XML 24 R52.htm IDEA: XBRL DOCUMENT

Debt and Interest Expense - Debt Activity Table (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Debt Disclosure [Abstract]
Carrying value, beginning balance	$ 13,269
Debt Instrument [Line Items]
Other, net	9
Carrying value, ending balance	13,663
Western Gas Partners Limited Partnership [Member] \| Borrowings [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowings	$ 385

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References+ Details

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References+ Details