Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2011

Financial Instruments [Abstract]

Carrying and estimated fair value

	September 30, 2011				December 31, 2010
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(Millions)
Long-term debt (including current maturities)	$	1,236	$	1,245	$	1,162	$	1,201
Instruments with off-balance sheet risk:
Foreign exchange forward contracts:
Asset derivative contracts		—		—		2		2
Liability derivative contracts		2		2		—		—

Foreign exchange forward contracts fair value on gross basis

	Fair Value of Derivative Instruments
	September 30, 2011						December 31, 2010
	Asset		Liability				Asset		Liability
	Derivatives		Derivatives		Total		Derivatives		Derivatives		Total
	(Millions)
Foreign exchange forward contracts	$	—	$	2	$	2	$	2	$	—	$	2

Fair value of financial assets and liabilities on recurring basis

September 30, 2011

December 31, 2010

Level 1

Level 2

Level 3

Level 1

Level 2

Level 3

(Millions)

Financial Assets:

Foreign exchange contracts

n/a

$

—

n/a

n/a

$

2

n/a

Financial Liabilities:

Foreign exchange contracts

n/a

$

2

n/a

n/a

$

—

n/a

Summarization for foreign currency forward purchase and sale contracts

		Notional Amount
		in Foreign Currency
		(Millions)
Australian dollars	—Purchase		2
British pounds	—Purchase		4
European euro	—Sell		(9	)
Japanese Yen	—Purchase		442
South African rand	—Purchase		162
U.S. dollars	—Purchase		1
	—Sell		(23	)
Other	—Sell		(1	)