Guarantor Financial Statements - Condensed Consolidating Statement of Operations and Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013
Condensed Financial Statements, Captions [Line Items]
Net Sales	$ 642.9	$ 589.2	$ 1,909.3	$ 1,739.0
Cost of products sold	452.9	415.5	1,355.4	1,236.9
Gross profit	190.0	173.7	553.9	502.1
Selling, general and administrative expense, net	141.7	128.0	416.0	386.5
Impairment of long-lived assets and goodwill ($4.4 million)	0	0	80.4	0
Amortization of intangible assets	14.9	13.2	43.7	38.1
Operating earnings	33.4	32.5	13.8	77.5
Net interest expense	(27.3)	(24.8)	(78.0)	(74.1)
Loss from debt retirement	(0.5)	0	(2.3)	0
Earnings (loss) before provision (benefit) for income taxes	5.6	7.7	(66.5)	3.4
Charges and allocations to subsidiaries and equity in subsidiaries' earnings (loss) before income taxes	0	0	0	0
Earnings (loss) before provision (benefit) for income taxes	5.6	7.7	(66.5)	3.4
Provision (benefit) for income taxes	1.0	3.5	(16.3)	2.8
Net earnings (loss)	4.6	4.2	(50.2)	0.6
Comprehensive (loss) income	0.8	7.0	(54.7)	(1.2)
Nortek [Member]
Condensed Financial Statements, Captions [Line Items]
Net Sales	0	0	0	0
Cost of products sold	0	0	0	0
Gross profit	0	0	0	0
Selling, general and administrative expense, net	14.8	13.1	48.5	46.1
Impairment of long-lived assets and goodwill ($4.4 million)			0
Amortization of intangible assets	0	0	0	0
Operating earnings	(14.8)	(13.1)	(48.5)	(46.1)
Net interest expense	(26.4)	(24.2)	(76.1)	(72.2)
Loss from debt retirement	(0.5)		(2.3)
Earnings (loss) before provision (benefit) for income taxes	(41.7)	(37.3)	(126.9)	(118.3)
Charges and allocations to subsidiaries and equity in subsidiaries' earnings (loss) before income taxes	47.3	45.0	60.4	121.7
Earnings (loss) before provision (benefit) for income taxes	5.6	7.7	(66.5)	3.4
Provision (benefit) for income taxes	1.0	3.5	(16.3)	2.8
Net earnings (loss)	4.6	4.2	(50.2)	0.6
Comprehensive (loss) income	0.8	7.0	(54.7)	(1.2)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net Sales	545.3	510.6	1,631.4	1,489.3
Cost of products sold	387.0	366.4	1,163.8	1,070.4
Gross profit	158.3	144.2	467.6	418.9
Selling, general and administrative expense, net	99.1	92.9	292.1	272.5
Impairment of long-lived assets and goodwill ($4.4 million)			70.1
Amortization of intangible assets	13.8	12.7	40.9	36.6
Operating earnings	45.4	38.6	64.5	109.8
Net interest expense	(0.9)	(0.6)	(1.8)	(1.9)
Loss from debt retirement	0		0
Earnings (loss) before provision (benefit) for income taxes	44.5	38.0	62.7	107.9
Charges and allocations to subsidiaries and equity in subsidiaries' earnings (loss) before income taxes	(18.8)	(16.4)	(58.3)	(51.3)
Earnings (loss) before provision (benefit) for income taxes	25.7	21.6	4.4	56.6
Provision (benefit) for income taxes	8.7	7.4	3.9	15.6
Net earnings (loss)	17.0	14.2	0.5	41.0
Comprehensive (loss) income	17.0	14.2	0.5	41.1
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net Sales	207.4	185.8	640.1	550.7
Cost of products sold	176.5	156.4	552.5	465.4
Gross profit	30.9	29.4	87.6	85.3
Selling, general and administrative expense, net	27.8	22.0	75.4	67.9
Impairment of long-lived assets and goodwill ($4.4 million)			10.3
Amortization of intangible assets	1.3	0.7	3.4	2.1
Operating earnings	1.8	6.7	(1.5)	15.3
Net interest expense	0	0	(0.1)	0
Loss from debt retirement	0		0
Earnings (loss) before provision (benefit) for income taxes	1.8	6.7	(1.6)	15.3
Charges and allocations to subsidiaries and equity in subsidiaries' earnings (loss) before income taxes	(0.3)	0.3	0.2	0.8
Earnings (loss) before provision (benefit) for income taxes	1.5	7.0	(1.4)	16.1
Provision (benefit) for income taxes	2.2	3.8	3.9	7.8
Net earnings (loss)	(0.7)	3.2	(5.3)	8.3
Comprehensive (loss) income	(3.8)	6.0	(9.1)	6.0
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net Sales	(109.8)	(107.2)	(362.2)	(301.0)
Cost of products sold	(110.6)	(107.3)	(360.9)	(298.9)
Gross profit	0.8	0.1	(1.3)	(2.1)
Selling, general and administrative expense, net	0	0	0	0
Impairment of long-lived assets and goodwill ($4.4 million)			0
Amortization of intangible assets	(0.2)	(0.2)	(0.6)	(0.6)
Operating earnings	1.0	0.3	(0.7)	(1.5)
Net interest expense	0	0	0	0
Loss from debt retirement	0		0
Earnings (loss) before provision (benefit) for income taxes	1.0	0.3	(0.7)	(1.5)
Charges and allocations to subsidiaries and equity in subsidiaries' earnings (loss) before income taxes	(28.2)	(28.9)	(2.3)	(71.2)
Earnings (loss) before provision (benefit) for income taxes	(27.2)	(28.6)	(3.0)	(72.7)
Provision (benefit) for income taxes	(10.9)	(11.2)	(7.8)	(23.4)
Net earnings (loss)	(16.3)	(17.4)	4.8	(49.3)
Comprehensive (loss) income	$ (13.2)	$ (20.2)	$ 8.6	$ (47.1)