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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Segment Information - Schedule of Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Total revenue from operations	$ 58,790	$ 56,882	$ 56,800	$ 54,053	$ 52,705	$ 50,569	$ 60,097	$ 61,143	$ 226,525	$ 224,514	$ 270,015
Gross profit	$ 29,038	$ 28,551	$ 29,218	$ 26,473	$ 24,857	$ 27,144	$ 27,511	$ 30,200	113,280	109,712	124,490
Operating Segments \| GovDeals
Segment Reporting Information [Line Items]
Total revenue from operations									32,936	30,214	26,853
Gross profit									30,386	27,990	25,172
Operating Segments \| CAG
Segment Reporting Information [Line Items]
Total revenue from operations									60,242	88,025	145,131
Gross profit									32,679	48,873	71,934
Operating Segments \| RSCG
Segment Reporting Information [Line Items]
Total revenue from operations									127,321	101,954	95,032
Gross profit									44,967	33,009	30,050
Operating Segments \| Machinio
Segment Reporting Information [Line Items]
Total revenue from operations									5,598	653	0
Gross profit									5,196	501	0
Corporate & Other
Segment Reporting Information [Line Items]
Total revenue from operations									428	3,668	2,999
Gross profit									52	(661)	(2,666)
Revenue
Segment Reporting Information [Line Items]
Total revenue from operations									147,889	149,677	188,570
Revenue \| Operating Segments \| GovDeals
Segment Reporting Information [Line Items]
Total revenue from operations									0	0	0
Revenue \| Operating Segments \| CAG
Segment Reporting Information [Line Items]
Total revenue from operations									36,684	57,717	100,160
Revenue \| Operating Segments \| RSCG
Segment Reporting Information [Line Items]
Total revenue from operations									110,736	88,295	85,766
Revenue \| Operating Segments \| Machinio
Segment Reporting Information [Line Items]
Total revenue from operations									0	0	0
Revenue \| Corporate & Other
Segment Reporting Information [Line Items]
Total revenue from operations									469	3,665	2,644
Fee revenue
Segment Reporting Information [Line Items]
Total revenue from operations									78,636	74,837	81,445
Fee revenue \| Operating Segments \| GovDeals
Segment Reporting Information [Line Items]
Total revenue from operations									32,936	30,214	26,853
Fee revenue \| Operating Segments \| CAG
Segment Reporting Information [Line Items]
Total revenue from operations									23,558	30,308	44,971
Fee revenue \| Operating Segments \| RSCG
Segment Reporting Information [Line Items]
Total revenue from operations									16,585	13,659	9,265
Fee revenue \| Operating Segments \| Machinio
Segment Reporting Information [Line Items]
Total revenue from operations									5,598	653	0
Fee revenue \| Corporate & Other
Segment Reporting Information [Line Items]
Total revenue from operations									$ (41)	$ 3	$ 356