Consolidating Financial Information - Schedule of Income Statement Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Revenues:
Net sales	$ 766.1	$ 756.4	$ 1,412.6	$ 1,358.7
Net investment income		1.0		1.0
Total revenues	766.1	757.4	1,412.6	1,359.7
Operating costs and expenses:
Cost of goods sold	494.8	445.6	898.6	807.7
Selling, acquisition, operating and general expenses	242.4	216.5	458.5	415.4
Total operating costs and expenses	737.2	662.1	1,357.1	1,223.1
Operating income	28.9	95.3	55.5	136.6
Interest expense	(67.6)	(77.7)	(143.1)	(156.4)
Other income (expense), net	0.2	(1.4)	1.2	(0.4)
(Loss) income from continuing operations before income taxes	(38.5)	16.2	(86.4)	(20.2)
Income tax (benefit) expense	(1.2)	24.0	(127.2)	29.6
Net (loss) income from continuing operations	(36.6)	(51.4)	542.3	209.4
Less: Net income attributable to noncontrolling interest	0.5	30.7	72.0	79.3
Net (loss) income attributable to controlling interest	(37.1)	(82.1)	470.3	130.1
Net (loss) income attributable to common and participating preferred stockholders	(37.1)	(82.1)	470.3	130.1
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0.7	(43.6)	501.5	259.2
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(37.3)	(7.8)	40.8	(49.8)
Corporate and Other and eliminations [Member]
Revenues:
Net sales			0.0	0.0
Net investment income				1.0
Total revenues				1.0
Operating costs and expenses:
Cost of goods sold			0.0	0.0
Selling, acquisition, operating and general expenses			21.6	30.7
Total operating costs and expenses			21.6	30.7
Operating income			(21.6)	(29.7)
Interest expense			(62.5)	(74.5)
Other income (expense), net			3.9	0.5
(Loss) income from continuing operations before income taxes			(80.2)	(103.7)
Income tax (benefit) expense			0.0	(1.5)
Net (loss) income from continuing operations			(80.2)	(102.2)
Less: Net income attributable to noncontrolling interest			0.0	(0.1)
Net (loss) income attributable to controlling interest			(80.2)	(102.1)
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest			0.0	0.0
Consumer Products Segment [Member]
Revenues:
Net sales			1,412.6	1,358.7
Total revenues	766.1	756.4	1,412.6	1,358.7
Operating costs and expenses:
Cost of goods sold			898.6	807.7
Selling, acquisition, operating and general expenses			436.9	384.7
Total operating costs and expenses			1,335.5	1,192.4
Operating income	43.1	104.8	77.1	166.3
Interest expense			(80.6)	(81.9)
Other income (expense), net			(2.7)	(0.9)
(Loss) income from continuing operations before income taxes			(6.2)	83.5
Income tax (benefit) expense			(127.2)	31.1
Net (loss) income from continuing operations			162.6	123.9
Less: Net income attributable to noncontrolling interest			66.6	51.9
Net (loss) income attributable to controlling interest			96.0	72.0
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest			41.6	71.5
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest			121.0	52.4
Corporate and Other [Member]
Revenues:
Total revenues		1.0		1.0
Operating costs and expenses:
Operating income	$ (14.2)	$ (9.5)
Discontinued Operations, Held-for-sale [Member]
Revenues:
Total revenues				0.0
Operating costs and expenses:
Operating income			0.0	0.0
Net (loss) income from continuing operations			459.9	187.7
Less: Net income attributable to noncontrolling interest			5.4	27.5
Net (loss) income attributable to controlling interest			454.5	160.2
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest			459.9	187.7
Consolidated Entities
Revenues:
Net sales			1,412.6	1,358.7
Net investment income				1.0
Total revenues				1,359.7
Operating costs and expenses:
Cost of goods sold			898.6	807.7
Selling, acquisition, operating and general expenses			458.5	415.4
Total operating costs and expenses			1,357.1	1,223.1
Operating income			55.5	136.6
Interest expense			(143.1)	(156.4)
Other income (expense), net			1.2	(0.4)
(Loss) income from continuing operations before income taxes			(86.4)	(20.2)
Income tax (benefit) expense			(127.2)	29.6
Net (loss) income from continuing operations			542.3	209.4
Less: Net income attributable to noncontrolling interest			72.0	79.3
Net (loss) income attributable to controlling interest			470.3	130.1
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest			501.5	259.2
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest			40.8	(49.8)
HGI | Discontinued Operations, Held-for-sale [Member]
Operating costs and expenses:
Net (loss) income attributable to controlling interest			$ 479.0	$ 201.7