Shareholders' Equity (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended	3 Months Ended				4 Months Ended
	Apr. 13, 2014	Apr. 14, 2013	Apr. 13, 2014	Apr. 14, 2013	Sep. 29, 2013	Apr. 13, 2014 Dividend Declared [Member]	Sep. 29, 2013 Dividend Declared [Member]	Jul. 07, 2013 Dividend Declared [Member]	Apr. 14, 2013 Dividend Declared [Member]	Jan. 19, 2014 Dividend Declared [Member]	Jan. 20, 2013 Dividend Declared [Member]	Jan. 20, 2013 Special Dividend [Member]
Dividends Per Common Share [Abstract]
Dividends Payable, Date Declared						Feb. 24, 2014	Sep. 10, 2013	Jun. 12, 2013	Mar. 15, 2013	Nov. 01, 2013	Nov. 07, 2012	Nov. 29, 2012
Dividends declared per common share (in dollars per share)	$ 0.12	$ 0.10	$ 0.24	$ 1.20	$ 1.40	$ 0.12	$ 0.10	$ 0.10	$ 0.10	$ 0.12	$ 0.10	$ 1.00
Dividends Payable, Date of Record						Apr. 11, 2014	Sep. 27, 2013	Jul. 05, 2013	Apr. 12, 2013	Jan. 17, 2014	Jan. 18, 2013	Dec. 10, 2012
Dividends Payable, Date to be Paid						Apr. 22, 2014	Oct. 08, 2013	Jul. 16, 2013	Apr. 23, 2013	Jan. 28, 2014	Jan. 29, 2013	Dec. 21, 2012
Dividends, Common Stock, Cash			$ 89		$ 519	$ 45	$ 37	$ 37	$ 37	$ 45	$ 37	$ 371