Changes in Accounting Principles and Corrections to Previously Issued Financial Statements - Schedules of Accounting Adjustments (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Mar. 31, 2019	Mar. 31, 2018
Income Statement Related Disclosures [Abstract]
Cost of goods sold	$ 106,779			$ 105,629			$ 312,513	$ 302,349
Gross profit	39,900			52,298			141,379	154,657
Selling expenses	34,422			37,754			111,323	112,736
General and administrative expenses	11,306			14,157			32,063	39,822
Operating Expenses	46,002			55,083			149,057	155,588
Income (loss) from operations	(6,102)			(2,785)			(7,678)	(931)
Interest Expense	(2,981)			(2,547)			(9,165)	(7,221)
Other, net	495			1,817			2,105	5,782
Nonoperating Income (Expense)	(2,486)			(729)			(18,008)	(1,425)
Income (loss) before taxes	(8,588)			(3,514)			(25,686)	(2,356)
Income tax expense (benefit)	43,161			(1,321)			39,149	16,058
Net loss	(51,749)	$ (10,100)	$ (2,986)	(2,193)	$ (17,060)	$ 840	(64,835)	(18,414)
Net loss available to common stockholders	$ (51,883)			$ (2,321)			$ (65,235)	$ (18,671)
Net income available to common stockholders per common share—basic (in US$ per share)	$ (3.05)			$ (0.14)			$ (3.84)	$ (1.12)
Net income available to common stockholders per common share—diluted (in US$ per share)	$ (3.05)			$ (0.14)			$ (3.84)	$ (1.12)
Adjustments to reconcile net loss to net cash provided by operating activities:
Deferred income taxes							$ 40,078	$ 15,698
Net losses (gains) on derivative instruments and investments							9,228	305
Change in operating assets and liabilities:
Inventories							3,937	(7,348)
Derivative assets (liabilities), net							(13,229)	(6,129)
Accounts payable							8,466	7,554
Unrealized losses on derivative instruments designated as cash flow hedges, net of tax	$ (5,905)			$ (2,430)			(11,254)	(4,255)
Gains (losses) on derivative instruments designated as cash flow hedges reclassified to cost of goods sold, net of tax	3,201			438			6,311	(426)
Total comprehensive loss, net of tax	$ (53,595)			(4,185)			$ (66,424)	(23,095)
As Previously Reported
Income Statement Related Disclosures [Abstract]
Cost of goods sold				99,117				283,670
Gross profit				58,810				173,336
Selling expenses				44,736				132,979
General and administrative expenses				13,766				39,007
Operating Expenses				61,674				175,016
Income (loss) from operations				(2,864)				(1,680)
Interest Expense				(902)				(2,286)
Other, net				154				794
Nonoperating Income (Expense)				(747)				(1,478)
Income (loss) before taxes				(3,611)				(3,158)
Income tax expense (benefit)				297				20,497
Net loss				(3,908)				(23,655)
Net loss available to common stockholders				$ (4,036)				$ (23,912)
Net income available to common stockholders per common share—basic (in US$ per share)				$ (0.24)				$ (1.43)
Net income available to common stockholders per common share—diluted (in US$ per share)				$ (0.24)				$ (1.43)
Adjustments to reconcile net loss to net cash provided by operating activities:
Deferred income taxes								$ 20,138
Net losses (gains) on derivative instruments and investments								3,292
Change in operating assets and liabilities:
Inventories								(9,533)
Derivative assets (liabilities), net								(6,091)
Accounts payable								7,516
Unrealized losses on derivative instruments designated as cash flow hedges, net of tax				$ (2,437)				(4,148)
Gains (losses) on derivative instruments designated as cash flow hedges reclassified to cost of goods sold, net of tax				1,355				1,724
Total comprehensive loss, net of tax				(4,990)				(26,079)
Restatement Adjustment
Income Statement Related Disclosures [Abstract]
Cost of goods sold				(87)				(216)
Gross profit				87				216
Selling expenses				(287)				(546)
General and administrative expenses				391				815
Operating Expenses				104				269
Income (loss) from operations				(18)				(53)
Interest Expense				(1,645)				(4,935)
Other, net				1,663				4,988
Nonoperating Income (Expense)				18				53
Income (loss) before taxes				0				0
Income tax expense (benefit)				0				0
Net loss				0				0
Net loss available to common stockholders				$ 0				$ 0
Net income available to common stockholders per common share—basic (in US$ per share)				$ 0.00				$ 0.00
Net income available to common stockholders per common share—diluted (in US$ per share)				$ 0.00				$ 0.00
Restatement Adjustment | LIFO to FIFO Adjustment
Income Statement Related Disclosures [Abstract]
Cost of goods sold				$ (891)				$ 994
Gross profit				891				(994)
Selling expenses				0				0
General and administrative expenses				0				0
Operating Expenses				0				0
Income (loss) from operations				891				(994)
Interest Expense				0				0
Other, net				0				0
Nonoperating Income (Expense)				0				0
Income (loss) before taxes				891				(994)
Income tax expense (benefit)				(1,562)				(4,931)
Net loss				2,452				3,937
Net loss available to common stockholders				$ 2,452				$ 3,937
Net income available to common stockholders per common share—basic (in US$ per share)				$ 0.14				$ 0.23
Net income available to common stockholders per common share—diluted (in US$ per share)				$ 0.14				$ 0.23
Adjustments to reconcile net loss to net cash provided by operating activities:
Deferred income taxes								$ (4,932)
Net losses (gains) on derivative instruments and investments								(2,987)
Change in operating assets and liabilities:
Inventories								3,981
Derivative assets (liabilities), net								(38)
Accounts payable								38
Restatement Adjustment | Preferable Freight and Warehousing Adjustments
Income Statement Related Disclosures [Abstract]
Cost of goods sold				$ 5,888				15,578
Gross profit				(5,888)				(15,578)
Selling expenses				(5,495)				(16,418)
General and administrative expenses				0				0
Operating Expenses				(5,495)				(16,418)
Income (loss) from operations				(393)				840
Interest Expense				0				0
Other, net				0				0
Nonoperating Income (Expense)				0				0
Income (loss) before taxes				(393)				840
Income tax expense (benefit)				436				1,699
Net loss				(829)				(859)
Net loss available to common stockholders				$ (829)				$ (859)
Net income available to common stockholders per common share—basic (in US$ per share)				$ (0.05)				$ (0.05)
Net income available to common stockholders per common share—diluted (in US$ per share)				$ (0.05)				$ (0.05)
Adjustments to reconcile net loss to net cash provided by operating activities:
Deferred income taxes								$ 1,699
Net losses (gains) on derivative instruments and investments								0
Change in operating assets and liabilities:
Inventories								(840)
Derivative assets (liabilities), net								0
Accounts payable								0
Restatement Adjustment | Corrections of Freight, Overhead Variances and PPVs
Income Statement Related Disclosures [Abstract]
Cost of goods sold				$ 1,602				2,323
Gross profit				(1,602)				(2,323)
Selling expenses				(1,200)				(3,279)
General and administrative expenses				0				0
Operating Expenses				(1,200)				(3,279)
Income (loss) from operations				(401)				956
Interest Expense				0				0
Other, net				0				0
Nonoperating Income (Expense)				0				0
Income (loss) before taxes				(401)				956
Income tax expense (benefit)				(492)				(1,207)
Net loss				92				2,163
Net loss available to common stockholders				$ 92				$ 2,163
Net income available to common stockholders per common share—basic (in US$ per share)				$ 0.01				$ 0.13
Net income available to common stockholders per common share—diluted (in US$ per share)				$ 0.01				$ 0.13
Adjustments to reconcile net loss to net cash provided by operating activities:
Deferred income taxes								$ (1,207)
Net losses (gains) on derivative instruments and investments								0
Change in operating assets and liabilities:
Inventories								(956)
Derivative assets (liabilities), net								0
Accounts payable								$ 0