Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2015

The net carrying and estimated fair values of our financial instruments by class at June 30, 2015 and December 31, 2014 were as follows:



	June 30, 2015				December 31, 2014
	Net Carrying Amount		Fair Value		Net Carrying Amount		Fair Value
	(Millions)
Long-term debt (including current maturities)	$	1,104	$	1,146	$	1,057	$	1,106
Instruments with off-balance sheet risk:
Foreign exchange forward contracts:
Asset derivative contracts	—		—		—		—

Summarization for Foreign Currency Forward Purchase and Sale Contracts

The following table summarizes by major currency the notional amounts for foreign currency forward purchase and sale contracts as of June 30, 2015 (all of which mature in 2015):



		Notional Amount in Foreign Currency
		(Millions)
Australian dollars	—Purchase	1
	—Sell	(1	)
British pounds	—Purchase	10
	—Sell	(25	)
Canadian dollars	—Sell	(6	)
European euro	—Purchase	7
	—Sell	(10	)
South African rand	—Purchase	112
Japanese yen	—Purchase	228
	—Sell	(604	)
U.S. dollars	—Purchase	60
	—Sell	(35	)
Other	—Purchase	1