Reduction in Workforce

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- Definition

Restructuring Charges, Excluding Noncash Charges

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- Definition

Write-off of Fixed Assets

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

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.

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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.

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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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Amount of increase (decrease) in the restructuring reserve related to foreign currency translation (gain) loss and other increases (decreases).

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Restructuring Charges - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Percentage reduction in workforce	10.00%
Restructuring charges		$ 27,630	$ 0	$ 4,327
Restructuring charges, excluding noncash charges		23,021	0
Stock-based compensation expense		198,895	222,431	151,852
Adjustments for deferred rent		1,738
Restructuring reserve		3,467	217	765
Severance and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges, excluding noncash charges		21,529	0
Adjustments for deferred rent		0
Restructuring reserve		1,221	0	0
Facilities costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges, excluding noncash charges		1,492	0
Adjustments for deferred rent		1,738
Restructuring reserve		2,246	217	765
Restructuring
Restructuring Cost and Reserve [Line Items]
Fixed assets writeoff		3,500
Stock-based compensation expense		$ 1,144	$ 0	$ 0