Reportable Segments - Schedule (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 345,558	$ 326,584	$ 1,011,157	$ 973,560
Gross profit	102,811	96,045	297,013	288,774
Operating and other expenses	81,530	77,150	243,878	238,893
Income from continuing operations, before income taxes	21,281	18,895	53,135	49,881
Tech
Segment Reporting Information [Line Items]
Revenue	271,999	251,079	792,947	737,339
Gross profit	76,436	69,522	219,431	206,700
FA
Segment Reporting Information [Line Items]
Revenue	73,559	75,505	218,210	236,221
Gross profit	$ 26,375	$ 26,523	$ 77,582	$ 82,074

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

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