Shares Used In Computing Diluted Net Income (Loss) Per Share - Shares Used In Computing Diluted Net Income (Loss) Per Share (Detail) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Shares Used In Computing Diluted Net Income Loss Per Share [Line Items]
Weighted average common shares outstanding used in calculating basic net income (loss) per share attributable to Viasat, Inc. common stockholders	73,544	66,576	72,549	64,554
Weighted average restricted stock units to acquire common stock as determined by application of the treasury stock method	942	132	809
Weighted average potentially issuable shares in connection with certain terms of the Viasat 401(k) Profit Sharing Plan and Employee Stock Purchase Plan	198	298	352
Weighted average shares used in computing diluted net income (loss) per share attributable to Viasat, Inc. common stockholders	74,872	67,006	73,862	64,554
Employee Stock Option [Member]
Shares Used In Computing Diluted Net Income Loss Per Share [Line Items]
Weighted average options to purchase common stock as determined by application of the treasury stock method	10		8
TSR Performance Stock Options [Member]
Shares Used In Computing Diluted Net Income Loss Per Share [Line Items]
Weighted average options to purchase common stock as determined by application of the treasury stock method	178		144