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Period Type:	duration

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

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Period Type:	duration

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: 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

+ Details

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Share capital - Summary of Dividends Paid Per Share (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012
Class of Stock [Line Items]
Dividends per share	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.44	$ 0.44
First Quarter Dividend Payment [Member]
Class of Stock [Line Items]
Dividends per share									$ 0.11
Record Date									Feb. 08, 2013
Payment Date									Feb. 22, 2013
Second Quarter Dividend Payment [Member]
Class of Stock [Line Items]
Dividends per share									$ 0.11
Record Date									May 10, 2013
Payment Date									May 24, 2013
Third Quarter Dividend Payment [Member]
Class of Stock [Line Items]
Dividends per share									$ 0.11
Record Date									Aug. 09, 2013
Payment Date									Aug. 23, 2013
Fourth Quarter Dividend Payment [Member]
Class of Stock [Line Items]
Dividends per share									$ 0.11
Record Date									Nov. 08, 2013
Payment Date									Nov. 22, 2013