Reportable Segments - Schedule (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 338,861	$ 329,535	$ 665,599	$ 646,976
Gross profit	101,026	100,220	194,202	192,729
Operating expenses and other expenses	79,962	79,851	162,348	161,743
Income from continuing operations, before income taxes	21,064	20,369	31,854	30,986
Tech
Segment Reporting Information [Line Items]
Revenue	265,305	249,763	520,948	486,260
Gross profit	74,172	71,830	142,995	137,178
FA
Segment Reporting Information [Line Items]
Revenue	73,556	79,772	144,651	160,716
Gross profit	$ 26,854	$ 28,390	$ 51,207	$ 55,551

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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