Real Estate and Intangibles - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($) Property	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) Property	Jun. 30, 2020 USD ($)
Real Estate Properties [Line Items]
Revenues	$ 68,614	$ 60,526	$ 133,615	$ 118,744
Net income available to Easterly Government Properties, Inc.	8,201	3,666	15,192	5,363
Acquisition-related expenses	483	$ 668	970	$ 1,206
Net proceeds from the sale of operating property			3,326
Gain on the sale of operating property	$ 530		530
Operating Properties Acquired [Member]
Real Estate Properties [Line Items]
Acquisition-related expenses			1,000
Net proceeds from the sale of operating property			3,300
Gain on the sale of operating property			$ 500
Operating Properties Acquired [Member] | FBI Knoxville ICE Louisville, USAO Louisville, USAO Springfield and NWS Kansas City [Member]
Real Estate Properties [Line Items]
Number of properties | Property	5		5
Purchase price	$ 111,400		$ 111,400
Operating Properties Acquired [Member] | D H A Aurora F B I D E A El Paso V A Mobile And V A Chico And F B I Member
Real Estate Properties [Line Items]
Weighted average amortization period			10 years 8 months 8 days
Revenues			$ 2,400
Net income available to Easterly Government Properties, Inc.			$ 500