CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY/(DEFICIT) - USD ($) $ in Millions	Total	Common Stock	Preferred Stock	Preferred Stock	Preferred Stock Preferred Stock	Common Stock	Common Stock Common Stock	Additional Paid-in Capital	Additional Paid-in Capital Common Stock	Additional Paid-in Capital Preferred Stock	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive (Loss)/Income
Dividends per common share (in dollars per share)	$ 0.29
Beginning Balance at Sep. 30, 2017	$ 85.1					$ 0.6		$ 196.7			$ 198.7	$ (72.1)	$ (238.8)
Beginning Balance (in shares) at Sep. 30, 2017						60,709,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)/earnings	60.4										60.4
Share based payments	6.7							6.7
Activity under stock plans	(1.8)							(4.8)			(0.8)	3.8
Activity under stock plans (in shares)						91,000
Dividends to shareholders ($0.30 per share)	(18.7)										(18.7)
Other comprehensive loss	11.1												11.1
Common stock purchased	(50.0)											(50.0)
Common stock purchased (in shares)						(1,126,000)
Ending Balance at Dec. 31, 2017	33.6					$ 0.6		198.6			180.4	(118.3)	(227.7)
Ending Balance (in shares) at Dec. 31, 2017						59,674,000
Beginning Balance at Sep. 30, 2017	85.1					$ 0.6		196.7			198.7	(72.1)	(238.8)
Beginning Balance (in shares) at Sep. 30, 2017						60,709,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends to common shareholders ($0.30 per share)	0.0
Net earnings from continuing operations	92.0
Loss from discontinued operations, net of tax	0.0
Common stock purchased	$ (50.0)
Common stock purchased (in shares)	(1,126,379)
Ending Balance at Jun. 30, 2018	$ 47.8					$ 0.6		224.4			196.4	(117.7)	(255.9)
Ending Balance (in shares) at Jun. 30, 2018						59,686,000
Dividends per common share (in dollars per share)	$ 0.29
Beginning Balance at Dec. 31, 2017	$ 33.6					$ 0.6		198.6			180.4	(118.3)	(227.7)
Beginning Balance (in shares) at Dec. 31, 2017						59,674,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)/earnings	7.8										7.8
Share based payments	7.3							7.3
Activity under stock plans	0.1							(0.5)				0.6
Activity under stock plans (in shares)						12,000
Dividends to shareholders ($0.30 per share)	(17.8)										(17.8)
Other comprehensive loss	13.7												13.7
Ending Balance at Mar. 31, 2018	$ 44.7					$ 0.6		205.4			190.5	(117.7)	(234.1)
Ending Balance (in shares) at Mar. 31, 2018						59,686,000
Dividends per common share (in dollars per share)	$ 0.29
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)/earnings	$ 23.8										23.8
Share based payments	7.0							7.0
Activity under stock plans	12.0							12.0
Dividends to shareholders ($0.30 per share)	(17.9)										(17.9)
Other comprehensive loss	(21.8)												(21.8)
Net earnings from continuing operations	23.8
Loss from discontinued operations, net of tax	0.0
Ending Balance at Jun. 30, 2018	$ 47.8					$ 0.6		224.4			196.4	(117.7)	(255.9)
Ending Balance (in shares) at Jun. 30, 2018						59,686,000
Dividends per common share (in dollars per share)	$ 0.30
Beginning Balance at Sep. 30, 2018	$ 24.5					$ 0.6		217.8			177.3	(129.4)	(241.8)
Beginning Balance (in shares) at Sep. 30, 2018						59,608,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss)/earnings	70.8										70.8
Share based payments	6.5							6.5
Activity under stock plans	(7.1)							(16.1)			(3.6)	12.6
Activity under stock plans (in shares)						290,000
Dividends to shareholders ($0.30 per share)	(18.4)										(18.4)
Other comprehensive loss	(5.9)												(5.9)
Ending Balance at Dec. 31, 2018	$ 70.4					$ 0.6		208.2			226.1	(116.8)	(247.7)
Ending Balance (in shares) at Dec. 31, 2018						59,898,000
Preferred stock dividend declared (in dollars per share)	$ 7,700,000
Beginning Balance at Sep. 30, 2018	$ 24.5					$ 0.6		217.8			177.3	(129.4)	(241.8)
Beginning Balance (in shares) at Sep. 30, 2018						59,608,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends to common shareholders ($0.30 per share)	(4.0)
Net earnings from continuing operations	17.7
Loss from discontinued operations, net of tax	(12.8)
Common stock purchased	$ (45.0)
Common stock purchased (in shares)	(1,036,000)
Ending Balance at Jun. 30, 2019	$ 570.7					$ 0.7		867.2			109.5	(161.4)	(245.3)
Ending Balance (in shares) at Jun. 30, 2019						68,840,000
Dividends per common share (in dollars per share)	$ 0.30
Preferred stock dividend declared (in dollars per share)	$ 1.83
Beginning Balance at Dec. 31, 2018	$ 70.4					$ 0.6		208.2			226.1	(116.8)	(247.7)
Beginning Balance (in shares) at Dec. 31, 2018						59,898,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share based payments	7.6							7.6
Activity under stock plans	0.0							(0.5)				0.5
Activity under stock plans (in shares)						11,000
Dividends to shareholders ($0.30 per share)	(21.6)										(21.6)
Dividends to common shareholders ($0.30 per share)	(3.3)										(3.3)
Other comprehensive loss	20.2												20.2
Net earnings from continuing operations	(62.3)										(62.3)
Loss from discontinued operations, net of tax	(11.0)										(11.0)
Issuance of stock		$ 445.8	$ 199.5				$ 0.1		$ 445.7	$ 199.5
Issuance of stock (in shares)					2,156,000		9,966,000
Ending Balance at Mar. 31, 2019	$ 645.3					$ 0.7		860.5			127.9	(116.3)	(227.5)
Ending Balance (in shares) at Mar. 31, 2019						69,875,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred Stock, Shares Outstanding				2,156,000
Dividends per common share (in dollars per share)	$ 0.30
Preferred stock dividend declared (in dollars per share)	$ 1.875
Net (loss)/earnings	$ 9.2										9.2
Share based payments	6.7							6.7
Activity under stock plans	(0.1)											(0.1)
Activity under stock plans (in shares)						1,000
Dividends to shareholders ($0.30 per share)	(21.4)										(21.4)
Dividends to common shareholders ($0.30 per share)	(4.4)										(4.4)
Other comprehensive loss	(17.8)												(17.8)
Net earnings from continuing operations	9.2
Loss from discontinued operations, net of tax	(1.8)										(1.8)
Common stock purchased	(45.0)											(45.0)
Common stock purchased (in shares)						(1,036,000)
Ending Balance at Jun. 30, 2019	$ 570.7					$ 0.7		$ 867.2			$ 109.5	$ (161.4)	$ (245.3)
Ending Balance (in shares) at Jun. 30, 2019						68,840,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred Stock, Shares Outstanding				2,156,000