Basic and Diluted Net Loss Per Common Share - Narrative (Details) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
2.125% Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	$ 402,500	$ 402,500
Debt instrument interest percentage	2.125%
Senior notes \| 2.5% Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	$ 200,000
Debt instrument interest percentage	2.50%

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant