Guarantor Financial Statements - Condensed Consolidating Balance Sheet (Details) - USD ($) $ in Millions		Sep. 26, 2015	Dec. 31, 2014	Sep. 27, 2014	Dec. 31, 2013
Current Assets:
Unrestricted cash and cash equivalents		$ 27.8	$ 58.4	$ 66.2	$ 80.9
Restricted cash		0.2	0.6
Accounts receivable, less allowances		347.6	324.9
Intercompany receivables		0.0	0.0
Inventories, net		385.6	374.3
Prepaid expenses		21.2	18.4
Other current assets		21.2	18.1
Deferred tax assets		43.7	28.1
Total current assets		847.3	822.8
Property and Equipment, at Cost:
Total property and equipment, net		222.2	238.0
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries		0.0	0.0
Goodwill	[1]	504.3	474.3
Intangible assets, less accumulated amortization		624.6	642.6
Deferred tax asset		0.0	0.0
Other assets		28.3	31.4
Total other long-term assets		1,157.2	1,148.3
Total Assets		2,226.7	2,209.1
Current Liabilities:
Short-term bank obligations		0.5	0.6
Current maturities of long-term debt		7.3	6.3
Accounts payable		271.7	288.8
Accrued expenses, taxes, and deferred revenue		240.1	222.4
Current deferred taxes		0.0	0.0
Intercompany payables		0.0	0.0
Total current liabilities		519.6	518.1
Other Liabilities:
Deferred income taxes		122.9	123.5
Other long-term liabilities		181.8	185.9
Long-term intercompany payables		0.0	0.0
Total other long-term liabilities		304.7	309.4
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities		1,395.6	1,339.4
Stockholders' investment (deficit)		6.8	42.2
Total Liabilities and Stockholders' Investment		2,226.7	2,209.1
Eliminations
Current Assets:
Unrestricted cash and cash equivalents		0.0	0.0
Restricted cash		0.0	0.0
Accounts receivable, less allowances		0.0	0.0
Intercompany receivables		(98.2)	(84.0)
Inventories, net		(6.9)	(7.4)
Prepaid expenses		0.0	0.0
Other current assets		0.0	0.0
Deferred tax assets		(0.5)	(1.1)
Total current assets		(105.6)	(92.5)
Property and Equipment, at Cost:
Total property and equipment, net		0.0	0.0
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries		(1,803.0)	(1,792.1)
Goodwill		0.0	0.0
Intangible assets, less accumulated amortization		(9.0)	(9.6)
Deferred tax asset		(14.2)	(13.9)
Other assets		0.0	0.0
Total other long-term assets		(1,826.2)	(1,815.6)
Total Assets		(1,931.8)	(1,908.1)
Current Liabilities:
Short-term bank obligations		0.0	0.0
Current maturities of long-term debt		0.0	0.0
Accounts payable		0.0	0.0
Accrued expenses, taxes, and deferred revenue		0.0	0.0
Current deferred taxes		(0.5)	(1.1)
Intercompany payables		(98.2)	(84.0)
Total current liabilities		(98.7)	(85.1)
Other Liabilities:
Deferred income taxes		(16.9)	(16.7)
Other long-term liabilities		0.0	0.0
Long-term intercompany payables		(102.6)	(119.6)
Total other long-term liabilities		(119.5)	(136.3)
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities		0.0	0.0
Stockholders' investment (deficit)		(1,713.6)	(1,686.7)
Total Liabilities and Stockholders' Investment		(1,931.8)	(1,908.1)
Nortek | Reportable Legal Entities
Current Assets:
Unrestricted cash and cash equivalents		4.5	17.5	21.3	23.2
Restricted cash		0.1	0.2
Accounts receivable, less allowances		0.0	0.0
Intercompany receivables		0.7	3.2
Inventories, net		0.0	0.0
Prepaid expenses		3.0	2.5
Other current assets		1.2	0.0
Deferred tax assets		17.1	4.1
Total current assets		26.6	27.5
Property and Equipment, at Cost:
Total property and equipment, net		11.4	11.9
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries		1,445.1	1,376.2
Goodwill		0.0	0.0
Intangible assets, less accumulated amortization		0.0	0.0
Deferred tax asset		14.2	13.9
Other assets		16.1	19.1
Total other long-term assets		1,475.4	1,409.2
Total Assets		1,513.4	1,448.6
Current Liabilities:
Short-term bank obligations		0.0	0.0
Current maturities of long-term debt		6.1	3.8
Accounts payable		4.7	2.4
Accrued expenses, taxes, and deferred revenue		53.6	32.7
Current deferred taxes		0.0	0.0
Intercompany payables		0.0	0.0
Total current liabilities		64.4	38.9
Other Liabilities:
Deferred income taxes		0.0	0.0
Other long-term liabilities		53.2	34.6
Long-term intercompany payables		0.0	0.0
Total other long-term liabilities		53.2	34.6
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities		1,389.0	1,332.9
Stockholders' investment (deficit)		6.8	42.2
Total Liabilities and Stockholders' Investment		1,513.4	1,448.6
Guarantor Subsidiaries | Reportable Legal Entities
Current Assets:
Unrestricted cash and cash equivalents		1.6	5.1	18.1	20.0
Restricted cash		0.1	0.4
Accounts receivable, less allowances		286.3	257.3
Intercompany receivables		0.0	0.0
Inventories, net		309.0	303.5
Prepaid expenses		11.5	10.5
Other current assets		10.3	7.2
Deferred tax assets		27.1	25.1
Total current assets		645.9	609.1
Property and Equipment, at Cost:
Total property and equipment, net		156.9	163.0
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries		357.9	415.9
Goodwill		464.3	434.4
Intangible assets, less accumulated amortization		582.1	596.5
Deferred tax asset		0.0	0.0
Other assets		11.4	11.4
Total other long-term assets		1,415.7	1,458.2
Total Assets		2,218.5	2,230.3
Current Liabilities:
Short-term bank obligations		0.0	0.0
Current maturities of long-term debt		1.2	2.5
Accounts payable		134.7	157.0
Accrued expenses, taxes, and deferred revenue		143.7	145.7
Current deferred taxes		0.0	0.0
Intercompany payables		98.2	84.0
Total current liabilities		377.8	389.2
Other Liabilities:
Deferred income taxes		125.3	126.4
Other long-term liabilities		104.3	125.1
Long-term intercompany payables		0.0	0.0
Total other long-term liabilities		229.6	251.5
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities		4.8	6.5
Stockholders' investment (deficit)		1,606.3	1,583.1
Total Liabilities and Stockholders' Investment		2,218.5	2,230.3
Non-Guarantor Subsidiaries | Reportable Legal Entities
Current Assets:
Unrestricted cash and cash equivalents		21.7	35.8	$ 26.8	$ 37.7
Restricted cash		0.0	0.0
Accounts receivable, less allowances		61.3	67.6
Intercompany receivables		97.5	80.8
Inventories, net		83.5	78.2
Prepaid expenses		6.7	5.4
Other current assets		9.7	10.9
Deferred tax assets		0.0	0.0
Total current assets		280.4	278.7
Property and Equipment, at Cost:
Total property and equipment, net		53.9	63.1
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries		0.0	0.0
Goodwill		40.0	39.9
Intangible assets, less accumulated amortization		51.5	55.7
Deferred tax asset		0.0	0.0
Other assets		0.8	0.9
Total other long-term assets		92.3	96.5
Total Assets		426.6	438.3
Current Liabilities:
Short-term bank obligations		0.5	0.6
Current maturities of long-term debt		0.0	0.0
Accounts payable		132.3	129.4
Accrued expenses, taxes, and deferred revenue		42.8	44.0
Current deferred taxes		0.5	1.1
Intercompany payables		0.0	0.0
Total current liabilities		176.1	175.1
Other Liabilities:
Deferred income taxes		14.5	13.8
Other long-term liabilities		24.3	26.2
Long-term intercompany payables		102.6	119.6
Total other long-term liabilities		141.4	159.6
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities		1.8	0.0
Stockholders' investment (deficit)		107.3	103.6
Total Liabilities and Stockholders' Investment		$ 426.6	$ 438.3

[1] The CAS and combined AVC reporting units did not have goodwill for any periods presented.