2.2.0.25falsefalse40404 - Disclosure - Note 4. Share-Based Compensation (Schedule of Share-Based Compensation Expense) (Details)truefalseIn Millionsfalse1falsefalseUSDfalsefalse2/1/2010 - 1/31/2011
USD ($)
USD ($) / shares
$Duration_2_1_2010_To_1_31_2011http://www.sec.gov/CIK0000104169duration2010-02-01T00:00:002011-01-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit15Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit16Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDfalsefalse2/1/2009 - 1/31/2010
USD ($)
USD ($) / shares
$Duration_2_1_2009_To_1_31_2010http://www.sec.gov/CIK0000104169duration2009-02-01T00:00:002010-01-31T00:00:00Unit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170Unit16Dividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0Unit15Standardhttp://www.xbrl.org/2003/instancepurexbrli0Unit1Standardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$3falsefalseUSDfalsefalse2/1/2008 - 1/31/2009
USD ($)
USD ($) / shares
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-Name Statement of Financial Accounting Standard (FAS)
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-Name Statement of Financial Accounting Standard (FAS)
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-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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