Contract Liabilities and Other Disclosures (Tables)

6 Months Ended

Jun. 30, 2020

Contract Liabilities And Other Disclosures [Abstract]

Schedule of contract related balances

	Accounts Receivable		Unbilled Accounts Receivable		Deferred Income			Customer Prepayments and Deposits
	(in millions)
At June 30, 2020	$	19.7	$	7.4	$	(24.0	)	$	(0.9	)
At December 31, 2019	$	24.5	$	15.3	$	(27.8	)	$	(1.9	)
At December 31, 2018	$	11.5	$	11.0	$	(32.0	)	$	(3.6	)