Quarterly Results of Operations (Unaudited) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Condensed Income Statements, Captions [Line Items]
Deferred Tax Assets, Valuation Allowance									$ 5,800	$ 112,700
Net sales	$ 293,174	$ 294,741	$ 327,397	$ 345,242	$ 355,794	$ 350,175	$ 349,233	$ 327,616	1,260,554	1,382,818	$ 1,200,181
Gross Profit	92,009	93,181	113,670	121,628	126,406	123,750	113,565	94,821
Operating income (loss)	11,728	28,648	49,090	58,400	54,057	61,616	50,000	35,176	147,866	200,849	112,852
Net income (loss)	$ (301)	16,602	$ (15,260)	$ 40,340	$ 93,420	$ 40,806	$ 37,141	$ 35,220	41,381	206,587	254,127
U.S. Class Action Complaint [Member]
Condensed Income Statements, Captions [Line Items]
Litigation Settlement, Amount Awarded to Other Party		$ 62,000
USA and Japan [Member]
Condensed Income Statements, Captions [Line Items]
Deferred Tax Assets, Valuation Allowance										(50,100)
UNITED STATES
Condensed Income Statements, Captions [Line Items]
Net sales									$ 246,821	$ 292,980	$ 233,133