Net Income (Loss) Per Share - Additional Information (Detail)	12 Months Ended
Dec. 31, 2019 $ / shares shares
Company average common stock price for a given period exceeds conversion price $5.75 for 2020 Notes [Member] \| Convertible Note due 2020 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares \| shares	7,962,609
Debt Instrument, Convertible, Conversion Price \| $ / shares	$ 5.75
Company average common stock price for a given period exceeds conversion price $8.66 for 2024 Notes [Member] \| Convertible Note due 2024 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares \| shares	13,337,182
Debt Instrument, Convertible, Conversion Price \| $ / shares	$ 8.66

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of contingently issuable shares. Contingently issuable shares are those shares that are issuable for little or no cash contingent on certain conditions being met.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 55
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e2626-109256

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 48
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e2538-109256

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Balance Type:	na
Period Type:	duration