Debt Notes and Debentures (Details) (USD $)							1 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Aug. 31, 2014 Corporate Debt Securities Three Point Four Zero Zero Percent Debentures Due September 1, 2024 [Member]	Aug. 31, 2014 Corporate Debt Securities Four Point Five Five Zero Percent Debentures Due September 1, 2044 [Member]	Mar. 31, 2014 Corporate Debt Securities Three Point Seven Five Zero Percent Debentures Due April 1, 2024 [Member]	Mar. 31, 2014 Corporate Debt Securities Four Point Nine Zero Zero Percent Debentures Due April 1, 2044 [Member]	Apr. 30, 2014 SEC Debt Shelf Registration	Sep. 30, 2014 SEC Debt Shelf Registration	Sep. 30, 2014 Junior Subordinated Debt
Debt Instrument [Line Items]
Additional Debt Securities Authorized For Issuance By The Board of Managers							$ 3,000,000,000
Debentures issued amount			700,000,000	800,000,000	500,000,000	1,000,000,000
Debentures interest rate			3.40%	4.55%	3.75%	4.90%
Remaining amount of debt securities that may be issued								1,750,000,000
Subordinated notes related to financial covenants									500,000,000
Debt, fair value	19,952,000,000	16,507,000,000
Debt, book value	$ 18,487,000,000	$ 16,066,000,000