Supplemental Cash Flow Information (Details) (USD $)	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Supplemental Cash Flow Information (Textual)
Cash paid for interest	$ 8,623,791us-gaap_InterestPaid	$ 8,071,712us-gaap_InterestPaid
Amount of dividend reinvested	$ 4,131,530mnr_AmountOfDividendReinvested	$ 3,670,902mnr_AmountOfDividendReinvested

The amount of cash paid for interest during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

Name:	us-gaap_InterestPaid
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration