UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Net service revenues	$ 337,353	$ 302,758	$ 649,964	$ 584,782
Direct costs of services	231,315	208,372	449,186	406,870
Gross profit	106,038	94,386	200,778	177,912
Selling, general and administrative expenses	83,195	78,391	165,547	152,128
Depreciation and amortization	2,426	2,393	4,823	4,749
Income from operations	20,417	13,602	30,408	21,035
Other expense, net	991	470	1,444	807
Income from continuing operations, before income taxes	19,426	13,132	28,964	20,228
Income tax expense	7,833	5,179	11,586	7,886
Income from continuing operations	11,593	7,953	17,378	12,342
Income from discontinued operations, net of income taxes	0	2,750	0	4,610
Net income	11,593	10,703	17,378	16,952
Other comprehensive income (loss):
Defined benefit pension and post-retirement plans, net of tax	1	2	2	(33)
Comprehensive income	$ 11,594	$ 10,705	$ 17,380	$ 16,919
Earnings per share – basic:
From continuing operations (in dollars per share)	$ 0.41	$ 0.24	$ 0.62	$ 0.38
From discontinued operations (in dollars per share)	0.00	0.09	0.00	0.14
Earnings per share – basic (in dollars per share)	0.41	0.33	0.62	0.52
Earnings per share – diluted:
From continuing operations (in dollars per share)	0.41	0.24	0.61	0.37
From discontinued operations (in dollars per share)	0.00	0.09	0.00	0.14
Earnings per share – diluted (in dollars per share)	$ 0.41	$ 0.33	$ 0.61	$ 0.51
Weighted average shares outstanding – basic (in shares)	28,134	32,481	28,204	32,729
Weighted average shares outstanding – diluted (in shares)	28,337	32,710	28,407	32,944
Dividends declared per share (in dollars per share)	$ 0.11	$ 0.10	$ 0.22	$ 0.20