Percentage of aggregate principle which may be redeemed at any time at a specified price.

No definition available.

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- Definition

Percentage premium which may be required for repayment if the Company undergoes a change in control.

+ References

No definition available.

+ Details

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- Definition

Debt instrument redemption, percentage of debt outstanding, post redemption.

+ References

No definition available.

+ Details

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- Definition

Line of credit facility amended and restated date.

+ References

No definition available.

+ Details

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- Definition

Ratio of indebtedness to net capital minimum.

+ References

No definition available.

+ Details

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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

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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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.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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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.

+ Details

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

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

- Definition

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

+ References

+ Details

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

- Definition

The cash inflow from bank borrowing during the year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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Long-term Debt - Additional Information (Detail)						9 Months Ended
Long-term Debt - Additional Information (Detail)	May 15, 2017 USD ($)	Jan. 28, 2016 USD ($)	Jan. 10, 2014 USD ($)	Oct. 30, 2012 USD ($)	Feb. 09, 2012 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016
Debt Instrument [Line Items]
Amended and restated date	May 15, 2017
Proceeds received from senior credit facility term loans						$ 450,000,000	$ 300,000,000
Outstanding revolving credit facility						90,000,000
Remaining borrowing capacity under revolving credit facility						346,909,000
Letter of Credit [Member]
Debt Instrument [Line Items]
Letter of credit outstanding balance						$ 13,091,000
Senior Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing limit of incremental loan facility	$ 450,000,000
Debt instrument maturity date	May 15, 2022
Term A Loan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing limit of incremental loan facility	$ 450,000,000
Debt instrument maturity date	May 15, 2022
Proceeds received from senior credit facility term loans	$ 450,000,000
Term A Loan Facility [Member] \| LIBO Rate [Member]
Debt Instrument [Line Items]
Adjusted Rate	1.75%
Ratio of indebtedness to net capital one	3.25
Ratio of indebtedness to net capital minimum	1
Term A Loan Facility [Member] \| LIBO Rate [Member] \| Debt Ratio Less Than Four Point Two Five [Member]
Debt Instrument [Line Items]
Adjusted Rate	1.50%
Term A Loan Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Adjusted Rate	0.75%
Ratio of indebtedness to net capital one	3.25
Ratio of indebtedness to net capital minimum	1
Term A Loan Facility [Member] \| Base Rate [Member] \| Debt Ratio Less Than Four Point Two Five [Member]
Debt Instrument [Line Items]
Adjusted Rate	0.50%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument maturity date						May 15, 2022
Revolving Credit Facility [Member] \| LIBO Rate [Member]
Debt Instrument [Line Items]
Adjusted Rate	1.75%
Ratio of indebtedness to net capital one	3.25
Ratio of indebtedness to net capital minimum	1
Revolving Credit Facility [Member] \| LIBO Rate [Member] \| Debt Ratio Less Than Four Point Two Five [Member]
Debt Instrument [Line Items]
Adjusted Rate	1.50%
Revolving Credit Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Adjusted Rate	0.75%
Ratio of indebtedness to net capital one	3.25
Ratio of indebtedness to net capital minimum	1
Revolving Credit Facility [Member] \| Base Rate [Member] \| Debt Ratio Less Than Four Point Two Five [Member]
Debt Instrument [Line Items]
Adjusted Rate	0.50%
5 7/8% Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes					5.875%	5.875%		5.875%
Aggregate principal amount of debt issued					$ 500,000,000
Net proceeds from the issuance of debt					$ 489,000,000
Redemption price percentage of the principal amount to be purchased					101.00%
5% Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes				5.00%		5.00%		5.00%
Aggregate principal amount of debt issued				$ 535,000,000
Net proceeds from the issuance of debt				$ 527,100,000
Redemption price percentage of the principal amount to be purchased				101.00%
Redemption percentage equal to principal amount include aggregate premium				100.00%
5 3/8% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes			5.375%			5.375%		5.375%
Aggregate principal amount of debt issued			$ 510,000,000
Net proceeds from the issuance of debt			$ 502,300,000
Redemption price percentage of the principal amount to be purchased			101.00%
5 3/8% Senior Notes [Member] \| Prior to January 15, 2019 [Member]
Debt Instrument [Line Items]
Redemption percentage equal to principal amount include aggregate premium			100.00%
5 3/4% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes		5.75%				5.75%		5.75%
Aggregate principal amount of debt issued		$ 400,000,000
Net proceeds from the issuance of debt		$ 394,500,000
Redemption price percentage of the principal amount to be purchased		101.00%
5 3/4% Senior Notes [Member] \| Prior to February 1, 2019 [Member]
Debt Instrument [Line Items]
Redemption percentage of aggregate principal amount of senior notes		35.00%
Additional redeemed percentage of aggregate principal amount		105.75%
Redemption percentage of issued notes which remain outstanding		65.00%
5 3/4% Senior Notes [Member] \| Prior to February 1, 2021 [Member]
Debt Instrument [Line Items]
Additional redeemed percentage of aggregate principal amount		100.00%