Summary of Significant Accounting Policies - Earnings per Share (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share Basic And Diluted [Line Items]
Net income attributable to Agree Realty Corporation	$ 21,229	$ 18,347
Less: Income attributable to unvested restricted shares	(81)	(96)
Net income used in basic and diluted earnings per share	$ 21,148	$ 18,251
Weighted average number of common shares outstanding	45,615,400	37,688,915
Less: Unvested restricted stock	(179,209)	(201,064)
Weighted average number of common shares outstanding used in basic earnings per share	45,436,191	37,487,851
Weighted average number of common shares outstanding used in basic earnings per share	45,436,191	37,487,851
Effect of dilutive securities: Share-based compensation	69,069	65,781
Weighted average number of common shares outstanding used in diluted earnings per share	45,565,054	38,320,307
Restricted Stock [Member]
Earnings Per Share Basic And Diluted [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,719
September 2018 Forward Sales
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering		766,675
2019 ATM Forward Equity
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering	57,158
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	57,163
2020 ATM Forward Equity
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering	2,636	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	29,418

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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