Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Excess tax expense (benefits)	$ (3,519)	$ (4,495)	$ (4,853)	$ (4,038)	$ (4,100)
Discrete tax benefit relating to stock-based compensation	3,300		4,000
Discrete tax benefit relating to the Tax Act		$ 4,400		$ 4,400
Discrete tax benefit relating to the repatriation of foreign earnings			500
Unrecognized tax benefits decrease as a result of the expiration of certain statutes			400
Valuation allowance against certain deferred tax assets	$ 32,300		$ 32,300
Federal corporate income tax rate			21.00%	35.00%
Non-Recurring income tax benefit					3,700
Expected tax refund					$ 700
Percentage of net operating losses can be carried forward indefinitely	80.00%		80.00%