Product Warranty - Additional Information (Detail)	3 Months Ended
Jun. 30, 2018
Product Warranties Disclosures [Abstract]
Maximum warranty periods provided on limited warranty	5 years

Maximum warranty periods provided on limited warranties.

No definition available.

Name:	vsat_ProductsWarrantyPeriodMaximum
Namespace Prefix:	vsat_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration