Condensed Consolidated Statements of Changes in Shareholders' Equity (USD $) In Thousands, except Share data	Total	Common shares	Treasury shares	Capital Contribution Reserve	Retained earnings	Accumulated other comprehensive income (loss)	Total Pentair Ltd.	Non- controlling interest
Beginning Balance at Dec. 31, 2010	$ 2,205,032	$ 47,412		$ 443,478	$ 1,624,605	$ (22,342)	$ 2,093,153	$ 111,879
Beginning Balance (in shares) at Dec. 31, 2010		98,409,192
Net income	172,225				168,345		168,345	3,880
Change in cumulative translation adjustment	(29,603)					(29,263)	(29,263)	(340)
Changes in market value of derivative financial instruments, net of $2,582 in 2012 and $2,303 in 2011 tax	3,566					3,566	3,566
Cash dividends - $0.66 in 2012 and $0.60 in 2011 per common share	(59,669)				(59,669)		(59,669)
Share repurchase (in Shares)		(397,126)
Share repurchase	(12,785)	(211)		(12,574)			(12,785)
Exercise of stock options, net of 39,751 in 2012 and 181,648 in 2011 shares tendered for payment (in shares)		601,207
Exercise of stock options, net of 39,751 in 2012 and 181,648 in 2011 shares tendered for payment	13,191	320		12,871			13,191
Issuance of restricted shares, net of cancellations (in shares)		27,532
Issuance of restricted shares, net of cancellations	1,422	15		1,407			1,422
Amortization of restricted shares	743			743			743
Shares surrendered by employees to pay taxes (in Shares)		(74,782)
Shares surrendered by employees to pay taxes	(2,765)	(40)		(2,725)			(2,765)
Stock compensation	6,759			6,759			6,759
Ending Balance at Oct. 01, 2011	2,298,116	47,496		449,959	1,733,281	(48,039)	2,182,697	115,419
Ending Balance (in shares) at Oct. 01, 2011		98,566,023
Beginning Balance at Dec. 31, 2011	2,047,392	47,526		457,754	1,579,290	(151,241)	1,933,329	114,063
Beginning Balance (in shares) at Dec. 31, 2011		98,622,564
Net income	167,289				163,062		163,062	4,227
Change in cumulative translation adjustment	(3,765)					(3,661)	(3,661)	(104)
Changes in market value of derivative financial instruments, net of $2,582 in 2012 and $2,303 in 2011 tax	(5,232)					(5,232)	(5,232)
Cash dividends - $0.66 in 2012 and $0.60 in 2011 per common share	(66,153)				(66,153)		(66,153)
Issuance of shares related to the Merger (in shares)		113,611,537	(2,712,603)
Issuance of shares related to the Merger	4,904,254	65,521	(119,626)	4,958,359			4,904,254
Exercise of stock options, net of 39,751 in 2012 and 181,648 in 2011 shares tendered for payment (in shares)		669,361	3,600
Exercise of stock options, net of 39,751 in 2012 and 181,648 in 2011 shares tendered for payment	20,702	356	159	20,187			20,702
Issuance of restricted shares, net of cancellations (in shares)		168,936	2,083
Issuance of restricted shares, net of cancellations	18,985	90	92	18,803			18,985
Amortization of restricted shares	18,633			18,633			18,633
Shares surrendered by employees to pay taxes (in Shares)		(72,398)	(680)
Shares surrendered by employees to pay taxes	(2,759)	(39)	(30)	(2,690)			(2,759)
Stock compensation	9,894			9,894			9,894
Dividends declared - payable in November 2012, February 2013 and May 2013, for $0.22, $0.23 and $0.23 per common share, respectively	(142,999)			(142,999)			(142,999)
Ending Balance at Sep. 29, 2012	$ 6,966,241	$ 113,454	$ (119,405)	$ 5,337,941	$ 1,676,199	$ (160,134)	$ 6,848,055	$ 118,186
Ending Balance (in shares) at Sep. 29, 2012		213,000,000	(2,707,600)