GUARANTOR FINANCIAL STATEMENTS - Condensed Consolidating Balance Sheet (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Current Assets:
Unrestricted cash and cash equivalents	$ 58.4		$ 80.9		$ 144.7		$ 58.2
Restricted cash	0.6		2.9
Accounts receivable, less allowances	324.9		276.4
Intercompany receivables	0		0
Inventories, net	374.3		270.5
Prepaid expenses	18.4		20.2
Other current assets	18.1		19.4
Deferred tax assets	28.1		29.7
Total current assets	822.8		700.0
Property and Equipment, at Cost:
Total property and equipment, net	238.0		232.4
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries	0		0
Goodwill	474.3	[1]	373.5	[1]	307.6	[1]
Intangible assets, less accumulated amortization	642.6		648.9
Deferred tax asset	0		0
Other assets	31.4		36.1
Total other long-term assets	1,148.3		1,058.5
Total Assets	2,209.1		1,990.9
Current Liabilities:
Short-term bank obligations	0.6		0.7
Current maturities of long-term debt	6.3		2.8
Accounts payable	288.8		214.7
Accrued expenses and taxes	222.4		231.5
Current deferred taxes	0		0
Intercompany payables	0		0
Total current liabilities	518.1		449.7
Other Liabilities:
Deferred income taxes	123.5		159.1
Other long-term liabilities	185.9		188.9
Long-term intercompany payables	0		0
Total other long-term liabilities	309.4		348.0
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities	1,339.4		1,093.3
Stockholders' investment (deficit)	42.2		99.9		94.2		80.4
Total Liabilities and Stockholders' Investment	2,209.1		1,990.9
Reportable Legal Entities [Member] | Nortek [Member]
Current Assets:
Unrestricted cash and cash equivalents	17.5		23.2		94.9		17.8
Restricted cash	0.2		2.7
Accounts receivable, less allowances	0		0.1
Intercompany receivables	3.2		1.4
Inventories, net	0		0
Prepaid expenses	2.5		3.2
Other current assets	0		0.1
Deferred tax assets	4.1		4.8
Total current assets	27.5		35.5
Property and Equipment, at Cost:
Total property and equipment, net	11.9		7.0
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries	1,376.2		1,180.7
Goodwill	0		0
Intangible assets, less accumulated amortization	0		0
Deferred tax asset	13.9		10.2
Other assets	19.1		20.3
Total other long-term assets	1,409.2		1,211.2
Total Assets	1,448.6		1,253.7
Current Liabilities:
Short-term bank obligations	0		0
Current maturities of long-term debt	3.8		0.3
Accounts payable	2.4		2.3
Accrued expenses and taxes	32.7		36.2
Current deferred taxes	0		0
Intercompany payables	0		0
Total current liabilities	38.9		38.8
Other Liabilities:
Deferred income taxes	0		0
Other long-term liabilities	34.6		31.7
Long-term intercompany payables	0		0
Total other long-term liabilities	34.6		31.7
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities	1,332.9		1,083.3
Stockholders' investment (deficit)	42.2		99.9
Total Liabilities and Stockholders' Investment	1,448.6		1,253.7
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Current Assets:
Unrestricted cash and cash equivalents	5.1		20.0		13.1		9.3
Restricted cash	0.4		0.1
Accounts receivable, less allowances	257.3		219.2
Intercompany receivables	0		0
Inventories, net	303.5		204.5
Prepaid expenses	10.5		11.0
Other current assets	7.2		6.5
Deferred tax assets	25.1		26.3
Total current assets	609.1		487.6
Property and Equipment, at Cost:
Total property and equipment, net	163.0		157.4
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries	415.9		418.6
Goodwill	434.4		357.8
Intangible assets, less accumulated amortization	596.5		627.1
Deferred tax asset	0		0
Other assets	11.4		14.6
Total other long-term assets	1,458.2		1,418.1
Total Assets	2,230.3		2,063.1
Current Liabilities:
Short-term bank obligations	0		0
Current maturities of long-term debt	2.5		2.5
Accounts payable	157.0		103.7
Accrued expenses and taxes	145.7		152.4
Current deferred taxes	0		0
Intercompany payables	84.0		61.9
Total current liabilities	389.2		320.5
Other Liabilities:
Deferred income taxes	126.4		163.8
Other long-term liabilities	125.1		135.6
Long-term intercompany payables	0		0
Total other long-term liabilities	251.5		299.4
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities	6.5		10.0
Stockholders' investment (deficit)	1,583.1		1,433.2
Total Liabilities and Stockholders' Investment	2,230.3		2,063.1
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Current Assets:
Unrestricted cash and cash equivalents	35.8		37.7		36.7		31.1
Restricted cash	0		0.1
Accounts receivable, less allowances	67.6		57.1
Intercompany receivables	80.8		60.5
Inventories, net	78.2		72.0
Prepaid expenses	5.4		6.0
Other current assets	10.9		12.8
Deferred tax assets	0		0
Total current assets	278.7		246.2
Property and Equipment, at Cost:
Total property and equipment, net	63.1		68.0
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries	0		0
Goodwill	39.9		15.7
Intangible assets, less accumulated amortization	55.7		32.2
Deferred tax asset	0		0
Other assets	0.9		1.2
Total other long-term assets	96.5		49.1
Total Assets	438.3		363.3
Current Liabilities:
Short-term bank obligations	0.6		0.7
Current maturities of long-term debt	0		0
Accounts payable	129.4		108.7
Accrued expenses and taxes	44.0		42.9
Current deferred taxes	1.1		1.4
Intercompany payables	0		0
Total current liabilities	175.1		153.7
Other Liabilities:
Deferred income taxes	13.8		7.7
Other long-term liabilities	26.2		21.6
Long-term intercompany payables	119.6		49.4
Total other long-term liabilities	159.6		78.7
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities	0		0
Stockholders' investment (deficit)	103.6		130.9
Total Liabilities and Stockholders' Investment	438.3		363.3
Eliminations [Member]
Current Assets:
Unrestricted cash and cash equivalents	0		0
Restricted cash	0		0
Accounts receivable, less allowances	0		0
Intercompany receivables	(84.0)		(61.9)
Inventories, net	(7.4)		(6.0)
Prepaid expenses	0		0
Other current assets	0		0
Deferred tax assets	(1.1)		(1.4)
Total current assets	(92.5)		(69.3)
Property and Equipment, at Cost:
Total property and equipment, net	0		0
Other Long-term Assets:
Investment in subsidiaries and long-term receivable from (to) subsidiaries	(1,792.1)		(1,599.3)
Goodwill	0		0
Intangible assets, less accumulated amortization	(9.6)		(10.4)
Deferred tax asset	(13.9)		(10.2)
Other assets	0		0
Total other long-term assets	(1,815.6)		(1,619.9)
Total Assets	(1,908.1)		(1,689.2)
Current Liabilities:
Short-term bank obligations	0		0
Current maturities of long-term debt	0		0
Accounts payable	0		0
Accrued expenses and taxes	0		0
Current deferred taxes	(1.1)		(1.4)
Intercompany payables	(84.0)		(61.9)
Total current liabilities	(85.1)		(63.3)
Other Liabilities:
Deferred income taxes	(16.7)		(12.4)
Other long-term liabilities	0		0
Long-term intercompany payables	(119.6)		(49.4)
Total other long-term liabilities	(136.3)		(61.8)
Notes, Mortgage Notes and Obligations Payable, Less Current Maturities	0		0
Stockholders' investment (deficit)	(1,686.7)		(1,564.1)
Total Liabilities and Stockholders' Investment	$ (1,908.1)		$ (1,689.2)

[1] The CAS reporting unit did not have goodwill in any period presented.