Acquisitions and Divestitures - Additional Information (Detail) $ / shares in Units, € in Millions, $ in Millions		1 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended
	Nov. 30, 2014 USD ($)	Mar. 31, 2015 EUR (€) Employees	Mar. 31, 2015 USD ($) Employees $ / shares shares	Mar. 31, 2015 USD ($) $ / shares Series shares	Jun. 30, 2015 USD ($)	Dec. 31, 2014 USD ($) Employees	Mar. 06, 2015 $ / shares
Business Acquisition [Line Items]
Goodwill					$ 5,232	$ 5,247
Russia [Member]
Business Acquisition [Line Items]
Net cash received					30
Loss from divestitures before income tax					159
Net loss, after tax and noncontrolling interest					149
Stupino Titanium Company [Member]
Business Acquisition [Line Items]
Number of employees | Employees		1,870	1,870
Generated sale,net			$ 130
Tital [Member]
Business Acquisition [Line Items]
Goodwill			$ 123	$ 123
Number of employees | Employees		650	650
Cash paid for business acquisition		€ 188	$ 204
RTI [Member]
Business Acquisition [Line Items]
Number of employees | Employees						2,600
Common stock estimated value			$ 1,100	$ 1,100
Business acquisition common stock issued, price per share | $ / shares			$ 12.92	$ 12.92			$ 14.48
Number of shares to be issued upon conversion | $ / shares			$ 2.8315	$ 2.8315
Acquisition price per share | $ / shares							$ 41
Common stock outstanding | shares			30,794,405	30,794,405
Assumed debt			$ 500	$ 500
Business acquisition cash assumed			300	300
Generated sale,net						$ 794
RTI [Member] | Senior Notes [Member] | Convertible Debt [Member]
Business Acquisition [Line Items]
Assumed debt			$ 500	$ 500
Number of additional series | Series				2
Conversion of convertible senior notes to common stock | shares				(13,070,774)
Firth Rixson [Member]
Business Acquisition [Line Items]
Business acquisition purchase price	$ 2,995
Contingent consideration	130
Total assets	3,470
Goodwill	1,898
Intangible assets	398				794
Total liabilities	$ 475
Properties, plants and equipment					165
Decrease in goodwill					396
Firth Rixson [Member] | Goodwill [Member]
Business Acquisition [Line Items]
Decrease in goodwill					$ (116)