Receivables, net (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Current and long-term receivables balances
Accounts receivable	$ 130,796	$ 164,223
Unbilled accounts receivable	107,962	136,795
Long-term receivables	2,140	5,972
Total receivables	240,898	306,990
Less allowance for doubtful accounts	(1,149)	(3,936)
Total receivables, net	$ 239,749	$ 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

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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- References

No definition available.

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- Definition

Amount due from customers or clients, more than one year from the balance sheet date, for goods or services that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

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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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