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Workforce Reduction - General Information (Details) $ in Millions			3 Months Ended
	Jun. 27, 2018 USD ($) employee	Jan. 30, 2018 employee	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)
Reduction in Field-based Workforce, January 30, 2018
Workforce Reduction
Number of employees eliminated \| employee		60
Employee severance, benefits and related costs				$ 2.4
Reduction in Headquarter-based Workforce, June 27, 2018
Workforce Reduction
Number of employees expected to be eliminated \| employee	40
Expected cost	$ 5.3
Employee severance, benefits and related costs			$ 2.4