Debt and Banking Arrangements (Tables)

6 Months Ended

Jun. 30, 2011

Debt and Banking Arrangements [Abstract]

Letters of credit issued and loans outstanding under line of credit facilities

		Letters
	Expiration	of Credit		Loans
		(Millions)
$900 million unsecured credit facility (1)	June 3, 2016	$	—	$	—
$2 billion WPZ unsecured credit facility (2) (3)	June 3, 2016		—		350
Bilateral bank agreements for letters of credit			74
		$	74	$	350

(1)	$700 million letter of credit capacity.
(2)	$1.3 billion letter of credit capacity.
(3)	Subsequent to June 30, 2011, WPZ repaid a net $100 million of this loan balance.