Condensed Consolidating Financial Statements - Balance Sheet (Details) (USD $) In Millions, unless otherwise specified	Jun. 24, 2012	Dec. 25, 2011	Jun. 26, 2011	Dec. 26, 2010	Jun. 24, 2012 Parent Company	Dec. 25, 2011 Parent Company	Jun. 24, 2012 Guarantors on a Combined Basis	Dec. 25, 2011 Guarantors on a Combined Basis	Jun. 24, 2012 Non-Guarantors on a Combined Basis	Dec. 25, 2011 Non-Guarantors on a Combined Basis	Jun. 24, 2012 Eliminations	Dec. 25, 2011 Eliminations	Sep. 30, 2012 Senior notes Senior Notes due June 2017	Jun. 24, 2012 Senior notes Senior Notes due June 2017	Jul. 27, 2011 Senior notes Senior Notes due June 2017	Mar. 25, 2011 Senior notes Senior Notes due June 2017	May 19, 2010 Senior notes Senior Notes due June 2017
Condensed Financial Statements, Captions [Line Items]
Principal	$ 631.2	$ 631.8											$ 625.0	$ 625.0	$ 115.0	$ 285.0	$ 225.0
Current assets:
Cash and cash equivalents	145.7	69.6	100.4	10.8	126.7	52.6	(0.3)	2.8	19.3	14.2	0	0
Restricted cash	0.8	1.1			0.5		0.3		0		0
Accounts receivable, net	256.8	245.3			0	0	235.7	225.4	21.1	19.9	0	0
Amounts due from affiliated companies	0	0			426.6	446.2	0	0	0	0	(426.6)	(446.2)
Inventoried costs	86.4	76.6			0	0	70.7	64.2	15.7	12.4	0	0
Prepaid expenses and other current assets (including restricted cash)		29.5				6.7		18.4		4.4		0
Prepaid expenses and other current assets	31.4				8.2		18.3		4.9		0
Total current assets	521.1	421.0			562.0	505.5	324.7	310.8	61.0	50.9	(426.6)	(446.2)
Property, plant and equipment, net	72.4	72.5			1.1	1.2	61.7	62.2	9.6	9.1	0	0
Goodwill	575.4	571.6			0	0	554.0	550.2	21.4	21.4	0	0
Intangible assets, net	107.2	124.6			0	0	103.7	119.8	3.5	4.8	0	0
Investment in subsidiaries	0	0			476.7	460.1	23.5	20.5	0	0	(500.2)	(480.6)
Amounts due from affiliated companies	0	0			0	0	26.0	26.0	0	0	(26.0)	(26.0)
Other assets	23.0	26.3			20.0	21.7	2.5	4.0	0.5	0.6	0	0
Total assets	1,299.1	1,216.0			1,059.8	988.5	1,096.1	1,093.5	96.0	86.8	(952.8)	(952.8)
Current liabilities:
Accounts payable	61.9	48.8			9.6	8.5	47.3	37.5	5.0	2.8	0	0
Accrued expenses	52.9	50.7				2.3		45.1		3.3		0
Accrued expenses (including interest payable)	58.0				1.7		53.6		2.7		0
Accrued compensation	33.8	39.8			2.4	3.7	28.6	33.3	2.8	2.8	0	0
Accrued interest payable	5.1	5.1				5.1		0		0		0
Billings in excess of costs and earnings on uncompleted contracts	37.1	36.2			0	0	32.0	34.3	5.1	1.9	0	0
Amounts due to affiliated companies	0	0			0	0	392.1	414.5	34.5	31.7	(426.6)	(446.2)
Other current liabilities	32.1	33.2			3.7	0.8	25.3	30.2	3.1	2.2	0	0
Total current liabilities	222.9	213.8			17.4	20.4	578.9	594.9	53.2	44.7	(426.6)	(446.2)
Long-term debt, net of current portion	651.0	653.6			645.7	647.8	0	0	5.3	5.8	0	0
Amounts due to affiliated companies	0	0			0	0	0	0	26.0	26.0	(26.0)	(26.0)
Other long-term liabilities	33.7	36.0			5.2	7.7	28.4	26.3	0.1	2.0	0	0
Total liabilities	907.6	903.4			668.3	675.9	607.3	621.2	84.6	78.5	(452.6)	(472.2)
Total stockholders' equity	391.5	312.6			391.5	312.6	488.8	472.3	11.4	8.3	(500.2)	(480.6)
Total liabilities and stockholders' equity	$ 1,299.1	$ 1,216.0			$ 1,059.8	$ 988.5	$ 1,096.1	$ 1,093.5	$ 96.0	$ 86.8	$ (952.8)	$ (952.8)