Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2017
Income Taxes [Line Items]
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	$ 10.4
Document Period End Date			Mar. 31, 2018
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%		35.00%
Income tax (benefit) expense	$ (1.2)	$ 24.0	$ (127.2)	$ 29.6
Deferred income taxes			$ (151.6)	$ (1.5)
Effective Income Tax Rate Reconciliation, Percent	3.10%	148.10%	147.20%	(146.50%)
U S Federal [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards	$ 387.9		$ 387.9
HGI
Income Taxes [Line Items]
Deferred Tax Assets, Valuation Allowance	441.2		441.2		$ 703.2
HGI | U S Federal [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards					1,524.3
Capital Loss Carryforwards					315.9
FGL [Member]
Income Taxes [Line Items]
Deferred Tax Assets, Valuation Allowance	34.4		34.4		58.1
FGL [Member] | U S Federal [Member]
Income Taxes [Line Items]
Operating Loss Carryforwards					151.1
FGL [Member] | Domestic Tax Authority [Member]
Income Taxes [Line Items]
Capital Loss Carryforwards					$ 15.0
H G I [Member]
Income Taxes [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount			287.2
Spectrum Brands [Member]
Income Taxes [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	4.9
Increase in Unrecognized Tax Benefits is Reasonably Possible	41.9		41.9
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			613.1
Undistributed Earnings of Foreign Subsidiaries	1.0		1.0
Spectrum Brands [Member] | Other Current Liabilities [Member]
Income Taxes [Line Items]
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries	6.3		6.3
Spectrum Brands [Member] | Other Liabilities [Member]
Income Taxes [Line Items]
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries	71.7		71.7
Spectrum Brands [Member] | Deferred Tax Assets, Valuation Allowance, Foreign Income Taxes [Member]
Income Taxes [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount			78.0
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			78.0
Spectrum Brands [Member] | Deferred Tax Assets, Valuation Allowance, US State and Local Income Taxes [Member]
Income Taxes [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 5.5		35.9
Income tax (benefit) expense			$ 206.7