BASIC AND DILUTED EARNINGS PER COMMON SHARE - Components of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014
Numerator:
(Loss) income from continuing operations, net of taxes	$ (33.9)	$ (4.5)	$ 10.8	$ 10.6	$ 26.2	$ 7.9	$ 26.0	$ (0.8)	$ (17.0)	$ 59.3		$ 39.6
(Loss) income from discontinued operations, net of taxes	(2.6)	(0.2)	(2.5)	0.4	(1.4)	(1.7)	0.0	(0.1)	(4.9)	(3.2)		1.3
Net (loss) income	$ (36.5)	$ (4.7)	$ 8.3	$ 11.0	$ 24.8	$ 6.2	$ 26.0	$ (0.9)	$ (21.9)	$ 56.1	[1]	$ 40.9	[1]
Denominator:
Weighted average common shares outstanding - Basic (shares)									52,504,196	52,431,193		52,359,897
Effect of dilutive restricted stock (shares)									0	160,352		64,042
Weighted average common shares outstanding - Diluted (shares)									52,504,196	52,591,545		52,423,939
Basic (loss) earnings per common share:
Continuing operations (usd per share)	$ (0.65)	$ (0.09)	$ 0.21	$ 0.20	$ 0.50	$ 0.15	$ 0.50	$ (0.02)	$ (0.33)	$ 1.13		$ 0.76
Discontinued operations (usd per share)	(0.05)	0.00	(0.05)	0.01	(0.03)	(0.03)	0.00	0.00	(0.09)	(0.06)		0.02
Net (loss) income (usd per share)	(0.70)	(0.09)	0.16	0.21	0.47	0.12	0.50	(0.02)	(0.42)	1.07		0.78
Diluted (loss) earnings per common share:
Continuing operations (usd per share)	(0.65)	(0.09)	0.21	0.20	0.50	0.15	0.49	(0.02)	(0.33)	1.13		0.76
Discontinued operations (usd per share)	(0.05)	0.00	(0.05)	0.01	(0.03)	(0.03)	0.00	0.00	(0.09)	(0.06)		0.02
Net (loss) income (usd per share)	$ (0.70)	$ (0.09)	$ 0.16	$ 0.21	$ 0.47	$ 0.12	$ 0.49	$ (0.02)	$ (0.42)	$ 1.07		$ 0.78
Restricted Stock [Member]
Diluted (loss) earnings per common share:
Unvested restricted stock awards under the Stock Plan									109,481	0		0

[1] Adjusted as a result of the adoption of certain accounting pronouncements beginning on January 1, 2016. See Note 1, "Description of Business and Summary of Significant Accounting Policies - Recently Adopted Accounting Pronouncements," for details of these adjustments.