Earnings per Share (Antidilutive Shares) (Details) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Anti-dilutive potential shares due to net loss	2	5

Antidilutive Securities Excluded from Computation of Earnings Per Share Due to Net Loss, Amount

No definition available.

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