Quarterly Results (Unaudited) (Details) - USD ($) $ / shares in Units, $ 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
Unaudited quarterly consolidated statement of operations
Revenue	$ 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
Loss before provision for income taxes	(5,163)	(4,107)	(4,034)	(4,756)	(6,547)	(3,093)	(5,276)	(6,027)	(18,060)	(20,943)	(39,638)
Net loss	$ (5,227)	$ (4,649)	$ (4,362)	$ (5,022)	$ (1,043)	$ (3,705)	$ (5,655)	$ (1,212)	$ (19,260)	$ (11,615)	$ (39,187)
Unaudited quarterly consolidated statement of operations
Basic and diluted loss per common share (USD per share)	$ (0.16)	$ (0.14)	$ (0.13)	$ (0.15)	$ (0.03)	$ (0.12)	$ (0.18)	$ (0.04)	$ (0.58)	$ (0.36)	$ (1.25)
Basic and diluted weighted average shares outstanding (in shares)	33,291,275	33,164,750	32,987,608	32,808,144	32,425,669	32,104,368	31,972,752	31,876,603	33,062,976	32,095,491	31,402,921

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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