Preferred and Common Stock - Schedule of Share Activity (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury stock, beginning balance	87,150,169	106,895,705	110,694,604
Treasury stock, ending balance	81,051,103	87,150,169	106,895,705
Common Stock Outstanding, beginning balance	1,216,663,661	1,071,011,162	1,067,211,953
Common Stock Outstanding, ending balance	1,310,160,141	1,216,663,661	1,071,011,162
Outstanding Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion of convertible notes		89,383,953	310
Acquisition of RTI	87,397,414
Private placement		36,523,010
Issued for stock-based compensation plans	6,099,066	19,745,536	3,798,899
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issued for stock-based compensation plans	(6,099,066)	(19,745,536)	(3,798,899)