Shareholders Equity - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended
Jun. 18, 2012	Feb. 17, 2012	Dec. 09, 2011	May 15, 2008	Jun. 30, 2012
Equity Note
Share repurchase, authorized			$ 20.0	$ 20.0
Dividend paid, per outstanding common share	$ 0.08	$ 0.08			$ 0.08
Dividend paid, total amount					$ 2.3

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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=6959260&loc=d3e187085-122770

+ Details

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- Definition

Equity impact of common stock cash dividends declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

+ References

+ Details

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- Definition

The amount authorized by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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