Business Segments - Business segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013	Nov. 07, 2013	Sep. 30, 2013	Sep. 30, 2012
Revenues	$ 39,907	$ 33,868	$ 78,727	$ 66,925
Operating profit	3,146	4,308	7,270	8,716
Interest expense	346	580	657	1,008
Capital expenditures (a)	1,439	1,981	13,939	12,932
Depreciation, depletion and amortization	4,168	3,467	7,943	6,738
Cash items	1,132	4,527	1,132	4,527		502	6,713
Total identifiable net assets	299,905		299,905			287,093
(a) Capital expenditures related to the Pipeline Transportation, Inc. acquisition					3,397
Transportation
Revenues	31,900	27,176	63,491	53,815
Operating profit	1,324	2,328	3,272	4,596
Corporate expenses	(427)	(407)	(919)	(878)
Capital expenditures (a)	410	574	9,141	7,361
Depreciation, depletion and amortization	2,294	1,827	4,324	3,580
Identifiable net assets	60,985		60,985			49,410
(a) Capital expenditures related to the Pipeline Transportation, Inc. acquisition	3,397		3,397
Mining royalty land
Revenues	1,226	1,244	2,494	2,575
Operating profit	1,068	1,102	2,196	2,301
Corporate expenses	(189)	(176)	(378)	(352)
Interest expense	39	12	65	23
Capital expenditures (a)	0	0	0	0
Depreciation, depletion and amortization	28	23	56	48
Identifiable net assets	39,214		39,214			40,008
Developed property rentals
Revenues	6,781	5,448	12,742	10,535
Operating profit	2,477	2,394	4,843	4,509
Corporate expenses	(283)	(264)	(566)	(528)
Interest expense	307	568	592	985
Capital expenditures (a)	436	626	3,570	3,838
Capital expenditures - Capitalized interest	477	417	993	1,008
Capital expenditures - Internal labor	100	108	195	218
Capital expenditures - Real estate taxes	16	256	40	507
Depreciation, depletion and amortization	1,723	1,515	3,322	2,903
Identifiable net assets	195,393		195,393			195,476
Corporate
Corporate expenses	(824)	(669)	(1,178)	(932)
Depreciation, depletion and amortization	123	102	241	207
Identifiable net assets	$ 3,181		$ 3,181			$ 1,697