Business and Basis of Presentation (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015 USD ($) Company	Dec. 31, 2014 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of holding companies having public debt outstanding | Company	2
Debt issuance cost	$ 5
Fair value of investments elected to calculate net asset per share	$ 45	$ 76