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.

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Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from contract modification which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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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.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

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Revenue - Narrative (Details) $ in Thousands	3 Months Ended	12 Months Ended
Revenue - Narrative (Details) $ in Thousands	Dec. 31, 2021 segment	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Disaggregation of Revenue [Line Items]
Number of reportable segments \| segment	2	2
Contract with customer, liability, revenue recognized		$ 4,300	$ 5,300	$ 4,200
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	85.80%	85.80%
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	14.10%	14.10%
Revenue, remaining performance obligation, expected timing of satisfaction, period	2 years	2 years
Accounting Standards Update 2014-09
Disaggregation of Revenue [Line Items]
Contract with customer, asset, cumulative catch-up adjustment to revenue, modification of contract		$ 200
Revenue from Contract with Customer, Product and Service Benchmark \| Revenue Timing of Transfer of Goods or Service \| Transferred over Time
Disaggregation of Revenue [Line Items]
Concentration risk, percentage		91.00%	90.00%	90.00%
Revenue from Contract with Customer, Product and Service Benchmark \| Revenue Timing of Transfer of Goods or Service \| Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Concentration risk, percentage		9.00%	10.00%	10.00%
Federal Government \| Revenue from Contract with Customer, Product and Service Benchmark \| Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration risk, percentage		96.10%	95.40%	93.70%
Federal Government \| Accounts Receivable \| Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration risk, percentage		97.30%