Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Dec. 31, 2018	$ 1,848.2	$ 0.1	$ 1,687.1	$ 232.6	$ (71.6)
Beginning balance (in shares) at Dec. 31, 2018		64,200,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation and vesting of restricted stock	9.6		9.6
Net income/(loss)	127.2			127.2
Dividends declared	(44.4)			(44.4)
Total comprehensive loss, net of tax	(18.3)				(18.3)
Ending balance at Dec. 31, 2019	1,922.3	$ 0.1	1,696.7	315.4	(89.9)
Ending balance (in shares) at Dec. 31, 2019		64,200,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation and vesting of restricted stock	9.3		9.3
Stock-based compensation and vesting of restricted stock (in shares)		500,000
Net income/(loss)	(25.5)			(25.5)
Dividends declared	(20.4)			(20.4)
Total comprehensive loss, net of tax	111.0				111.0
Ending balance at Dec. 31, 2020	1,996.7	$ 0.1	1,706.0	269.5	21.1
Ending balance (in shares) at Dec. 31, 2020		64,700,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation and vesting of restricted stock	10.2		10.2
Stock-based compensation and vesting of restricted stock (in shares)		100,000
Issuance of common stock upon exercise of options	$ 2.2		2.2
Issuance of common stock upon exercise of options (in shares)	72,200	100,000
Net income/(loss)	$ 27.7			27.7
Dividends declared	(19.6)			(19.6)
Total comprehensive loss, net of tax	(32.1)				(32.1)
Ending balance at Dec. 31, 2021	$ 1,985.1	$ 0.1	$ 1,718.4	$ 277.6	$ (11.0)
Ending balance (in shares) at Dec. 31, 2021		64,900,000