Debt Instrument Aggregate Principal Amount

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument maturity year.

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Redemption Amount

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Redemption Price per Aggregate Principal Amount

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Line of credit facility expected increase amount.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility Fronting Fee Percentage

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility Maximum Leverage Percentage

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Period of prior notice required for redemption of notes.

+ References

No definition available.

+ Details

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

- 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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Period Type:	duration

- 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

End date of debt instrument redemption period, in CCYY-MM-DD format.

+ 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=6479336&loc=d3e64711-112823

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- Definition

Start date of debt instrument redemption period, in CCYY-MM-DD format.

+ References

+ Details

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Period Type:	duration

- Definition

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

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 50
-Section 40
-Paragraph 2
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+ Details

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

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
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
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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

- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
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+ Details

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

- Definition

The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

+ References

No definition available.

+ Details

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

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

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
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- Details

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- Details

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Long-Term Debt - Additional Information (Detail) - USD ($)				3 Months Ended	12 Months Ended
	Sep. 23, 2015	Aug. 28, 2015	Aug. 14, 2015	Sep. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Loss on early extinguishment of debt				$ (19,589,000)		$ (19,589,000)
Debt issue costs included in other assets					$ 4,472,000	5,228,000
Former Credit Facility
Debt Instrument [Line Items]
Senior secured revolving line of credit					350,000,000
2015 Credit Facility
Debt Instrument [Line Items]
Senior secured revolving line of credit					$ 550,000,000
Line of credit, maturity date					Sep. 26, 2020
Senior Bank Credit Facility
Debt Instrument [Line Items]
Borrowing interest rate description					The applicable margin will fluctuate between 1.375% per annum and 2.00% per annum, in the case of LIBOR borrowings, or between 0.375% per annum and 1.00% per annum, in the case of base rate borrowings, in each case, based upon the Company’s Consolidated Total Leverage Ratio (as defined in the 2015 Credit Agreement) at such time.
Senior secured revolving line of credit					$ 100,000,000
Leverage ratio					350.00%
Credit facility					$ 70,000,000	200,000,000
Letters of Credit Outstanding, Amount					700,000
Debt issue costs included in other assets					$ 4,300,000	$ 5,500,000	$ 2,800,000
Minimum \| Senior Bank Credit Facility
Debt Instrument [Line Items]
Line of credit, commitment fees on unused borrowing capacity					0.25%
Line of credit, fronting fees					1.375%
Minimum \| Senior Bank Credit Facility \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Revolving Credit Facility, percentage points added to the reference rate					1.375%
Minimum \| Senior Bank Credit Facility \| Base Rate
Debt Instrument [Line Items]
Revolving Credit Facility, percentage points added to the reference rate					0.375%
Maximum \| Senior Bank Credit Facility
Debt Instrument [Line Items]
Line of credit, commitment fees on unused borrowing capacity					0.35%
Line of credit, fronting fees					2.00%
Maximum \| Senior Bank Credit Facility \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Revolving Credit Facility, percentage points added to the reference rate					2.00%
Maximum \| Senior Bank Credit Facility \| Base Rate
Debt Instrument [Line Items]
Revolving Credit Facility, percentage points added to the reference rate					1.00%
6.0% Senior Notes Due 2022
Debt Instrument [Line Items]
Interest percentage					6.00%	6.00%
Debt maturity period					2022	2022
Debt redemption period start date					Nov. 15, 2022
Redemption price percentage					100.00%
Debt issue costs					$ 7,600,000
6.0% Senior Notes Due 2022 \| Minimum
Debt Instrument [Line Items]
Number of days prior notice required for redemption of notes					30 days
6.0% Senior Notes Due 2022 \| Maximum
Debt Instrument [Line Items]
Number of days prior notice required for redemption of notes					60 days
6 3/4 % Senior Notes Due 2020
Debt Instrument [Line Items]
Interest percentage					6.75%
Debt maturity period					2020
Debt redemption period start date	Sep. 01, 2015
Debt redemption price for each $1000 principal amount			$ 1,037.88
Debt aggregate principal amount			$ 1,000
Debt maturity date			Aug. 27, 2015
Repayment of debt		$ 192,900,000
Debt redemption amount	$ 207,100,000
Debt redemption period end date	Oct. 01, 2015
Loss on early extinguishment of debt						$ (19,600,000)
Write-off of unamortized deferred financing costs						4,900,000
Redemption premium						$ 14,300,000
6 3/4 % Senior Notes Due 2020 Tender Offer
Debt Instrument [Line Items]
Debt redemption price for each $1000 principal amount			$ 1,033.75
Debt aggregate principal amount			$ 1,000