Basis of Presentation - Additional Information (Details) $ in Thousands	2 Months Ended	3 Months Ended		6 Months Ended		8 Months Ended	12 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) segment	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reporting segments | segment				1
Unbilled receivables	$ 1,900	$ 1,900		$ 1,900		$ 2,700	$ 2,700
Decrease in deferred revenue		(400)		(700)
Deferred revenue, additional invoicing		700		1,500
Deferred revenue recognized		1,000		2,200
Deferred revenue recognized that was included in the balance at the beginning of the period		300		1,000
Deferred revenue	1,600	1,600		1,600
Deferred revenue, long-term	30	30		30
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in tax benefit related to tax adjustment of acquired valuation allowance		86	$ (12)	$ 86	$ (17)
PHS
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in goodwill after measurement period related to tax adjustment of acquired valuation allowance						$ 1,600
PHS | Immaterial Error Correction
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in goodwill after measurement period related to tax adjustment of acquired valuation allowance	100	$ 100
Increase in tax benefit related to tax adjustment of acquired valuation allowance	$ 100						$ 100