CAPITAL STOCK - Additional Information - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity, Class of Treasury Stock [Line Items]
Aggregate cost of repurchase	$ 61.0	$ 83.4
Number of shares repurchased under settlement of employee tax withholding obligations	0.1	0.2
Shares repurchased aggregate value under settlement of employee tax withholding obligations	$ 11.0	$ 10.2
2006 Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase of shares of common stock	1.4
Aggregate cost of repurchase		$ 61.9
2019 Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Share repurchase program	$ 500.0
Repurchase of shares of common stock	0.6
Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase of shares of common stock		1.7
Aggregate cost of repurchase	$ 50.0	$ 73.2