Consolidated Statement Of Stockholders' Equity - USD ($) $ in Millions	Total	Common stock	Additional paid-in capital	Accumulated deficit	Accumulated other comprehensive income (loss)	Noncontrolling Interest [Member]	Stock-based Compensation Related [Member]	Stock-based Compensation Related [Member] Common stock	Stock-based Compensation Related [Member] Additional paid-in capital	Stock-based Compensation Related [Member] Accumulated deficit	Stock-based Compensation Related [Member] Accumulated other comprehensive income (loss)	Stock-based Compensation Related [Member] Noncontrolling Interest [Member]	Stock Repurchase Program [Member]	Stock Repurchase Program [Member] Common stock	Stock Repurchase Program [Member] Additional paid-in capital	Stock Repurchase Program [Member] Accumulated deficit	Stock Repurchase Program [Member] Accumulated other comprehensive income (loss)	Stock Repurchase Program [Member] Noncontrolling Interest [Member]
Balance at Sep. 30, 2012	$ 231.2	$ 1.6	$ 1,587.3	$ (1,270.0)	$ (87.7)	$ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	40.8
Net Income (Loss) Attributable to Noncontrolling Interest						0.0
Net Income (Loss) Attributable to Parent	40.8	0.0	0.0	40.8	0.0
Dividends declared	(11.0)	0.0	(11.0)	0.0	0.0	0.0
Stock-based compensation	6.5	0.0	6.5	0.0	0.0	0.0
Shares retained for employee taxes							$ (1.5)	$ 0.0	$ (1.5)	$ 0.0	$ 0.0	$ 0.0
Stock issued under stock compensation plans	3.1	0.0	3.1	0.0	0.0	0.0
Other Comprehensive Income (Loss), Net of Tax	59.1	0.0	0.0	0.0	59.1	0.0
Balance at Sep. 30, 2013	328.2	1.6	1,584.4	(1,229.2)	(28.6)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	55.4
Net Income (Loss) Attributable to Noncontrolling Interest						(0.1)
Net Income (Loss) Attributable to Parent	55.5	0.0	0.0	55.5	0.0
Dividends declared	(11.2)	0.0	(11.2)	0.0	0.0	0.0
Stock-based compensation	8.5	0.0	8.5	0.0	0.0	0.0
Shares retained for employee taxes							(3.1)	0.0	$ (3.1)	0.0	0.0	0.0
Stock issued under stock compensation plans	4.2	0.0	4.2	0.0	0.0	0.0
Payments to Acquire Interest in Joint Venture	1.7	0.0	0.0	0.0	0.0	1.7
Other Comprehensive Income (Loss), Net of Tax	(32.1)	0.0	0.0	0.0	(32.1)	0.0
Balance at Sep. 30, 2014	351.6	1.6	1,582.8	(1,173.7)	(60.7)	1.6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	30.8
Net Income (Loss) Attributable to Noncontrolling Interest						(0.1)
Net Income (Loss) Attributable to Parent	30.9	0.0	0.0		0.0
Dividends declared	(12.0)	0.0	(12.0)	0.0	0.0	0.0
Stock-based compensation	4.9	0.0	4.9	0.0	0.0	0.0
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net	3.2	0.0	3.2	0.0	0.0	0.0
Shares retained for employee taxes							$ (2.4)	$ 0.0		$ 0.0	$ 0.0	$ 0.0	$ (5.0)	$ 0.0	$ (5.0)	$ 0.0	$ 0.0	$ 0.0
Stock issued under stock compensation plans	3.3	0.0	3.3	0.0	0.0	0.0
Payments to Acquire Interest in Joint Venture	1.7
Other Comprehensive Income (Loss), Net of Tax	(6.6)	0.0	0.0	0.0	(6.6)	0.0
Balance at Sep. 30, 2015	$ 367.8	$ 1.6	$ 1,574.8	$ (1,142.8)	$ (67.3)	$ 1.5