Annual report pursuant to Section 13 and 15(d)

Income taxes - Schedule of Components of Income From Continuing Operations before Income Taxes (Details)

v3.10.0.1
Income taxes - Schedule of Components of Income From Continuing Operations before Income Taxes (Details) - USD ($)
$ in Thousands
12 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2016
Income before income taxes:      
United States $ 248,360 $ 257,910 $ 238,871
Foreign 50,849 56,325 47,097
Income before income taxes $ 299,209 $ 314,235 $ 285,968