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Business Segment Information - Additional Information (Details) - Sales Revenue, Net - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Various Governments
Segment Reporting Information [Line Items]
Concentration risk percentage	71.00%	71.00%	71.00%
U.S. Federal Government
Segment Reporting Information [Line Items]
Concentration risk percentage	36.60%	33.20%	31.30%

X

- 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

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+ References

No definition available.

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