Consolidating Financial Information - Consolidating Balance Sheets (Details 1) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Consolidated Balance Sheets [Abstract]
Cash and cash equivalents	$ 905.1	$ 1,035.3	$ 432.0	$ 381.6
Receivables, less allowances	916.1	795.9
Inventories	505.4	438.9
Current discontinued operations receivable	2.9	13.0
Other current assets	252.7	207.5
Total current assets	2,582.2	2,490.6
Property, plant and equipment, less accumulated depreciation	611.1	608.3
Investment in Apex Tool Group, LLC	533.1	511.3
Investment in subsidiaries	0	0
Investment in parent	0	0
Intercompany accounts receivable	0	0
Intercompany notes receivable	0	0
Goodwill	2,401.0	2,356.5
Other intangible assets, less accumulated amortization	330.6	333.6
Long-term discontinued operations receivable	7.1	150.6
Other noncurrent assets	174.5	217.7
Total assets	6,639.6	6,668.6
Short-term debt	15.8	7.7
Accounts payable	491.9	462.6
Accrued liabilities	480.8	510.1
Current discontinued operations liability	9.4	45.4
Current maturities of long-term debt		0.6
Total current liabilities	997.9	1,026.4
Long-term debt	1,419.1	1,420.4
Intercompany accounts payable	0	0
Intercompany notes payable	0	0
Long-term discontinued operations liability	40.5	701.7
Other long-term liabilities	473.6	314.0
Total liabilities	2,931.1	3,462.5
Common stock	1.7	1.7
Subsidiary preferred stock	0	0
Subsidiary common stock	0	0
Capital in excess of par value	0	0
Retained earnings	4,154.5	3,658.7
Treasury stock	(329.1)	(288.6)
Accumulated other nonowner changes in equity	(118.6)	(165.7)
Total shareholders' equity	3,708.5	3,206.1
Total liabilities and shareholders' equity	6,639.6	6,668.6
Cooper Industries plc [Member]
Consolidated Balance Sheets [Abstract]
Cash and cash equivalents	47.4	63.2	47.1	146.0
Receivables, less allowances	0.2	0
Inventories	0	0
Current discontinued operations receivable	0	0
Other current assets	0.2	0.6
Total current assets	47.8	63.8
Property, plant and equipment, less accumulated depreciation	0	0
Investment in Apex Tool Group, LLC	0	0
Investment in subsidiaries	4,456.2	3,035.5
Investment in parent	0	0
Intercompany accounts receivable	80.1	71.9
Intercompany notes receivable	0	40.0
Goodwill	0	0
Other intangible assets, less accumulated amortization	0	0
Long-term discontinued operations receivable	0	0
Other noncurrent assets	0.5	0
Total assets	4,584.6	3,211.2
Short-term debt	0	0
Accounts payable	48.0	44.7
Accrued liabilities	1.0	1.2
Current discontinued operations liability	0	0
Current maturities of long-term debt		0
Total current liabilities	49.0	45.9
Long-term debt	0	0
Intercompany accounts payable	0	0
Intercompany notes payable	1,331.7	419.7
Long-term discontinued operations liability	0	0
Other long-term liabilities	0	0
Total liabilities	1,380.7	465.6
Common stock	1.7	1.7
Subsidiary preferred stock	0	0
Subsidiary common stock	0	0
Capital in excess of par value	2,926.1	2,811.0
Retained earnings	514.8	145.0
Treasury stock	(329.1)	(288.6)
Accumulated other nonowner changes in equity	90.4	76.5
Total shareholders' equity	3,203.9	2,745.6
Total liabilities and shareholders' equity	4,584.6	3,211.2
Cooper US, Inc. [Member]
Consolidated Balance Sheets [Abstract]
Cash and cash equivalents	641.1	36.8	80.1	27.9
Receivables, less allowances	1.9	2.5
Inventories	0	0
Current discontinued operations receivable	0	0
Other current assets	78.7	72.4
Total current assets	721.7	111.7
Property, plant and equipment, less accumulated depreciation	39.9	42.1
Investment in Apex Tool Group, LLC	0	0
Investment in subsidiaries	3,268.3	2,923.6
Investment in parent	3,428.0	3,428.1
Intercompany accounts receivable	0	0
Intercompany notes receivable	1,632.7	1,674.8
Goodwill	0	0
Other intangible assets, less accumulated amortization	0	0
Long-term discontinued operations receivable	0	0
Other noncurrent assets	(3.9)	13.1
Total assets	9,086.7	8,193.4
Short-term debt	7.3	0
Accounts payable	22.9	20.3
Accrued liabilities	60.5	66.3
Current discontinued operations liability	0	0
Current maturities of long-term debt		0
Total current liabilities	90.7	86.6
Long-term debt	1,419.1	1,418.5
Intercompany accounts payable	3,210.5	3,290.2
Intercompany notes payable	2,285.2	1,587.2
Long-term discontinued operations liability	0	0
Other long-term liabilities	90.2	103.6
Total liabilities	7,095.7	6,486.1
Common stock	0	0
Subsidiary preferred stock	0	0
Subsidiary common stock	0	0
Capital in excess of par value	781.0	770.4
Retained earnings	1,322.5	1,049.4
Treasury stock	0	0
Accumulated other nonowner changes in equity	(112.5)	(112.5)
Total shareholders' equity	1,991.0	1,707.3
Total liabilities and shareholders' equity	9,086.7	8,193.4
Guarantors [Member]
Consolidated Balance Sheets [Abstract]
Cash and cash equivalents	0	2.6	(3.9)	0.3
Receivables, less allowances	248.4	218.7
Inventories	274.6	234.7
Current discontinued operations receivable	0	0
Other current assets	34.9	30.7
Total current assets	557.9	486.7
Property, plant and equipment, less accumulated depreciation	314.5	316.8
Investment in Apex Tool Group, LLC	0	0
Investment in subsidiaries	5,117.4	4,608.9
Investment in parent	0	0
Intercompany accounts receivable	1,984.0	1,974.1
Intercompany notes receivable	3,348.3	3,348.3
Goodwill	1,288.3	1,288.3
Other intangible assets, less accumulated amortization	86.5	85.7
Long-term discontinued operations receivable	0	0
Other noncurrent assets	3.2	(178.2)
Total assets	12,700.1	11,930.6
Short-term debt	0	0
Accounts payable	205.3	201.8
Accrued liabilities	193.5	210.4
Current discontinued operations liability	0	0
Current maturities of long-term debt		0
Total current liabilities	398.8	412.2
Long-term debt	0	0
Intercompany accounts payable	0	0
Intercompany notes payable	4,436.3	4,436.2
Long-term discontinued operations liability	0	0
Other long-term liabilities	209.3	54.5
Total liabilities	5,044.4	4,902.9
Common stock	0	0
Subsidiary preferred stock	2,872.0	2,872.1
Subsidiary common stock	9.2	9.2
Capital in excess of par value	1,947.3	1,936.7
Retained earnings	2,853.5	2,288.5
Treasury stock	0	0
Accumulated other nonowner changes in equity	(26.3)	(78.8)
Total shareholders' equity	7,655.7	7,027.7
Total liabilities and shareholders' equity	12,700.1	11,930.6
Other Subsidiaries [Member]
Consolidated Balance Sheets [Abstract]
Cash and cash equivalents	216.6	932.7	308.7	207.4
Receivables, less allowances	665.6	574.7
Inventories	230.8	204.2
Current discontinued operations receivable	2.9	13.0
Other current assets	138.9	103.8
Total current assets	1,254.8	1,828.4
Property, plant and equipment, less accumulated depreciation	256.7	249.4
Investment in Apex Tool Group, LLC	533.1	511.3
Investment in subsidiaries	1,014.9	741.6
Investment in parent	312.7	312.7
Intercompany accounts receivable	1,146.4	1,244.2
Intercompany notes receivable	7,004.6	5,394.7
Goodwill	1,112.7	1,068.2
Other intangible assets, less accumulated amortization	244.1	247.9
Long-term discontinued operations receivable	7.1	150.6
Other noncurrent assets	174.7	382.8
Total assets	13,061.8	12,131.8
Short-term debt	8.5	7.7
Accounts payable	215.7	195.8
Accrued liabilities	227.4	233.6
Current discontinued operations liability	9.4	45.4
Current maturities of long-term debt		0.6
Total current liabilities	461.0	483.1
Long-term debt	0	1.9
Intercompany accounts payable	0	0
Intercompany notes payable	3,932.4	4,014.7
Long-term discontinued operations liability	40.5	701.7
Other long-term liabilities	174.1	155.9
Total liabilities	4,608.0	5,357.3
Common stock	0	0
Subsidiary preferred stock	335.1	335.1
Subsidiary common stock	257.8	257.8
Capital in excess of par value	3,046.2	2,106.3
Retained earnings	4,828.6	4,133.5
Treasury stock	0	0
Accumulated other nonowner changes in equity	(13.9)	(58.2)
Total shareholders' equity	8,453.8	6,774.5
Total liabilities and shareholders' equity	13,061.8	12,131.8
Consolidating Adjustments [Member]
Consolidated Balance Sheets [Abstract]
Cash and cash equivalents	0	0	0	0
Receivables, less allowances	0	0
Inventories	0	0
Current discontinued operations receivable	0	0
Other current assets	0	0
Total current assets	0	0
Property, plant and equipment, less accumulated depreciation	0	0
Investment in Apex Tool Group, LLC	0	0
Investment in subsidiaries	(13,856.8)	(11,309.6)
Investment in parent	(3,740.7)	(3,740.8)
Intercompany accounts receivable	3,210.5	(3,290.2)
Intercompany notes receivable	(11,985.6)	(10,457.8)
Goodwill	0	0
Other intangible assets, less accumulated amortization	0	0
Long-term discontinued operations receivable	0	0
Other noncurrent assets	0	0
Total assets	(32,793.6)	(28,798.4)
Short-term debt	0	0
Accounts payable	0	0
Accrued liabilities	(1.6)	(1.4)
Current discontinued operations liability	0	0
Current maturities of long-term debt		0
Total current liabilities	(1.6)	(1.4)
Long-term debt	0	0
Intercompany accounts payable	(3,210.5)	(3,290.2)
Intercompany notes payable	(11,985.6)	(10,457.8)
Long-term discontinued operations liability	0	0
Other long-term liabilities	0	0
Total liabilities	(15,197.7)	(13,749.4)
Common stock	0	0
Subsidiary preferred stock	(3,207.1)	(3,207.2)
Subsidiary common stock	(267.0)	(267.0)
Capital in excess of par value	(8,700.6)	(7,624.4)
Retained earnings	(5,364.9)	(3,957.7)
Treasury stock	0	0
Accumulated other nonowner changes in equity	(56.3)	7.3
Total shareholders' equity	(17,595.9)	(15,049.0)
Total liabilities and shareholders' equity	$ (32,793.6)	$ (28,798.4)