Summary of Significant Accounting Policies - Acquisitions (Details)	12 Months Ended
Dec. 31, 2018 form
Accounting Policies [Abstract]
Number of forms of in-place operating lease intangible assets and liabilities	3

Represents the number of forms that can be taken by the identifiable intangible assets and liabilities relating to in-place operating leases acquired.

No definition available.

Name:	mac_NumberOfFormsOfInPlaceOperatingLeases
Namespace Prefix:	mac_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration