Reportable Operating Segments (Details)	3 Months Ended		9 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Mar. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			6
Net sales	$ 938,735,000	$ 873,800,000	$ 1,757,779,000	$ 1,626,307,000
(Loss) income from operations	255,766,000	244,718,000	321,480,000	295,716,000
Total assets	1,888,351,000		1,888,351,000		$ 1,427,206,000
Unallocated cash and cash equivalents	616,864,000		616,864,000		589,692,000
Unallocated deferred tax assets, net	32,172,000		32,172,000		30,870,000
Reportable segments
Segment Reporting Information [Line Items]
Total assets	923,729,000		923,729,000		592,342,000
Reportable segments | UGG brand wholesale
Segment Reporting Information [Line Items]
Total assets	430,309,000		430,309,000		240,411,000
Reportable segments | HOKA brand wholesale
Segment Reporting Information [Line Items]
Total assets	116,096,000		116,096,000		94,157,000
Reportable segments | Teva brand wholesale
Segment Reporting Information [Line Items]
Total assets	54,052,000		54,052,000		76,370,000
Reportable segments | Sanuk brand wholesale
Segment Reporting Information [Line Items]
Total assets	46,864,000		46,864,000		71,285,000
Reportable segments | Other brands wholesale
Segment Reporting Information [Line Items]
Total assets	37,734,000		37,734,000		14,618,000
Reportable segments | Direct-to-Consumer
Segment Reporting Information [Line Items]
Total assets	238,674,000		238,674,000		95,501,000
Segment reconciling items
Segment Reporting Information [Line Items]
Intersegment profit			0
(Loss) income from operations	(73,813,000)	(66,049,000)	(198,080,000)	(184,437,000)
Unallocated other corporate assets	315,586,000		315,586,000		$ 214,302,000
Wholesale | UGG brand wholesale
Segment Reporting Information [Line Items]
Net sales	396,649,000	388,039,000	814,069,000	788,981,000
Wholesale | HOKA brand wholesale
Segment Reporting Information [Line Items]
Net sales	71,927,000	46,243,000	196,892,000	129,758,000
Wholesale | Teva brand wholesale
Segment Reporting Information [Line Items]
Net sales	14,406,000	20,087,000	62,328,000	69,161,000
Wholesale | Sanuk brand wholesale
Segment Reporting Information [Line Items]
Net sales	5,286,000	9,172,000	28,059,000	40,608,000
Wholesale | Other brands wholesale
Segment Reporting Information [Line Items]
Net sales	36,799,000	18,703,000	63,808,000	39,404,000
Wholesale | Reportable segments | UGG brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	147,189,000	141,080,000	292,293,000	280,978,000
Wholesale | Reportable segments | HOKA brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	15,110,000	8,791,000	40,522,000	22,689,000
Wholesale | Reportable segments | Teva brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	1,128,000	1,685,000	12,967,000	11,596,000
Wholesale | Reportable segments | Sanuk brand wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	(745,000)	(635,000)	1,428,000	3,856,000
Wholesale | Reportable segments | Other brands wholesale
Segment Reporting Information [Line Items]
(Loss) income from operations	8,192,000	4,513,000	15,282,000	10,150,000
Directly to Consumer | Direct-to-Consumer
Segment Reporting Information [Line Items]
Net sales	413,668,000	391,556,000	592,623,000	558,395,000
Directly to Consumer | Reportable segments | Direct-to-Consumer
Segment Reporting Information [Line Items]
(Loss) income from operations	$ 158,705,000	$ 155,333,000	$ 157,068,000	$ 150,884,000