Commitments and Contingencies - Restructuring Activities and Sale of Guangzhou Factory (Details) ¥ in Millions, $ in Millions		12 Months Ended
Sep. 26, 2016 CNY (¥)	Dec. 31, 2016 USD ($)
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Guangzhou Factory
Restructuring Cost and Reserve [Line Items]
Consideration	¥ 320	$ 46.0
Period to cease operations (up to)	24 months
Expected term of completion	28 months
Escrow deposit as percentage of purchase price	10.00%
Employee Severance \| Manufacturing Activities Transition
Restructuring Cost and Reserve [Line Items]
Additional restructuring expenses related to be incurred		7.0
Employee Severance \| Manufacturing Activities Transition \| Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring expenses		4.5
Employee Severance \| Manufacturing Activities Transition \| Employee-related Liabilities, Current
Restructuring Cost and Reserve [Line Items]
Unpaid restructuring costs		$ 2.7

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Amount of expected cost remaining for the specified restructuring cost.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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