Applicable Margin Rate

No definition available.

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- Definition

Line of Credit, Utilization Fee Rate

+ References

No definition available.

+ Details

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- Definition

Tangible Shareholder Equity

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Aggregate amount of interest expense on all borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.7,8)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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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

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

- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Balance Type:	credit
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- Definition

The effective interest rate during the reporting period.

+ References

+ 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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fair value of notes issued in noncash investing and financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

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-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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-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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Article 5

-Subsection 19, 20, 22

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Long-Term Debt and Notes Payable - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				3 Months Ended			3 Months Ended					3 Months Ended			1 Months Ended
	Mar. 31, 2014	Mar. 31, 2014 Financial Letter of Credit [Member]	Mar. 31, 2014 Performance Letters of Credit [Member]	Mar. 31, 2014 Commitments [Member]	Mar. 31, 2014 Senior Notes [Member]	Mar. 31, 2014 Eurodollar rate [Member]	Mar. 31, 2014 Base Rate [Member]	Mar. 31, 2014 Letter of Credit Facility [Member]	Mar. 31, 2014 Term Loan [Member]	Mar. 31, 2014 Revolving Credit Facility [Member]	Feb. 28, 2014 Revolving Credit Facility [Member]	Dec. 31, 2013 Revolving Credit Facility [Member]	Jun. 30, 2014 Revolving Credit Facility [Member] Scenario, Forecast [Member]	Mar. 31, 2014 Former Credit Agreement [Member]	Apr. 30, 2014 Subsequent [Member]	Apr. 30, 2014 Subsequent [Member] Senior Notes [Member]	Apr. 30, 2014 Subsequent [Member] Letter of Credit Facility [Member]	Apr. 30, 2014 Subsequent [Member] Term Loan [Member]	Apr. 30, 2014 Subsequent [Member] Tangible Equity Units [Member]
Debt Instrument [Line Items]
Letter of credit, first lien															$ 950.0		$ 400.0	$ 300.0
Revolving credit borrowings outstanding										250.0		0
Letters of credit outstanding	376.0									376.0	109.0	214.3
Issue of second-lien seven-year senior secured notes					500.0											500.0
Issue of tangible equity units																			287.5
Tangible equity units, aggregate principal amount																47.5
Unamortized issuance fees recognized as expenses													28.0
Line of credit aggregate borrowing capacity								600.0		950.0				250.0
Average outstanding borrowings under the Former Credit Agreement														$ 165.0
Average interest rate														3.45%
Applicable margin						2.00%	1.00%
Letter of credit fee		2.00%	1.00%	0.30%
Debt instrument maturity date	Apr. 01, 2017				May 01, 2021			Apr. 16, 2017	Apr. 16, 2019