Annual report pursuant to Section 13 and 15(d)

Employee Benefit Plans (Details)

v3.8.0.1
Employee Benefit Plans (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Employer cash contribution   $ 1.0 $ 0.8 $ 1.1
Skyhook | Liberty 401k Plan        
Company matching contribution (as a percent)   100.00%    
Employee salary eligible for matching contributions (as a percent) 10.00%