Summary of Significant Accounting Policies - Earnings per Share (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share Basic And Diluted [Line Items]
Net income attributable to Agree Realty Corporation	$ 25,258	$ 18,564	$ 46,486	$ 36,911
Less: Income attributable to unvested restricted shares	(83)	(89)	(164)	(185)
Net income used in basic and diluted earnings per share	$ 25,175	$ 18,475	$ 46,322	$ 36,726
Weighted average number of common shares outstanding	52,902,628	40,813,436	49,259,014	39,259,807
Less: Unvested restricted stock	(176,398)	(201,064)	(176,398)	(201,064)
Weighted average number of common shares outstanding used in basic earnings per share	52,726,230	40,612,372	49,082,616	39,058,743
Weighted average number of common shares outstanding used in basic earnings per share	52,726,230	40,612,372	49,082,616	39,058,743
Effect of dilutive securities: Share-based compensation	68,294	82,836	74,926	80,030
Weighted average number of common shares outstanding used in diluted earnings per share	53,266,740	41,141,659	49,423,546	39,745,337
Restricted Stock [Member]
Earnings Per Share Basic And Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	7,606		4,682
Performance Units [Member]
Earnings Per Share Basic And Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	7,416		5,635
September 2018 Forward Sales
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering		312,464		539,570
April 2019 Forward Equity
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering		133,987		66,994
April 2020 Forward Equity
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering	25,652		14,144
2019 ATM Forward Equity
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering			28,579
2019 ATM Forward Equity \| Forward Sale Agreement [Member]
Earnings Per Share Basic And Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	11,296		34,230
2020 ATM Forward Equity
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering	446,563	0	223,281	0
2020 ATM Forward Equity \| Forward Sale Agreement [Member]
Earnings Per Share Basic And Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	70,769		50,093

The amount net income (loss) attributable to unvested restricted stocks.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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