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DESCRIPTION OF BUSINESS (Tables) | 12 Months Ended
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Dec. 31, 2020
Accounting Policies [Abstract] |
Schedule of Investment Groups | The Company’s four investment groups are primarily comprised of the following:
Investment Groups | Description
Annaly Agency Group | Invests in Agency mortgage-backed securities (“MBS”) collateralized by residential mortgages which are guaranteed by Fannie Mae, Freddie Mac or Ginnie Mae.
Annaly Residential Credit Group | Invests primarily in non-Agency residential mortgage assets within securitized product and whole loan markets.
Annaly Commercial Real Estate Group | Originates and invests in commercial mortgage loans, securities, and other commercial real estate debt and equity investments.
Annaly Middle Market Lending Group | Provides financing to private equity-backed middle market businesses, focusing primarily on senior debt within select industries.

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