Discontinued Operations (Detail)	3 Months Ended
Mar. 31, 2019 property
Discontinued Operations and Disposal Groups [Abstract]
Number of Properties Classified As Discontinued Operations	0

The number of properties classified as discontinued operations.

No definition available.

Name:	adc_NumberOfPropertiesClassifiedAsDiscontinuedOperations
Namespace Prefix:	adc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration