Financial Statements of Parent Company Guarantor - Condensed Consolidating Balance Sheet (Detail) (USD $) In Millions, unless otherwise specified	Sep. 27, 2014	Dec. 31, 2013	Sep. 28, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 156.6	$ 256.0	$ 219.2	$ 237.4
Accounts and notes receivable, net	1,180.9	1,285.0
Inventories	1,199.4	1,195.1
Other current assets	386.3	361.6
Assets of Disposal Group, Including Discontinued Operation, Current	129.2	134.4
Total current assets	3,052.4	3,232.1
Property, plant and equipment, net	990.8	1,044.3
Other assets
Goodwill	4,792.6	4,860.7
Intangibles, net	1,648.6	1,749.9
Other non-current assets	406.3	390.0
Assets of Disposal Group, Including Discontinued Operation, Noncurrent	36.2	466.3
Total other assets	6,883.7	7,466.9
Total assets	10,926.9	11,743.3
Current liabilities
Current maturities of long-term debt and short-term borrowings	2.5	2.5
Accounts payable	527.2	576.9
Employee compensation and benefits	287.4	312.4
Other current liabilities	791.1	645.9
Liabilities of Disposal Group, Including Discontinued Operation, Current	60.5	72.5
Total current liabilities	1,668.7	1,610.2
Other liabilities
Long-term debt	2,960.7	2,547.9
Pension and other post-retirement compensation and benefits	279.1	320.2
Deferred tax liabilities	558.4	557.0
Other non-current liabilities	480.7	456.4
Liabilities of Disposal Group, Including Discontinued Operation, Noncurrent	11.9	33.9
Total liabilities	5,959.5	5,525.6
Equity
Shareholders' equity attributable to Pentair plc and subsidiaries	4,967.4	6,095.3
Noncontrolling interest	0	122.4
Total equity	4,967.4	6,217.7	6,201.4	6,487.5
Total liabilities and equity	10,926.9	11,743.3
Parent Company Guarantor
Current assets
Cash and cash equivalents	0	0.5
Accounts and notes receivable, net	0	2.9
Inventories		0
Other current assets	0.1	1.4
Total current assets	0.1	4.8
Property, plant and equipment, net		0
Other assets
Investments in subsidiaries	5,589.5	6,224.7
Other non-current assets	31.6	31.6
Total other assets	5,621.1	6,256.3
Total assets	5,621.2	6,261.1
Current liabilities
Current maturities of long-term debt and short-term borrowings		0
Accounts payable	0	48.1
Employee compensation and benefits	0	0.5
Other current liabilities	173.4	99.6
Total current liabilities	173.4	148.2
Other liabilities
Long-term debt	462.8
Other non-current liabilities	17.6	17.6
Total liabilities	653.8	165.8
Equity
Shareholders' equity attributable to Pentair plc and subsidiaries	4,967.4	6,095.3
Total equity		6,095.3
Total liabilities and equity	5,621.2	6,261.1
Guarantor Subsidiary [Member]
Current assets
Cash and cash equivalents	0
Accounts and notes receivable, net	0
Other current assets	16.3
Total current assets	16.3
Other assets
Investments in subsidiaries	5,751.6
Other non-current assets	0
Total other assets	5,751.6
Total assets	5,767.9
Current liabilities
Accounts payable	0
Employee compensation and benefits	0.7
Other current liabilities	4.5
Total current liabilities	5.2
Other liabilities
Long-term debt	173.2
Other non-current liabilities	0
Total liabilities	178.4
Equity
Shareholders' equity attributable to Pentair plc and subsidiaries	5,589.5
Total liabilities and equity	5,767.9
Subsidiary Issuer
Current assets
Cash and cash equivalents	0.2	47.0
Accounts and notes receivable, net	0	4.0
Inventories		0
Other current assets	8.0	0.6
Total current assets	8.2	51.6
Property, plant and equipment, net		0
Other assets
Investments in subsidiaries	7,830.7	8,066.6
Other non-current assets	1,979.7	1,302.7
Total other assets	9,810.4	9,369.3
Total assets	9,818.6	9,420.9
Current liabilities
Current maturities of long-term debt and short-term borrowings		0
Accounts payable	0	8.6
Other current liabilities	14.2	11.7
Total current liabilities	14.2	20.3
Other liabilities
Long-term debt	2,818.6	2,401.9
Deferred tax liabilities	2.2	2.2
Total liabilities	2,835.0	2,424.4
Equity
Shareholders' equity attributable to Pentair plc and subsidiaries	6,983.6	6,996.5
Total equity		6,996.5
Total liabilities and equity	9,818.6	9,420.9
Non-Guarantor Subsidiaries
Current assets
Cash and cash equivalents	156.4	208.5	219.0	237.4
Accounts and notes receivable, net	1,180.9	1,341.7
Inventories	1,199.4	1,195.1
Other current assets	402.5	359.6
Assets of Disposal Group, Including Discontinued Operation, Current	129.2	134.4
Total current assets	3,068.4	3,239.3
Property, plant and equipment, net	990.8	1,044.3
Other assets
Goodwill	4,792.6	4,860.7
Intangibles, net	1,648.6	1,749.9
Other non-current assets	370.6	352.4
Assets of Disposal Group, Including Discontinued Operation, Noncurrent	36.2	466.3
Total other assets	6,848.0	7,429.3
Total assets	10,907.2	11,712.9
Current liabilities
Current maturities of long-term debt and short-term borrowings	2.5	2.5
Accounts payable	527.2	583.8
Employee compensation and benefits	286.7	311.9
Other current liabilities	639.6	534.6
Liabilities of Disposal Group, Including Discontinued Operation, Current	60.5	72.5
Total current liabilities	1,516.5	1,505.3
Other liabilities
Long-term debt	1,481.7	1,442.7
Pension and other post-retirement compensation and benefits	279.1	320.2
Deferred tax liabilities	556.2	554.8
Other non-current liabilities	463.1	438.8
Liabilities of Disposal Group, Including Discontinued Operation, Noncurrent	11.9	33.9
Total liabilities	4,308.5	4,295.7
Equity
Shareholders' equity attributable to Pentair plc and subsidiaries	6,598.7	7,294.8
Noncontrolling interest		122.4
Total equity		7,417.2
Total liabilities and equity	10,907.2	11,712.9
Eliminations
Current assets
Accounts and notes receivable, net	0	(63.6)
Other current assets	(40.6)	0
Total current assets	(40.6)	(63.6)
Other assets
Investments in subsidiaries	(19,171.8)	(14,291.3)
Other non-current assets	(1,975.6)	(1,296.7)
Total other assets	(21,147.4)	(15,588.0)
Total assets	(21,188.0)	(15,651.6)
Current liabilities
Accounts payable	0	(63.6)
Other current liabilities	(40.6)	0
Total current liabilities	(40.6)	(63.6)
Other liabilities
Long-term debt	(1,975.6)	(1,296.7)
Other non-current liabilities	0	0
Total liabilities	(2,016.2)	(1,360.3)
Equity
Shareholders' equity attributable to Pentair plc and subsidiaries	(19,171.8)	(14,291.3)
Total equity		(14,291.3)
Total liabilities and equity	$ (21,188.0)	$ (15,651.6)