XML 30 R62.htm IDEA: XBRL DOCUMENT v2.4.1.9
Fair Value Disclosures - Quantitative Information (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 12 Months Ended
Mar. 31, 2015
Dec. 31, 2014
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Derivative Liability 46,623us-gaap_DerivativeLiabilities 38,217us-gaap_DerivativeLiabilities
Fair Value, Measurements, Recurring [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Marketable Securities 1,832,437us-gaap_MarketableSecurities
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Prepayment Rate 10.00%us-gaap_FairValueInputsPrepaymentRate
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Range of Offered Quotes 82.00%agm_FairValueInputsRangeOfOfferedQuotes
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Discount Rate 12.20%us-gaap_FairValueInputsDiscountRate
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Discount Rate 0.80%us-gaap_FairValueInputsDiscountRate
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Discount Rate 0.80%us-gaap_FairValueInputsDiscountRate
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Discount Rate 1.10%us-gaap_FairValueInputsDiscountRate
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Range of Offered Quotes 92.00%agm_FairValueInputsRangeOfOfferedQuotes
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Discount Rate 20.90%us-gaap_FairValueInputsDiscountRate
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Range of Offered Quotes 87.70%agm_FairValueInputsRangeOfOfferedQuotes
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Weighted Average [Member] | Cost Approach Valuation Technique [Member] | Asset-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Fair Value Inputs, Discount Rate 1.80%us-gaap_FairValueInputsDiscountRate
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Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
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