Commitments and Contingencies - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2015 USD ($)
Loss Contingencies [Line Items]
Annual workers' compensation costs (up to $0.5 million)	$ 500,000.0
Global Brass and Copper Employees Excluding Chase [Member]
Loss Contingencies [Line Items]
Comprehensive Medical Plans, Stop loss policy deductible per participant	300,000.0
Chase Brass [Member]
Loss Contingencies [Line Items]
Comprehensive Medical Plans, Stop loss policy deductible per participant	100,000.0
Medical plan stop loss maximum	$ 2,000,000.0