Net Income (Loss) per Share - Additional Information (Detail) - $ / shares	1 Months Ended
Dec. 31, 2016	Jun. 30, 2017
Six Percent Tangible Equity Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Interest rate percentage		6.00%
Six Percent Tangible Equity Units \| Maximum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Settlement of tangible equity units, shares	7,857,000
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		$ 24.49

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.

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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-Subparagraph (b)
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Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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