Acquisitions and Divestitures - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended	0 Months Ended
	Jun. 25, 2014	Jun. 25, 2014 Firth Rixson [Member]	Jun. 25, 2014 Firth Rixson [Member]
Business Acquisition [Line Items]
Business acquisition purchase price		$ 2,850
Cash paid for business acquisition		2,350
Value of common stock issued		500
Business acquisition potential earn-out			150
Common stock issued as part of acquisition	36,523,010	36,523,010
Business acquisition common stock issued, price per share	$ 13.69		$ 13.69
Business acquisition, unsecured bridge term loan			$ 2,500