Condensed Consolidated Statements of Changes in Equity (USD $) In Millions	Total	Common shares	Treasury shares	Capital contribution reserve	Retained earnings	Accumulated other comprehensive income (loss)	Total Pentair Ltd.	Noncontrolling interest
Beginning Balance at Dec. 31, 2011	$ 2,047	$ 48		$ 458	$ 1,465	$ (38)	$ 1,933	$ 114
Beginning Balance (in shares) at Dec. 31, 2011		98.6
Net income (loss)	63				62		62	1
Change in cumulative translation adjustment	40					39	39	1
Changes in market value of derivative financial instruments, net of $0 and $1 tax for the three months ended March 30, 2013 and March 31, 2012 respectively	2					2	2
Dividends declared	(22)				(22)		(22)
Exercise of options, net of shares tendered for payment (in shares)		0.3
Exercise of options, net of shares tendered for payment	10			10			10
Issuance of restricted shares, net of cancellations (in shares)		0.2
Issuance of restricted shares, net of cancellations	4			4			4
Shares surrendered by employees to pay taxes (in shares)		(0.1)
Shares surrendered by employees to pay taxes	(2)			(2)			(2)
Share-based compensation	2			2			2
Ending Balance at Mar. 31, 2012	2,144	48		472	1,505	3	2,028	116
Ending Balance (in shares) at Mar. 31, 2012		99.0
Beginning Balance at Dec. 31, 2012	6,479	113	(315)	5,285	1,292	(12)	6,363	116
Beginning Balance (in shares) at Dec. 31, 2012		213.0	(6.9)
Net income (loss)	53				52		52	1
Change in cumulative translation adjustment	(76)					(76)	(76)
Changes in market value of derivative financial instruments, net of $0 and $1 tax for the three months ended March 30, 2013 and March 31, 2012 respectively	1					1	1
Tax benefits of share-based compensation	6			6			6
Dividends declared	1			1			1
Distribution to noncontrolling interest	(2)							(2)
Share repurchase (in shares)			(2.7)
Share repurchase	(140)		(140)				(140)
Exercise of options, net of shares tendered for payment (in shares)			0.8
Exercise of options, net of shares tendered for payment	23		34	(11)			23
Issuance of restricted shares, net of cancellations (in shares)			0.5
Issuance of restricted shares, net of cancellations			24	(24)
Shares surrendered by employees to pay taxes (in shares)			(0.2)
Shares surrendered by employees to pay taxes	(12)		(9)	(3)			(12)
Share-based compensation	10			10			10
Ending Balance at Mar. 30, 2013	$ 6,343	$ 113	$ (406)	$ 5,264	$ 1,344	$ (87)	$ 6,228	$ 115
Ending Balance (in shares) at Mar. 30, 2013		213.0	(8.5)