Receivables, net (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Current and long-term receivables balances
Accounts receivable	$ 179,250	$ 164,223
Unbilled accounts receivable	126,165	136,795
Long-term receivables	3,082	5,972
Total receivables	308,497	306,990
Less allowance for doubtful accounts	(869)	(3,936)	$ 0	$ 0
Total receivables, net	$ 307,628	$ 303,054

Accounts receivable and installment contract receivables

No definition available.

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- Definition

Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of current and noncurrent accounts receivable due from other than related parties.

+ References

No definition available.

+ Details

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- Definition

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

+ References

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-Publisher FASB
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- Definition

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

+ References

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- References

No definition available.

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- Definition

Amount of allowance for credit loss on accounts receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 210
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- Definition

Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

+ References

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+ Details

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