Derivatives and Fair Value Measurements - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended					6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 Foreign Exchange Forward [Member]	Dec. 31, 2013 Foreign Exchange Forward [Member]	Jun. 30, 2014 Nickel Futures or Option Contracts [Member] T	Dec. 31, 2013 Nickel Futures or Option Contracts [Member] T	Jun. 30, 2014 Hot Roll Steel Coil Option [Member] T	Dec. 31, 2013 Hot Roll Steel Coil Option [Member] T	Jun. 30, 2014 Aluminum Price Swaps [Member] T	Dec. 31, 2013 Aluminum Price Swaps [Member] T	Jun. 30, 2014 Minimum [Member]	Jun. 30, 2014 Maximum [Member]
Derivatives, Fair Value [Line Items]
Notional amount of foreign currency exchange contracts				$ 0.8	$ 2.2
Commodity notional value						58	131	1,940	4,600	209	195
Contract term for exchange contracts, Maximum												3 months	12 months
Assets held for sale	3.7		4.7
Impairment charge of asset held for sale	0	0.9
Proceeds from sale of investments	$ 0