Financial Statements of Parent Company Guarantor - Condensed Consolidating Balance Sheet (Detail) (USD $) In Millions, unless otherwise specified	Jun. 29, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2011
Current assets
Cash and cash equivalents	$ 253.1	$ 261.3	$ 60.6	$ 50.1
Accounts and notes receivable, net	1,305.5	1,293.9
Inventories	1,318.3	1,379.0
Other current assets	339.6	325.5
Total current assets	3,216.5	3,259.7
Property, plant and equipment, net	1,186.1	1,209.8
Other assets
Goodwill	4,964.6	4,983.5
Intangibles, net	1,836.6	1,926.9
Other non-current assets	462.8	489.3
Total other assets	7,264.0	7,399.7
Total assets	11,666.6	11,869.2
Current liabilities
Current maturities of long-term debt and short-term borrowings	2.9	3.1
Accounts payable	593.9	568.2
Employee compensation and benefits	292.6	295.5
Other current liabilities	797.4	758.9
Total current liabilities	1,686.8	1,625.7
Other liabilities
Long-term debt	2,737.4	2,454.3
Pension and other post-retirement compensation and benefits	374.5	378.1
Deferred tax liabilities	498.0	490.3
Other non-current liabilities	427.0	441.6
Total liabilities	5,723.7	5,390.0
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	5,826.0	6,362.7
Noncontrolling interest	116.9	116.5
Total equity	5,942.9	6,479.2	2,119.8	2,047.4
Total liabilities and equity	11,666.6	11,869.2
Parent Company Guarantor
Current assets
Cash and cash equivalents		0
Accounts and notes receivable, net	0.2	20.2
Inventories		0
Other current assets	0.5	85.8
Total current assets	0.7	106.0
Property, plant and equipment, net		0
Other assets
Investments in subsidiaries	6,266.1	6,491.9
Other non-current assets	31.0	31.0
Total other assets	6,297.1	6,522.9
Total assets	6,297.8	6,628.9
Current liabilities
Current maturities of long-term debt and short-term borrowings		0
Accounts payable	220.0	54.2
Other current liabilities	220.8	181.0
Total current liabilities	440.8	235.2
Other liabilities
Other non-current liabilities	31.0	31.0
Total liabilities	471.8	266.2
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	5,826.0	6,362.7
Total equity	5,826.0	6,362.7
Total liabilities and equity	6,297.8	6,628.9
Subsidiary Issuer
Current assets
Cash and cash equivalents	3.5	0
Accounts and notes receivable, net	16.3	1,458.3
Inventories		0
Other current assets		0
Total current assets	19.8	1,458.3
Property, plant and equipment, net		0
Other assets
Investments in subsidiaries	7,711.5	7,470.1
Other non-current assets	1,690.3	6.9
Total other assets	9,401.8	7,477.0
Total assets	9,421.6	8,935.3
Current liabilities
Current maturities of long-term debt and short-term borrowings		0
Accounts payable	0	1.8
Other current liabilities	13.6	11.4
Total current liabilities	13.6	13.2
Other liabilities
Long-term debt	2,563.6	2,297.7
Total liabilities	2,577.2	2,310.9
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	6,844.4	6,624.4
Total equity	6,844.4	6,624.4
Total liabilities and equity	9,421.6	8,935.3
Non-Guarantor Subsidiaries
Current assets
Cash and cash equivalents	249.6	261.3
Accounts and notes receivable, net	1,525.6	1,350.0
Inventories	1,318.3	1,379.0
Other current assets	339.1	324.1
Total current assets	3,432.6	3,314.4
Property, plant and equipment, net	1,186.1	1,209.8
Other assets
Goodwill	4,964.6	4,983.5
Intangibles, net	1,836.6	1,926.9
Other non-current assets	455.1	482.4
Total other assets	7,256.3	7,392.8
Total assets	11,875.0	11,917.0
Current liabilities
Current maturities of long-term debt and short-term borrowings	2.9	3.1
Accounts payable	594.1	588.5
Employee compensation and benefits	292.6	295.5
Other current liabilities	563.0	650.9
Total current liabilities	1,452.6	1,538.0
Other liabilities
Long-term debt	1,872.8	1,614.9
Pension and other post-retirement compensation and benefits	374.5	378.1
Deferred tax liabilities	498.0	490.3
Other non-current liabilities	427.0	441.6
Total liabilities	4,624.9	4,462.9
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	7,133.2	7,337.6
Noncontrolling interest	116.9	116.5
Total equity	7,250.1	7,454.1
Total liabilities and equity	11,875.0	11,917.0
Eliminations
Current assets
Accounts and notes receivable, net	(236.6)	(1,534.6)
Other current assets		(84.4)
Total current assets	(236.6)	(1,619.0)
Other assets
Investments in subsidiaries	(13,977.6)	(13,962.0)
Other non-current assets	(1,713.6)	(31.0)
Total other assets	(15,691.2)	(13,993.0)
Total assets	(15,927.8)	(15,612.0)
Current liabilities
Accounts payable	(220.2)	(76.3)
Other current liabilities		(84.4)
Total current liabilities	(220.2)	(160.7)
Other liabilities
Long-term debt	(1,699.0)	(1,458.3)
Other non-current liabilities	(31.0)	(31.0)
Total liabilities	(1,950.2)	(1,650.0)
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	(13,977.6)	(13,962.0)
Total equity	(13,977.6)	(13,962.0)
Total liabilities and equity	$ (15,927.8)	$ (15,612.0)