Debt Obligations (Details) (USD $)	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012	Sep. 30, 2012
Debt Obligations
Total debt obligations	$ 258,155,000		$ 258,155,000		$ 206,684,000
Junior subordinated notes
Debt Obligations
Total debt obligations	37,400,000		37,400,000		37,400,000
Other disclosures
Interest expense	458,000	281,000	916,000	561,000
Amortization of deferred costs included in interest expense	5,000	5,000	10,000	10,000
Junior subordinated notes | March 15, 2011 through July 31, 2012
Debt Obligations
Interest Rate (as a percent)	3.00%		3.00%
Junior subordinated notes | August 1, 2012 through April 29, 2016
Debt Obligations
Interest Rate (as a percent)	4.90%		4.90%
Junior subordinated notes | April 30, 2016 through April 30, 2036
Debt Obligations
Reference rate			LIBOR
Margin interest above reference rate (as a percent)	2.00%		2.00%
Mortgages payable
Debt Obligations
Total debt obligations	220,755,000		220,755,000		169,284,000
Wholly-owned subsidiary | Line of credit
Debt Obligations
Reference rate	LIBOR
Margin interest above reference rate (as a percent)	4.00%		4.00%
Other disclosures
Amortization of deferred costs included in interest expense	38,000	37,000	75,000	74,000
Outstanding balances on facility	0		0		0
Wholly-owned subsidiary | Line of credit | Minimum
Debt Obligations
Interest Rate (as a percent)	5.50%		5.50%
Wholly-owned subsidiary | Line of credit | Secured borrowings
Debt Obligations
Maximum amount that may be borrowed under the facility	25,000,000		25,000,000
Wholly-owned subsidiary | Line of credit | Unsecured borrowings
Debt Obligations
Maximum amount that may be borrowed under the facility	$ 10,000,000		$ 10,000,000
Wholly-owned subsidiary | Line of credit | Unsecured borrowings | Maximum
Debt Obligations
Borrowing period			90 days