Significant Accounting Policies and Practices and Recent Accounting Pronouncements - Benefit Expense and Other Changes in Policy Reserves (Details) - FIA embedded derivatives, included in contractholder funds	12 Months Ended
	Sep. 30, 2016
Minimum [Member]
Schedule of Benefits and Other Changes in Policy Reserves [Line Items]
Interest Crediting Rates for Funds at Subsidiaries	0.00%
Maximum
Schedule of Benefits and Other Changes in Policy Reserves [Line Items]
Interest Crediting Rates for Funds at Subsidiaries	6.00%