Stock Compensation - Annual Awards (Details) - Stock Incentive Plan 2015 - $ / shares	6 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Annual RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	38,307	59,235
Weighted-average grant date fair value (in dollars per share)	$ 173.65	$ 115.65
Annual PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	19,938	31,320
Weighted-average grant date fair value (in dollars per share)	$ 174.36	$ 116.34
Annual RSUs and Annual PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	58,245	90,555
Weighted-average grant date fair value (in dollars per share)	$ 173.89	$ 115.89

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_PlanNameAxis=deck_StockIncentivePlan2015Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=deck_AnnualRestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=deck_AnnualPerformancebasedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=deck_AnnualRSUsandAnnualPSUsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: