Summary of Significant Accounting Policies - Earnings per Share (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share Basic And Diluted [Line Items]
Net income attributable to Agree Realty Corporation	$ 18,347	$ 16,451
Less: Income attributable to unvested restricted shares	(96)	(112)
Net income used in basic and diluted earnings per share	$ 18,251	$ 16,339
Weighted average number of common shares outstanding	37,688,915	31,013,545
Less: Unvested restricted stock	(201,064)	(212,074)
Weighted average number of common shares outstanding used in basic earnings per share	37,487,851	30,801,471
Weighted average number of common shares outstanding used in basic earnings per share	37,487,851	30,801,471
Effect of dilutive securities: restricted stock	65,781	49,587
Weighted average number of common shares outstanding used in diluted earnings per share	38,320,307	30,851,058
September 2018 Forward Sales [Member]
Earnings Per Share Basic And Diluted [Line Items]
Effect of dilutive securities: forward equity offering	766,675	0

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

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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