Earnings per Share (Antidilutive Shares) (Details) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]
Anti-dilutive potential shares	0	2	1	2
Anti-dilutive potential shares due to net loss	0	0	6	5

Antidilutive Securities Excluded from Computation of Earnings Per Share Due to Exercise Price Exceeding Market Price, Amount

No definition available.

Name:	wft_AntidilutiveSecuritiesExcludedfromComputationofEarningsPerShareDuetoExercisePriceExceedingMarketPriceAmount
Namespace Prefix:	wft_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration