Shareholders' Equity Shareholder's Equity Dividends (Details) (USD $)	0 Months Ended	3 Months Ended	9 Months Ended
Aug. 01, 2012	May 02, 2012	Feb. 29, 2012	Aug. 03, 2011	May 04, 2011	Mar. 03, 2011	Sep. 28, 2012	Sep. 30, 2011	Sep. 28, 2012	Sep. 30, 2011
Dividends Payable [Line Items]
Dividends Payable, Date Declared, Day, Month and Year	Aug. 01, 2012	May 02, 2012	Feb. 29, 2012	Aug. 03, 2011	May 04, 2011	Mar. 03, 2011
Dividends declared per ordinary share	$ 0.10	$ 0.10	$ 0.10	$ 0.10	$ 0.05	$ 0.05	$ 0.10	$ 0.10	$ 0.30	$ 0.20

The day, month and year (YYYY-MM-DD) that the dividend to be paid was declared.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration