Condensed Consolidating Balance Sheet (Detail) (USD $) In Millions, unless otherwise specified	Mar. 30, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Current assets
Cash and cash equivalents	$ 215	$ 261	$ 55	$ 50
Accounts and notes receivable, net	1,404	1,295
Inventories	1,327	1,379
Other current assets	344	324
Total current assets	3,290	3,259
Property, plant and equipment, net	1,222	1,224
Other assets
Goodwill	4,867	4,895
Intangibles, net	1,859	1,910
Other non-current assets	483	487
Total other assets	7,209	7,292
Total assets	11,721	11,775
Current liabilities
Current maturities of long-term debt and short-term borrowings	6	3
Accounts payable	580	570
Employee compensation and benefits	264	294
Other current liabilities	633	672
Total current liabilities	1,483	1,539
Other liabilities
Long-term debt	2,592	2,454
Pension and other post-retirement compensation and benefits	370	378
Deferred tax liabilities	481	488
Other non-current liabilities	452	437
Total liabilities	5,378	5,296
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	6,228	6,363
Noncontrolling interest	115	116
Total equity	6,343	6,479	2,144	2,047
Total liabilities and equity	11,721	11,775
Parent Company Guarantor
Current assets
Accounts and notes receivable, net	18	20
Other current assets	1	2
Total current assets	19	22
Other assets
Investments in subsidiaries	6,356	6,492
Other non-current assets	31	31
Total other assets	6,387	6,523
Total assets	6,406	6,545
Current liabilities
Accounts payable	99	54
Other current liabilities	48	97
Total current liabilities	147	151
Other liabilities
Other non-current liabilities	31	31
Total liabilities	178	182
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	6,228	6,363
Total equity	6,228	6,363
Total liabilities and equity	6,406	6,545
Subsidiary Issuer
Current assets
Accounts and notes receivable, net	10	1,459
Total current assets	10	1,459
Other assets
Investments in subsidiaries	7,469	7,470
Other non-current assets	1,551	6
Total other assets	9,020	7,476
Total assets	9,030	8,935
Current liabilities
Accounts payable	4	2
Other current liabilities	14	11
Total current liabilities	18	13
Other liabilities
Long-term debt	2,400	2,298
Total liabilities	2,418	2,311
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	6,612	6,624
Total equity	6,612	6,624
Total liabilities and equity	9,030	8,935
Non-Guarantor Subsidiaries
Current assets
Cash and cash equivalents	215	261
Accounts and notes receivable, net	1,507	1,351
Inventories	1,327	1,379
Other current assets	343	322
Total current assets	3,392	3,313
Property, plant and equipment, net	1,222	1,224
Other assets
Goodwill	4,867	4,895
Intangibles, net	1,859	1,910
Other non-current assets	475	481
Total other assets	7,201	7,286
Total assets	11,815	11,823
Current liabilities
Current maturities of long-term debt and short-term borrowings	6	3
Accounts payable	598	590
Employee compensation and benefits	264	294
Other current liabilities	571	564
Total current liabilities	1,439	1,451
Other liabilities
Long-term debt	1,745	1,615
Pension and other post-retirement compensation and benefits	370	378
Deferred tax liabilities	481	488
Other non-current liabilities	452	437
Total liabilities	4,487	4,369
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	7,213	7,338
Noncontrolling interest	115	116
Total equity	7,328	7,454
Total liabilities and equity	11,815	11,823
Eliminations
Current assets
Accounts and notes receivable, net	(131)	(1,535)
Total current assets	(131)	(1,535)
Other assets
Investments in subsidiaries	(13,825)	(13,962)
Other non-current assets	(1,574)	(31)
Total other assets	(15,399)	(13,993)
Total assets	(15,530)	(15,528)
Current liabilities
Accounts payable	(121)	(76)
Total current liabilities	(121)	(76)
Other liabilities
Long-term debt	(1,553)	(1,459)
Other non-current liabilities	(31)	(31)
Total liabilities	(1,705)	(1,566)
Equity
Shareholders' equity attributable to Pentair Ltd. and subsidiaries	(13,825)	(13,962)
Total equity	(13,825)	(13,962)
Total liabilities and equity	$ (15,530)	$ (15,528)