RECEIVABLES (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
ConcentrationRiskLineItems
Net unbilled receivables	$ 235,018	$ 221,959
GovernmentContractsConcentrationRiskMember
ConcentrationRiskLineItems
ConcentrationRiskPercentage	53.00%	43.00%
Accounts Receivable, before Allowance for Credit Loss	$ 352,700	$ 343,500
Net unbilled receivables	$ 198,600	$ 195,700

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

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044

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