Acquisitions - Composite Engineering, Inc. (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended			0 Months Ended		3 Months Ended	9 Months Ended		0 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013 Revolving credit facility	Jul. 02, 2012 Composite Engineering, Inc.	May 14, 2012 Composite Engineering, Inc.	Sep. 29, 2013 Composite Engineering, Inc.	Sep. 29, 2013 Composite Engineering, Inc.	Jul. 02, 2012 Composite Engineering, Inc. Revolving credit facility	Jul. 02, 2012 Composite Engineering, Inc. Restricted Stock Units (RSUs) Management
Business Acquisition [Line Items]
Consideration transferred				$ 164.0
Aggregate amount of cash paid				135.0
Number of shares given as part of purchase price				4.0
Purchase price per share				$ 5.94	$ 5.00
Common stock exchanged as consideration, value				23.8
Amount of cash paid placed in escrow				10.7
Working capital adjustment paid to the Company				1.0
Consideration transferred, retirement of acquiree's debt				2.5
Consideration transferred, settlement of pre-existing accounts receivable				3.0
Additional tax liability incurred				1.6
Estimate of tax deductible goodwill and intangible assets				140.6
Tax deductible goodwill, deduction realization period				15 years
Number of shares issued as part of long-term employment agreements									2.0
Fair value of shares issued as part of long-term employment agreements									11.9
Share-based compensation, period for recognition									4 years
Common stock issued for acquisitions	0	4.0		20.0	20.0
Gross proceeds from issuance of common stock					100.0
Proceeds from the issuance of common stock	0	97.0			97.0
Outstanding borrowings			0					40.0
Acquired accounts receivable, gross				9.3
Revenues of CEI included in the Company's financial statements						23.8	76.8
Operating income (loss) of CEI included in the Company's financial statements						$ 7.4	$ 14.2