NOTES PAYABLE, LONG-TERM DEBT AND AVAILABLE CREDIT FACILITIES NOTES PAYABLE, LONG-TERM DEBT AND AVAILABLE CREDIT FACILITIES (Schedule of Committed and Available Credit Facilities) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Apr. 05, 2013
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 6,070
Line of Credit Facility, Remaining Borrowing Capacity	5,770
Five Year Competitive Advance and Revolving Credit Facility Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	5,000
Line of Credit Facility, Remaining Borrowing Capacity	5,000
$170M Revolving Credit Facility Due 10/2016 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	170
Line of Credit Facility, Remaining Borrowing Capacity	170
$100M Revolving Credit Facility Due 3/2014 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	100
Line of Credit Facility, Remaining Borrowing Capacity	100
$300M Revolving Credit Facility Due 10/2016 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	300
Line of Credit Facility, Remaining Borrowing Capacity	300
Term Loan Facility [Domain]
Line of Credit Facility [Line Items]
Long-term Line of Credit, Noncurrent		300
Line of Credit Facility, Maximum Borrowing Capacity	300
Line of Credit Facility, Remaining Borrowing Capacity	0
$200M Revolving Credit Facility due 4/2016 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	200
$200 Million Revolving Credit Facility Due 4/2016 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 200