Business Combination - Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed (Details) - USD ($)
$ in Thousands
Aug. 31, 2016
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Assets acquired and liabilities assumed        
Goodwill   $ 185,138 $ 163,154 $ 163,154
Runbook Company B.V.        
Business Acquisition [Line Items]        
Total cash consideration to selling shareholders $ 34,052      
Assets acquired and liabilities assumed        
Cash and cash equivalents 2,564      
Accounts receivable 2,518      
Prepaid expenses and other current assets 718      
Property and equipment 427      
Intangible assets 9,790      
Accounts payable (285)      
Accrued expenses and other current liabilities (376)      
Deferred revenue (501)      
Net deferred income tax liabilities (2,787)      
Net assets 12,068      
Goodwill $ 21,984