Income Taxes - Components of Income Before Income Taxes and Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Income before income taxes:
United States									$ 57,281	$ 43,368	$ 30,499
Foreign									2,246	(795)	569
Income before income taxes	$ 12,587	$ 19,466	$ 16,866	$ 10,608	$ 16,628	$ 5,905	$ 10,468	$ 9,572	59,527	42,573	31,068
Federal:
Current									11,454	4,470	11,476
Deferred									(3,008)	(4,527)	(7,645)
Federal Income Tax Expense (Benefit), Continuing Operations, Total									8,446	(57)	3,831
State:
Current									5,194	2,370	3,650
Deferred									(1,421)	(537)	(1,684)
State and Local Income Tax Expense (Benefit), Continuing Operations, Total									3,773	1,833	1,966
Foreign:
Current									546	186	240
Deferred									(13)	(272)	156
Foreign, Income Tax expense benefit									533	(86)	396
Income tax expense (benefit)	$ (217)	$ 5,357	$ 4,483	$ 3,129	$ 6,527	$ 2,209	$ 1,335	$ (8,381)	$ 12,752	$ 1,690	$ 6,193