Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Contractual obligation	$ 69.9	$ 55.5
Letters of credit, outstanding amount	$ 27.7	$ 19.7

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

No definition available.

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant