Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Entity	Dec. 31, 2011	Dec. 31, 2010
Significant Accounting Policies [Line Items]
Revenues derived from percentage of completion accounting, percentage	15.00%	15.00%	14.00%
Net costs and estimated earnings in excess of billings on uncompleted contracts	$ 95.9	$ 72.2
Excess over average costs on long term contracts	134.4	87.1
Allowance for doubtful accounts	12.1	8.2
Number of reportable units	6
Percentage of discounted closing price for Employee Stock Purchase Plan	85.00%
Employee Stock Purchase Plan, rights granted	0.9	0.7	0.5
Purchase of treasury stock, share	60,266	161,297	197,343
Purchase of treasury stock	$ 2.6	$ 6.0	$ 6.7
Percentage of revenues	No other individual customers accounted for more than 10% of the Company's consolidated net sales	No single customer accounted for more than 10% of the Company's consolidated net sales	No single customer accounted for more than 10% of the Company's consolidated net sales
Boeing
Significant Accounting Policies [Line Items]
Percentage of net sales	11.10%
Minimum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	1 year
Patent and other intangible assets, amortization period	2 years
Maximum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life	50 years
Patent and other intangible assets, amortization period	34 years