Debt and Banking Arrangements Debt and Banking Arrangements (Tables)

3 Months Ended

Mar. 31, 2015

Debt Disclosure [Abstract]

Schedule of Line of Credit Facilities [Table Text Block]

Credit Facilities

On February 2, 2015, we entered into a Credit Agreement with aggregate commitments remaining at $1.5 billion, and the credit facilities for Pre-merger WPZ and ACMP were terminated in connection with the Merger. WPZ also entered into a $3.5 billion credit facility.

	March 31, 2015
	Stated Capacity		Outstanding
	(Millions)
WMB
Loans	$	1,500	$	375
Swingline loans sublimit	50		—
Letters of credit sublimit	675		—
Letters of credit under certain bilateral bank agreements			15
WPZ
Loans	3,500		—
Swingline loans sublimit	150		—
Letters of credit sublimit	1,125		2
Letters of credit under certain bilateral bank agreements			3