PREFERRED STOCK - Additional Information (Detail) $ / shares in Units, $ in Millions			1 Months Ended			12 Months Ended
	Sep. 14, 2018 shares	Sep. 15, 2015 USD ($) $ / shares shares	Aug. 31, 2018 shares	May 31, 2018 shares	Feb. 28, 2018 shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($)	Dec. 31, 2019 $ / shares shares
Class of Stock [Line Items]
Preferred stock, authorized (in shares)						1,000,000.0		1,000,000.0
Preferred stock, issued (in shares)	638,190					0.0		0.0
Preferred stock, outstanding (in shares)						0.0		0.0
Depositary shares (in shares)		7,700,000
Each depository share represents number of preferred shares		0.1
Preferred stock, dividend rate		5.25%
Preferred stock, par value (in dollars per share) | $ / shares		$ 0.01				$ 0.01		$ 0.01
Gross proceeds from issuance of preferred stock | $		$ 770.0
Conversion of preferred stock to common stock conversion ratio	7.3394
Conversion of preferred stock to common stock, (in shares)	4,700,000
Preferred stock, liquidation preference (in dollars per share) | $ / shares		$ 1,000
Depositary Shares, Liquidation Preference Per Share | $ / shares		100.00
Dividends paid on mandatory convertible preferred shareholders | $						$ 25.5	$ 36.3
Increase to retained earnings on repurchase of depository shares | $						$ 16.9	$ 17.3
Depositary shares repurchased during period (in shares)			50,000	150,000	151,900	351,900
Depository shares equivalent to preferred stock units (in shares)						35,190
Preferred Stock
Class of Stock [Line Items]
Issuance of preferred stock (in dollars per share) | $ / shares		$ 100.00
Conversion of preferred stock to common stock, (in shares)						(600,000)