Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Jan. 01, 2019
Accounting Policies [Line Items]
Limited Partners' Capital Account, Units Outstanding	47,349,728
Amortization of above and below Market Leases	$ 3,809,000	$ 3,276,000
Number Of Real Estate Properties Held-For-Sale	5
Escrow Deposit	$ 20,049,000		$ 26,554,000
Cash in Excess of FDIC Insured Amounts	91,100,000		40,900,000
Straight-line rent receivables	$ 24,300,000		23,000,000.0
Number of Reportable Segments	1
Right of use assets	$ 15,900,000
Lease liabilities	16,110,000
ASU 2016-02 | Restatement
Accounting Policies [Line Items]
Right of use assets				$ 7,500,000
Lease liabilities				$ 7,500,000
Unbilled Revenues
Accounting Policies [Line Items]
Accounts Receivable, Gross	$ 2,000,000.0		$ 2,600,000
Building [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Building Improvements [Member] | Minimum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Building Improvements [Member] | Maximum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	20 years
Agree Realty Corporation [Member] | General Partner
Accounting Policies [Line Items]
Percentage of Operating Partnership Owned	99.30%		99.20%
Agree Realty Corporation [Member] | Third party
Accounting Policies [Line Items]
Non controlling interest	0.70%		0.80%