Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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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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Balance Sheet Details - Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Restructuring charges	$ 5,340	$ 699
Severance and Related Benefits
Restructuring Reserve [Roll Forward]
Restructuring charges	5,300
March 2017 Restructuring
Restructuring Reserve [Roll Forward]
Restructuring charges			$ 4,200
March 2017 Restructuring \| Severance and Related Benefits
Restructuring Reserve [Roll Forward]
Balance at December 31, 2017	975
Restructuring charges	4,567
Cash payments	(1,501)
Balance at March 31, 2018	4,041		975
March 2017 Restructuring \| Facilities
Restructuring Reserve [Roll Forward]
Balance at December 31, 2017	442
Restructuring charges	773
Cash payments	(329)
Balance at March 31, 2018	$ 886		$ 442