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) $ in Millions		Jun. 30, 2015 USD ($)
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 6,300
Line of Credit Facility, Remaining Borrowing Capacity		6,000
Five Year Competitive Advance and Revolving Credit Facility Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	[1]	5,000
Line of Credit Facility, Remaining Borrowing Capacity	[1]	5,000
$100M Revolving Credit Facility Due 3/2016 [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]
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, Maximum Borrowing Capacity		200
Line of Credit Facility, Remaining Borrowing Capacity		200
$200 Million Revolving Credit Facility Due 10/2016 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		200
Line of Credit Facility, Remaining Borrowing Capacity		200
$100 Million Revolving Credit Facility Due 10/2016 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		100
Line of Credit Facility, Remaining Borrowing Capacity		100
$100 Million 1/2014 Revolving Credit Facility Due 10/2016 [Domain]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		100
Line of Credit Facility, Remaining Borrowing Capacity		$ 100

[1] The prior credit facility was terminated and replaced with a new credit facility, with substantially similar terms and conditions, on March 24, 2015.