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Earnings Per Share - Additional Information (Detail) - $ / shares	1 Months Ended		3 Months Ended			9 Months Ended
	Jul. 31, 2015	Mar. 31, 2015	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2015	Sep. 30, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock outstanding			1,000,000	8,000,000		4,000,000	6,000,000
Number of weighted average outstanding diluted shares			1,294,000,000	1,205,000,000		1,257,000,000	1,170,000,000
Basic average number of share			58,000,000			20,000,000
Weighted average number of shares outstanding			1,281,000,000	1,177,000,000		1,241,000,000	1,150,000,000
RTI [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of common stock shares issued in a part of acquisition	87,000,000	87,397,414
Weighted average number of shares outstanding			87,000,000			87,000,000
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares, option exercised					89,000,000
Common stock outstanding				89,000,000			89,000,000
Number of weighted average outstanding shares included in both basic and diluted shares							67,000,000
Common stock outstanding							89,000,000
Number of weighted average outstanding diluted shares							22,000,000
Equity Unit Purchase Agreements [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities						26,000,000	3,000,000
Stock options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average exercise price of options						$ 12.76	$ 16.24
Mandatory Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities			77,000,000			77,000,000
Convertible Notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities			25,000,000			8,000,000

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