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USD ($)
USD ($) / shares
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USD ($)
USD ($) / shares
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19
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1/1/2010 - 12/31/2010
USD ($)
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1/1/2009 - 12/31/2009
USD ($)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19
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1/1/2010 - 12/31/2010
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Mortgage Backed Securities
1/1/2009 - 12/31/2009
USD ($)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Mortgage Backed Securities
1/1/2010 - 12/31/2010
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Mortgage Backed Securities
1/1/2009 - 12/31/2009
USD ($)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19
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1/1/2010 - 12/31/2010
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Mortgage Backed Securities
1/1/2009 - 12/31/2009
USD ($)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19
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1/1/2010 - 12/31/2010
USD ($)
$Duration_1_1_2010_To_12_31_2010232http://www.sec.gov/CIK0000731766duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseNon-investment Gradeus-gaap_CreditDerivativesByPaymentAndPerformanceRiskCreditRatingAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ExternalCreditRatingNonInvestmentGradeMemberus-gaap_CreditDerivativesByPaymentAndPerformanceRiskCreditRatingAxisexplicitMemberUnit12Standardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$12falsefalseUSDtruefalse{us-gaap_CreditDerivativesByPaymentAndPerformanceRiskCreditRatingAxis} : Non-investment Grade
1/1/2009 - 12/31/2009
USD ($)
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19
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