Business Segments - Schedule of Comparison of Approximate Sales Mix in Principal Product Categories (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Entity Wide Portfolio Carrying Amount Major Customer [Line Items]
Total Revenues	$ 669	$ 697	$ 651	$ 631	$ 538	$ 520	$ 501	$ 548	$ 2,648	$ 2,107	$ 3,010
Drilling and Production [Member]
Entity Wide Portfolio Carrying Amount Major Customer [Line Items]
Total Revenues									625	496	632
Pipe [Member]
Entity Wide Portfolio Carrying Amount Major Customer [Line Items]
Total Revenues									418	287	509
Valves [Member]
Entity Wide Portfolio Carrying Amount Major Customer [Line Items]
Total Revenues									541	374	538
Fittings and Flanges [Member]
Entity Wide Portfolio Carrying Amount Major Customer [Line Items]
Total Revenues									419	350	448
Mill Tool, MRO, Safety and Other [Member]
Entity Wide Portfolio Carrying Amount Major Customer [Line Items]
Total Revenues									$ 645	$ 600	$ 883