Products and Services Revenues - Additional Information, Performance Obligation (Details) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01	3 Months Ended
	Mar. 31, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, percentage	98.00%
Expected timing of satisfaction, period	2 years 9 months