Deferred Revenue and Other Contract Liabilities - Changes in Deferred Revenue (Details) $ in Thousands	3 Months Ended
Mar. 30, 2019 USD ($)
Movement in Deferred Revenue [Roll Forward]
Deferred revenue, beginning of the period	$ 10,883
Revenue deferred during the period	1,573
Recognition of revenue deferred in prior periods	(1,496)
Deferred revenue, end of the period	$ 10,960

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

No definition available.

Name:	us-gaap_DeferredRevenueAdditions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration