Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - Narrative (Details)

v3.19.3
Commitments and Contingencies - Narrative (Details)
$ in Millions
9 Months Ended 12 Months Ended
Sep. 30, 2019
USD ($)
contract
Dec. 31, 2018
USD ($)
Other Commitments [Line Items]    
Letters of credit outstanding, amount $ 10.7 $ 9.7
Purchase commitment $ 143.9  
Corporate office space | San Francisco, California and Denver, Colorado    
Other Commitments [Line Items]    
Operating lease agreements | contract 2  
Minimum | Corporate office space | San Francisco, California and Denver, Colorado    
Other Commitments [Line Items]    
Lease agreement terms 5 years  
Maximum | Corporate office space | San Francisco, California and Denver, Colorado    
Other Commitments [Line Items]    
Lease agreement terms 7 years  
Letter of Credit | Minimum    
Other Commitments [Line Items]    
Letter of credit, fee percentage 2.13% 2.50%
Letter of Credit | Maximum    
Other Commitments [Line Items]    
Letter of credit, fee percentage 3.25% 3.25%