Acquired Lease Intangibles (Narrative) (Details)	9 Months Ended
Sep. 30, 2012
Minimum [Member]
Acquired Lease Intangibles [Line Items]
Amortization period of acquired lease intangible assets	1 month
Maximum [Member]
Acquired Lease Intangibles [Line Items]
Amortization period of acquired lease intangible assets	25 years

Acquired lease intangible assets, amortization period

No definition available.

Name:	reit_AcquiredLeaseIntangibleAssetsAmortizationPeriod
Namespace Prefix:	reit_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration