CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited) shares in Thousands, $ in Thousands	6 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) shares
Operating activities:
Net (loss) income	$ (13,410)	$ 3,821
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	16,547	6,920
Amortization of debt issuance costs and debt discount	3,048	2,884
Amortization of deferred financing costs	552
Provision for doubtful accounts	166	(73)
Non-cash stock compensation	4,514	3,718
Deferred income taxes	4,827	632
Environmental charge	902	170
Earnings on equity investment in joint venture	(1,086)	(1,044)
Changes in assets and liabilities:
Trade accounts receivable	19,938	21,400
Other receivables	(3,145)	1,472
Inventory	(9,956)	(8,986)
Prepaid expenses and other current assets	(472)	(488)
Other assets	(953)	182
Accounts payable	16,221	(2,312)
Accrued expenses and other liabilities	9,212	(8,089)
Net cash provided by operating activities	46,905	20,207
Investing activities:
Payment for net assets of business acquired		(270,000)
Purchases of investments	(2,683)	(1,037)
Sales of investments	1,694
Payments for intangible assets	(692)	(2,872)
Purchases of property and equipment, net	(3,041)	(656)
Net cash used in investing activities	(4,722)	(274,565)
Financing activities:
Payment of cash dividends	(3,929)	(3,961)
Proceeds from exercise of stock options	595	510
Excess tax benefit on stock option exercises and restricted stock		569
Borrowings of bank loans		265,000
Payment for deferred financing costs		(5,407)
Repayment of bank loans	(30,582)	(98)
Net cash (used in) provided by financing activities	(33,916)	256,613
Effect of exchange rate changes on cash	983	(1,075)
Net increase in cash	9,250	1,180
Cash and cash equivalents at beginning of period	55,680	66,828
Cash and cash equivalents at end of period	$ 64,930	$ 68,008
Noncash Investing and Financing Items [Abstract]
Number of shares to be issued | shares		5,122
Fair value of future issuance of shares		$ 90,400