Segment Reporting (Tables)

9 Months Ended

Sep. 30, 2016

Segment Reporting Information [Line Items]

Schedule of Segment Reporting Information, by Segment



	Three Months Ended									Three Months Ended
	September 30, 2016									September 30, 2015
	Apex		Oxford		Corporate⁽¹⁾			Total		Apex		Oxford		Corporate⁽¹⁾			Total
Revenues	$	473,546	$	155,855	$	—		$	629,401	$	422,632	$	149,491	$	—		$	572,123
Gross profit	143,681		63,439		—			207,120		129,232		62,172		—			191,404
Operating income	53,982		14,429		(13,001		)	55,410		47,988		16,602		(13,125		)	51,465
Amortization	8,590		1,152		—			9,742		9,732		1,593		—			11,325



	Nine Months Ended									Nine Months Ended
	September 30, 2016									September 30, 2015
	Apex		Oxford		Corporate⁽¹⁾			Total		Apex		Oxford		Corporate⁽¹⁾			Total
Revenues	$	1,360,424	$	459,105	$	—		$	1,819,529	$	1,059,083	$	428,408	$	—		$	1,487,491
Gross profit	407,990		188,998		—			596,988		307,658		178,155		—			485,813
Operating income	144,158		41,045		(41,332		)	143,871		105,149		45,140		(41,043		)	109,246
Amortization	25,770		4,148		—			29,918		18,638		4,513		—			23,151


(1)	Corporate expenses primarily consist of consolidated stock-based compensation expense, compensation for corporate employees, acquisition, integration and strategic planning expenses, public company expenses, and depreciation expense for corporate assets.

Revenue by Type [Table Text Block]

The following table presents revenues by type (in thousands):



	Three Months Ended								Nine Months Ended
	September 30,								September 30,
	2016		%		2015		%		2016		%		2015		%
Revenues:
Assignment	$	596,437	94.8	%	$	539,383	94.3	%	$	1,720,312	94.5	%	$	1,402,116	94.3	%
Permanent placement	32,964		5.2	%	32,740		5.7	%	99,217		5.5	%	85,375		5.7	%
	$	629,401	100.0	%	$	572,123	100.0	%	$	1,819,529	100.0	%	$	1,487,491	100.0	%

Schedule of Revenue by Geographical Areas

The Company operates internationally, with operations mainly in the United States, Europe, and Canada. The following table presents revenues by geographic location (in thousands):



	Three Months Ended								Nine Months Ended
	September 30,								September 30,
	2016		%		2015		%		2016		%		2015		%
Revenues:
Domestic	$	599,991	95.3	%	$	546,747	95.6	%	$	1,732,594	95.2	%	$	1,420,492	95.5	%
Foreign	29,410		4.7	%	25,376		4.4	%	86,935		4.8	%	66,999		4.5	%
	$	629,401	100.0	%	$	572,123	100.0	%	$	1,819,529	100.0	%	$	1,487,491	100.0	%