Net Income (Loss) per Share - Additional Information (Detail)	6 Months Ended
Jun. 30, 2016 shares $ / shares	Dec. 31, 2015
Six Percent Tangible Equity Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate percentage	6.00%
Convertible Debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate percentage	3.75%	3.75%
Conversion price of convertible notes \| $ / shares	$ 24.49
Minimum \| Six Percent Tangible Equity Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Debt and equity instruments, shares to be Issued (in shares)	6,547,800
Maximum \| Six Percent Tangible Equity Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Debt and equity instruments, shares to be Issued (in shares)	7,857,000
Six Percent Tangible Equity Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Average interest rate	6.00%	6.00%

Represents the shares to be issued for our debt and equity instruments

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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.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

Contractual interest rate for funds borrowed, under the debt 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Weighted average interest rate of long-term debt outstanding.

+ References

No definition available.

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