Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Fair Value, Liabilities Measured on Recurring Basis

Financial liabilities that are measured at fair value on a recurring basis were as follows:

($ in millions)	Quoted Prices in Active Market (Level 1)	Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)	Total
December 31, 2020
Deferred compensation liabilities	—	$	3.7	—	$	3.7
December 31, 2019
Deferred compensation liabilities	—	$	14.7	—	$	14.7