Short And Long-Term Debt Unsecured Notes (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	6 Months Ended		0 Months Ended		1 Months Ended		1 Months Ended
	Apr. 30, 2013	Jun. 30, 2013	Jun. 30, 2012	May 29, 2013 Senior Notes [Member] 11.50% Senior Notes	Apr. 26, 2013 Senior Notes [Member] 11.50% Senior Notes	Apr. 30, 2013 Senior Notes [Member] 12.00% Senior Notes	Apr. 16, 2013 Senior Notes [Member] 12.00% Senior Notes	Apr. 30, 2013 Senior Notes [Member] 3.375% Senior Notes	Jun. 30, 2013 Senior Notes [Member] 3.375% Senior Notes	Apr. 26, 2013 Senior Notes [Member] 3.375% Senior Notes
Debt Instrument [Line Items]
Early Repayment of Subordinated Debt	$ 201
Remaining Proceeds from IPO used to Redeem Debt	218
Interest Rate					11.50%		12.00%		3.375%	3.375%
Proceeds from issuance of Senior Notes		500	0					494
Debt Redemption Premium				106.00%		106.00%
Debt instrument, face amount					$ 492		$ 130		$ 500	$ 500