrument, floor rate					1.75%
Senior Secured Credit Facility
Debt Instrument [Line Items]
Required senior secured leverage ratio					5.50
Achieved senior secured leverage ratio					0.81
Senior secured leverage ratio for applicable margin reduction					4.00
Total leverage ratio for applicable margin reduction					4.00
Total leverage ratio for commitment fee reduction					3.50
Senior Secured Credit Facility Term B-3 Loan, variable, due 2022
Debt Instrument [Line Items]
Change in applicable margin over base rate			0.25%	0.50%
Applicable margin over base rate					0.50%
Debt financing fees			$ 1,000,000	$ 1,000,000
Debt instrument effective interest rate					4.26%
Principal payments on term loans					$ 3,000,000
Voluntary prepayments of principal amount		$ 25,000,000
Senior Secured Credit Facility Term B-3 Loan, variable, due 2022 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Applicable margin over base rate					1.75%
Senior Secured Credit Facility Term B-3 Loan, variable, due 2022 \| greater of the prime lending rate or federal funds
Debt Instrument [Line Items]
Applicable margin over base rate					1.00%
Senior Secured Credit Facility Term B-3 Loan, variable, due 2022 \| greater of the prime lending rate or federal funds \| Minimum
Debt Instrument [Line Items]
Applicable margin over base rate					0.75%
Debt instrument, floor rate	1.75%			1.00%