Subsequent Events - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jan. 02, 2014 The Liquid Fence Company [Member] Subsequent Event [Member]	Jan. 15, 2014 Seven Point Seven Five Percent Senior Unsecured Notes [Member] HGI [Member] Subsequent Event [Member]	Dec. 31, 2013 7.875% Senior Secured Notes, due July 15, 2019 [Member] HGI [Member]	Sep. 30, 2013 7.875% Senior Secured Notes, due July 15, 2019 [Member] HGI [Member]
Subsequent Event [Line Items]
Long-term Debt	$ 5,175.4	$ 4,909.7		$ 200.0	$ 925.0	$ 925.0
Long-term debt, interest rate				7.75%	7.90%	0.00%
Debt Instrument Discount Rate				100.00%
Business Combination Purchase Consideration Transferred			$ 34.8