Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands |
6 Months Ended | |||
|---|---|---|---|---|
Jun. 29, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
Dec. 29, 2018 |
|
| Summary of Significant Accounting Policies [Line Items] | ||||
| Operating lease, right-of-use assets | $ 13,592 | |||
| Operating lease, right-of-use liabilities | 13,734 | |||
| Contract asset, current | 1,956 | $ 2,851 | ||
| Contract Liabilities, current | 451 | $ 138 | ||
| Research and development costs charged to expense | $ 7,778 | $ 6,301 | ||
| Accounting Standards Update 2016-02 [Member] | ||||
| Summary of Significant Accounting Policies [Line Items] | ||||
| Operating lease, right-of-use assets | $ 13,918 | |||
| Operating lease, right-of-use liabilities | 13,918 | |||
| Cumulative-effect adjustment recognized in retained earnings | $ 134 | |||
| X | ||||||||||
- Definition Summary of significant accounting policies. No definition available.
|
| X | ||||||||||
- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|