Reportable Operating Segments (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Mar. 31, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			6
Net sales	$ 1,077,759	$ 938,735	$ 1,984,453	$ 1,757,779
(Loss) income from operations	328,655	255,766	449,560	321,480
Total assets	2,387,850		2,387,850		$ 1,765,118
Unallocated cash and cash equivalents	1,156,556		1,156,556		649,436
Unallocated deferred tax assets, net	27,546		27,546		28,233
Reportable segments
Segment Reporting Information [Line Items]
Total assets	887,480		887,480		775,840
Reportable segments | UGG brand wholesale
Segment Reporting Information [Line Items]
Total assets	383,681		383,681		245,239
Reportable segments | HOKA brand wholesale
Segment Reporting Information [Line Items]
Total assets	142,201		142,201		124,958
Reportable segments | Teva brand wholesale
Segment Reporting Information [Line Items]
Total assets	46,893		46,893		90,305
Reportable segments | Sanuk brand wholesale
Segment Reporting Information [Line Items]
Total assets	37,020		37,020		50,314
Reportable segments | Other brands wholesale
Segment Reporting Information [Line Items]
Total assets	36,082		36,082		21,535
Reportable segments | Direct-to-Consumer
Segment Reporting Information [Line Items]
Total assets	241,603		241,603		243,489
Segment reconciling items
Segment Reporting Information [Line Items]
(Loss) income from operations	(87,742)	(73,813)	(214,390)	(198,080)
Unallocated cash and cash equivalents	1,156,556		1,156,556		649,436
Unallocated deferred tax assets, net	27,546		27,546		28,233
Corporate
Segment Reporting Information [Line Items]
Unallocated other corporate assets	316,268		316,268		$ 311,609
Wholesale | UGG brand wholesale
Segment Reporting Information [Line Items]
Net sales	408,859	396,649	744,281	814,069
Wholesale | HOKA brand wholesale
Segment Reporting Information [Line Items]
Net sales	100,893	71,927	279,629	196,892
Wholesale | Teva brand wholesale
Segment Reporting Information [Line Items]
Net sales	12,107	14,406	51,264	62,328
Wholesale | Sanuk brand wholesale
Segment Reporting Information [Line Items]
Net sales	3,829	5,286	17,142	28,059
Wholesale | Other brands wholesale
Segment Reporting Information [Line Items]
Net sales	32,182	36,799	60,489	63,808
Wholesale | Reportable segments | UGG brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	158,358	147,189	261,349	292,293
Wholesale | Reportable segments | HOKA brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	26,995	15,110	78,056	40,522
Wholesale | Reportable segments | Teva brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	1,029	1,128	9,993	12,967
Wholesale | Reportable segments | Sanuk brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	17	(745)	1,644	1,428
Wholesale | Reportable segments | Other brands wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	9,256	8,192	17,855	15,282
Directly to Consumer | Direct-to-Consumer
Segment Reporting Information [Line Items]
Net sales	519,889	413,668	831,648	592,623
Directly to Consumer | Reportable segments | Direct-to-Consumer
Segment Reporting Information [Line Items]
(Loss) income from operations	$ 220,742	$ 158,705	$ 295,053	$ 157,068