v2.4.0.8
Document and Entity Information
3 Months Ended
Mar. 31, 2015
Entity Information [Line Items]  
Document Type 10-Q
Amendment Flag false
Document Period End Date Mar. 31, 2015
Document Fiscal Year Focus 2015
Document Fiscal Period Focus Q1
Trading Symbol UA
Entity Registrant Name UNDER ARMOUR, INC.
Entity Central Index Key 0001336917
Current Fiscal Year End Date --12-31
Entity Filer Category Large Accelerated Filer
Class A Common Stock [Member]
 
Entity Information [Line Items]  
Entity Common Stock, Shares Outstanding 179,386,971
Class B Convertible Common Stock [Member]
 
Entity Information [Line Items]  
Entity Common Stock, Shares Outstanding 36,150,000