Shares Used in Computing Diluted Net Income per Share (Detail) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 28, 2012	Dec. 30, 2011	Dec. 28, 2012	Dec. 30, 2011
Earnings Per Share [Line Items]
Weighted average common shares outstanding used in calculating basic net (loss) income per share attributable to ViaSat, Inc. common stockholders	44,189	42,452	43,662	42,132
Weighted average options to purchase common stock as determined by application of the treasury stock method		1,352		1,371
Weighted average restricted stock units to acquire common stock as determined by application of the treasury stock method		422		407
Weighted average potentially issuable shares in connection with certain terms of the amended ViaSat 401(k) Profit Sharing Plan and Employee Stock Purchase Plan equivalents		107		105
Weighted average shares used in computing diluted net (loss) income per share attributable to ViaSat, Inc. common stockholders	44,189	44,333	43,662	44,015