Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Additional Information (Details)

v3.10.0.1
Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Disaggregation of Revenue [Line Items]      
Contract period (or less) 1 year    
Activation fee revenue recognition period 1 month    
Data trial contract period 5 years    
Other Income and Expenses [Abstract]      
Advertising expense $ 266,935 $ 262,701 $ 226,969
Engineering, design and development 123,219 112,427 82,146
Engineering, Design and Development      
Other Income and Expenses [Abstract]      
Engineering, design and development $ 105,975 $ 96,917 $ 69,025
Minimum      
Disaggregation of Revenue [Line Items]      
Data trial contract period 3 years    
Maximum      
Disaggregation of Revenue [Line Items]      
Percent of deferred revenue related to long-term contracts 10.00%    
Subscription prepayment period 3 years    
Prepaid Vehicle Subscriptions | Minimum      
Disaggregation of Revenue [Line Items]      
Contract period (or less) 3 months    
Prepaid Vehicle Subscriptions | Maximum      
Disaggregation of Revenue [Line Items]      
Contract period (or less) 12 months