v3.10.0.1

Financial Derivatives Financial Derivatives (Schedule of Derivative Activity) (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2018 | Dec. 31, 2017
Interest Rate Swaps [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | $ 1,113,420 | $ 1,306,853
Credit Default Swap [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | 601,794 | 531,008
Total Return Swaps [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | 36,059 | 19,760
Futures [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | 101,664 | 48,244
Options [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | 124,741 | 94,415
Forwards [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | 44,541 | 76,784
Warrant [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | 0 | 378
Mortgage Loan Purchase Commitments [Member] |  |
Derivative [Line Items] |  |
Average Monthly Notional Amount | $ 0 | $ 1,585

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- Definition Average notional for the period using absolute value of month end notional amounts. + References No definition available. + Details
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Namespace Prefix: | efc_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |