Schedule II - Condensed Financial Information of Registrant - Condensed Balance Sheet of Registrant (Details) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
ASSETS
Cash and cash equivalents	$ 497.3	$ 661.2	$ 728.8	$ 677.0
Receivables, net	556.3	613.9
Property, plant and equipment, net (Note 11)	543.4	509.5
Assets	35,792.8	35,031.5
LIABILITIES AND EQUITY
Long-term debt	5,540.7	6,112.1
Deferred tax liabilities (Note 19)	546.0	574.5
Other liabilities	32.0	56.3
Total liabilities	33,975.6	33,443.4
Stockholders’ equity:
Common stock, $0.01 par; 500,000.0 thousand shares authorized; 200,789.1 thousand and 201,383.8 thousand shares issued and outstanding at September 30, 2016 and 2015, respectively.	2.0	2.0
Accumulated deficit	(1,031.9)	(833.1)
Accumulated other comprehensive income (loss)	220.9	(40.7)	243.6
Total permanent equity	1,817.2	1,588.1	2,257.0	1,133.5
Total liabilities and equity	35,792.8	35,031.5
HGI
ASSETS
Cash and cash equivalents	170.9	297.2	$ 420.0	$ 256.9
Receivables, net	0.1	0.8
Total current assets	171.0	298.0
Investments in subsidiaries and affiliates	1,870.1	2,040.8
Advances to consolidated subsidiaries	9.6	9.5
Deferred Tax Assets, Net, Current	351.2	2.0
Property, plant and equipment, net (Note 11)	1.1	1.3
Deferred charges and other assets	0.6	1.1
Assets	2,403.6	2,352.7
LIABILITIES AND EQUITY
Accounts payable	0.2	1.6
Accrued and other current liabilities	48.2	51.8
Total current liabilities	48.4	53.4
Long-term debt	1,711.2	1,705.1
Employee benefit obligations	5.2	4.7
Deferred tax liabilities (Note 19)	0.0	2.0
Other liabilities	0.7	0.8
Total liabilities	1,765.5	1,766.0
Stockholders’ equity:
Common stock, $0.01 par; 500,000.0 thousand shares authorized; 200,789.1 thousand and 201,383.8 thousand shares issued and outstanding at September 30, 2016 and 2015, respectively.	2.0	2.0
Additional paid-in capital	1,447.1	1,458.5
Accumulated deficit	(1,031.9)	(833.1)
Accumulated other comprehensive income (loss)	220.9	(40.7)
Total permanent equity	638.1	586.7
Total liabilities and equity	$ 2,403.6	$ 2,352.7

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).