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

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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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=6451184&loc=d3e28551-108399

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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
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.

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Data Type:	xbrli:stringItemType
Balance Type:	na
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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
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Period Type:	duration

Debt - Schedule of the Company's Debt (Parenthetical) (Detail)			12 Months Ended
	Mar. 20, 2014	Mar. 13, 2012	Dec. 31, 2015	Feb. 29, 2016	Dec. 31, 2014
5.50% Senior Notes Due May 15, 2015
Debt Instrument [Line Items]
Interest rate			5.50%
Maturity date			May 15, 2015
8.60% Senior Notes Due August 15, 2016
Debt Instrument [Line Items]
Interest rate			8.60%
Maturity date			Aug. 15, 2016
6.125% Senior Notes Due January 15, 2017
Debt Instrument [Line Items]
Interest rate			6.125%
Maturity date			Jan. 15, 2017
7.25% Senior Notes Due May 15, 2018
Debt Instrument [Line Items]
Interest rate	7.25%		7.25%
Maturity date	May 15, 2018		May 15, 2018
11.25% Senior Notes Due February 1, 2019
Debt Instrument [Line Items]
Interest rate			11.25%
Maturity date			Feb. 01, 2019
Effective interest rate			12.75%		12.75%
11.25% Senior Notes Due February 1, 2019 \| Scenario Forecast
Debt Instrument [Line Items]
Effective interest rate				13.00%
8.25% Senior Notes Due March 15, 2019
Debt Instrument [Line Items]
Interest rate	8.25%	8.25%	8.25%		8.25%
Maturity date	Mar. 15, 2019	Mar. 15, 2019	Mar. 15, 2019
7.625% Senior Notes Due June 15, 2020
Debt Instrument [Line Items]
Interest rate	7.625%		7.625%
Maturity date	Jun. 15, 2020		Jun. 15, 2020
7.875% Senior Notes Due March 15, 2021
Debt Instrument [Line Items]
Interest rate			7.875%
Maturity date			Mar. 15, 2021
8.875% Debentures Due April 15, 2021
Debt Instrument [Line Items]
Interest rate			8.875%
Maturity date			Apr. 15, 2021
7.00% Senior Notes Due February 15, 2022
Debt Instrument [Line Items]
Interest rate			7.00%
Maturity date			Feb. 15, 2022
6.50% Senior Notes Due November 15, 2023
Debt Instrument [Line Items]
Interest rate			6.50%
Maturity date			Nov. 15, 2023
6.00% Senior Notes Due due April 1, 2024
Debt Instrument [Line Items]
Interest rate			6.00%
Maturity date			Apr. 01, 2024
6.625% Debentures Due April 15, 2029
Debt Instrument [Line Items]
Interest rate			6.625%
Maturity date			Apr. 15, 2029
8.820% Debentures Due April 15, 2031
Debt Instrument [Line Items]
Interest rate			8.82%
Maturity date			Apr. 15, 2031