Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended												6 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, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Income Taxes
Provisional non-cash net tax charge														$ 13,100
Current Income Tax Expense (Benefit)
Federal														(9,439)	$ 764	$ 34,932
State and Local														1,152	638	1,887
Total Current Income Tax Expense (Benefit)														(8,287)	1,402	36,819
Deferred Income Tax Expense (Benefit)
Federal														31,263	(2,210)	(17,529)
State and Local														(573)	1,905	(1,968)
Total Deferred Income Tax Expense (Benefit)														30,690	(305)	(19,497)
Federal, state and local income tax (benefit)/expense	$ (883)	$ (2,275)	$ 18,138	$ 7,423	$ 3,100	$ 7,337	$ 3,542	$ (12,882)	$ (2,948)	$ (2,743)	$ 5,958	$ 17,055		$ 22,403	$ 1,097	$ 17,322
Reconciliation of the company's federal statutory tax rate to its effective rate
Federal income tax at statutory rate (as a percent)													21.00%	28.10%	35.00%	35.00%
State and local income tax, net (as a percent)														0.60%	293.60%	(0.10%)
Nondeductible expenses (as a percent)														0.20%	45.40%	0.80%
Foreign rate differential (as a percent)														0.40%	49.90%	0.50%
Income tax credits (as a percent)														(1.40%)	(160.90%)	(3.00%)
Domestic production activity deduction (as a percent)														(1.50%)		(5.20%)
Unrecognized tax benefits														(6.70%)
Change in tax laws (as a percent)														25.60%
Excess tax benefits on share-based compensation														(0.30%)	(134.30%)
Other (as a percent)														(1.20%)	70.80%	(0.10%)
Effective income tax rate (as a percent)														43.80%	199.50%	27.90%
Deferred tax assets:
Accrued expenses	1,085				1,869								$ 1,085	$ 1,085	$ 1,869
Share-based compensation expense	4,158				6,031								4,158	4,158	6,031
Reserve for returns	9,342				15,032								9,342	9,342	15,032
Reserves for rebates					11,194										11,194
Reserves for accounts receivable and inventory	5,425				2,026								5,425	5,425	2,026
Intangible impairment	1,337				2,176								1,337	1,337	2,176
Federal net operating loss	402				736								402	402	736
State net operating loss	4,495				2,944								4,495	4,495	2,944
Impairment on Cody note receivable	1,175				1,913								1,175	1,175	1,913
Accumulated amortization on intangible assets	10,868				25,505								10,868	10,868	25,505
Settlement Liability					6,019										6,019
Foreign net operating loss	880				736								880	880	736
Other	404				290								404	404	290
Total deferred tax asset	39,571				76,471								39,571	39,571	76,471
Valuation allowance	(8,120)				(6,391)								(8,120)	(8,120)	(6,391)
Total deferred tax asset less valuation allowance	31,451				70,080								31,451	31,451	70,080
Deferred tax liabilities:
Prepaid expenses	118				267								118	118	267
Property, plant and equipment	9,231				16,807								9,231	9,231	16,807
Other	39				253								39	39	253
Total deferred tax liability	9,388				17,327								9,388	9,388	17,327
Net deferred tax asset	$ 22,063				$ 52,753								$ 22,063	$ 22,063	$ 52,753