Discontinued operations - Discontinued operations results of operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Revenue	$ 8,823	$ 8,302
Cost of operations	2,223	5,957
Interest expense	(481)	(445)
Provision for income taxes	4,879	722
Income from discontinued operations	0	1,663
Patriot Transportation
Revenue	0	31,717
Cost of operations	0	28,965
Operating profit	0	2,752
Interest expense	0	(26)
Income before income taxes	0	2,726
Provision for income taxes	0	1,063
Income from discontinued operations	$ 0	$ 1,663