Divestitures Divestitures - Schedule of intercompany assets and liabilities of disposal group (Details) - USD ($) $ in Millions	Dec. 31, 2016	Sep. 30, 2016
Related Party Transaction [Line Items]
Funds Withheld Receivable	$ 1,609.0	$ 1,650.4
Other assets	157.2	172.6
Disposal Group, Including Discontinued Operation, Assets, Current	26,801.6	26,738.7
Total assets	35,662.7	35,792.8
Insurance reserves	1,721.9	1,751.3
Debt	5,459.0	5,430.9	[1],[2]
Accounts payable and other current liabilities	900.4	989.8
Other liabilities	26.7	32.0
Disposal Group, Including Discontinued Operation, Liabilities, Current	25,200.5	25,100.2
Total liabilities	33,993.3	33,975.6
FGL [Member] | Majority-Owned Subsidiary, Unconsolidated [Member]
Related Party Transaction [Line Items]
Funds Withheld Receivable	939.5	978.8
Other assets	15.0	15.1
Disposal Group, Including Discontinued Operation, Assets, Current	1,349.0	1,375.5
Total assets	2,303.5	2,369.4
Insurance reserves	1,087.5	1,119.5
Debt	58.8	63.0
Disposal Group, Including Discontinued Operation, Liabilities, Current	1,157.2	1,186.9
Total liabilities	$ 2,303.5	$ 2,369.4

[1] The carrying value of cash and cash equivalents, trade receivables, accounts payable and accrued investment income approximate fair value due to their short duration and, accordingly, they are not presented in the tables above.

[2] The fair value of debt set forth above is generally based on quoted or observed market prices.