Fair Value of Financial Instruments - Additional Information (Details)	9 Months Ended
Sep. 30, 2022 dealer
Fair Value Disclosures [Abstract]
Number of dealers received quotes from, trading	3

Trading Securities, Quotes Received, Number of Dealers

No definition available.

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Namespace Prefix:	arr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration