Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

 Our financial assets and liabilities measured at fair value on a recurring basis were categorized as follows:

	December 31, 2020
	Level 1		Level 2			Level 3		Total
	(Dollars in millions)
Assets
Available for sale customer trust funds assets	$	—	$	1,719.1	(a)	$	—	$	1,719.1
Total assets measured at fair value	$	—	$	1,719.1		$	—	$	1,719.1

	December 31, 2019
	Level 1		Level 2			Level 3		Total
	(Dollars in millions)
Assets
Available for sale customer trust funds assets	$	—	$	1,826.8	(a)	$	—	$	1,826.8
Total assets measured at fair value	$	—	$	1,826.8		$	—	$	1,826.8

(a) Fair value is based on inputs that are observable for the asset or liability, other than quoted prices.