QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Details) - Schedule of quarterly financial information - 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
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 574,164	$ 574,970	$ 549,633	$ 510,522	$ 545,505	$ 516,550	$ 478,560	$ 437,303	$ 2,209,289	$ 1,977,918	$ 1,524,997
Gross Profit	160,236	154,483	137,504	143,046	148,341	138,682	121,379	120,779	595,269	529,181	408,126
Income from continuing operations	$ 16,251	$ 14,128	$ 6,490	$ 8,753	$ 1,031	$ 7,442	$ 1,951	$ 22,831	$ 45,622	$ 33,255	$ 17,783
Per Share - Basic (in usd per share)	$ 0.40	$ 0.34	$ 0.16	$ 0.21	$ 0.03	$ 0.18	$ 0.05	$ 0.54	$ 1.11	$ 0.81	$ 0.43
Per Share - Diluted (in usd per share)	$ 0.37	$ 0.33	$ 0.15	$ 0.21	$ 0.02	$ 0.18	$ 0.05	$ 0.53	$ 1.06	$ 0.78	$ 0.41