Significant Accounting Policies - Accrued Receivable and Accrued Claims Payable (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Accrued receivables	$ 12.0	$ 16.0
Accrued claims payable	14.2	9.8
Unbilled receivables	$ 21.1	$ 8.5

Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

No definition available.

Name:	us-gaap_UnbilledReceivablesCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant