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USD ($)

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 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph 64
 -Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph A240
 -Subparagraph g(1)

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Staff Accounting Bulletin (SAB)
 -Number Topic 14
 -Section F

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 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph A240
 -Subparagraph h

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1/1/2011 - 3/31/2011
USD ($)
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 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph 64
 -Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph A240
 -Subparagraph g(1)

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Staff Accounting Bulletin (SAB)
 -Number Topic 14
 -Section F

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 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph A240
 -Subparagraph h

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 -Number 123R
 -Paragraph A240
 -Subparagraph h

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USD ($)

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1/1/2010 - 3/31/2010
USD ($)
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 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph 64
 -Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph A240
 -Subparagraph g(1)

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Staff Accounting Bulletin (SAB)
 -Number Topic 14
 -Section F

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 -Number 123R
 -Paragraph A240
 -Subparagraph h

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 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
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