Segment Disclosures - Summary of Segment Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Revenue	$ 187,102	$ 180,269	$ 586,010	$ 562,461
Operating expenses	159,175	155,233	493,156	475,488
Gross margin	27,927	25,036	92,854	86,973
Corporate general & admin	8,043	8,889	24,523	27,393
Operating income (loss)	19,884	16,147	68,331	59,580
Other income (expense):
Interest expense	(1,840)	(3,123)	(7,665)	(10,133)
Gain on sale of operations, net	5	17	106	93
Other income (expense), net	(1,673)	(1,368)	60	4,543
Total other income (expense)	(3,508)	(4,474)	(7,499)	(5,497)
Income (loss) from continuing operations before income tax expense	16,376	11,673	60,832	54,083
Operating Segments [Member] | Financial Services [Member]
Segment Reporting Information [Line Items]
Revenue	118,354	115,931	378,857	372,832
Operating expenses	101,979	98,987	312,942	305,333
Gross margin	16,375	16,944	65,915	67,499
Operating income (loss)	16,375	16,944	65,915	67,499
Other income (expense):
Other income (expense), net	475	191	575	232
Total other income (expense)	475	191	575	232
Income (loss) from continuing operations before income tax expense	16,850	17,135	66,490	67,731
Operating Segments [Member] | Employee Services [Member]
Segment Reporting Information [Line Items]
Revenue	61,293	56,891	184,968	167,479
Operating expenses	51,043	47,194	153,813	138,865
Gross margin	10,250	9,697	31,155	28,614
Operating income (loss)	10,250	9,697	31,155	28,614
Other income (expense):
Interest expense	(9)	(7)	(28)	(23)
Other income (expense), net	462	97	660	472
Total other income (expense)	453	90	632	449
Income (loss) from continuing operations before income tax expense	10,703	9,787	31,787	29,063
Operating Segments [Member] | National Practices [Member]
Segment Reporting Information [Line Items]
Revenue	7,455	7,447	22,185	22,150
Operating expenses	6,644	6,585	19,894	19,902
Gross margin	811	862	2,291	2,248
Operating income (loss)	811	862	2,291	2,248
Other income (expense):
Other income (expense), net	2	4	3	4
Total other income (expense)	2	4	3	4
Income (loss) from continuing operations before income tax expense	813	866	2,294	2,252
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating expenses	(491)	2,467	6,507	11,388
Gross margin	491	(2,467)	(6,507)	(11,388)
Corporate general & admin	8,043	8,889	24,523	27,393
Operating income (loss)	(7,552)	(11,356)	(31,030)	(38,781)
Other income (expense):
Interest expense	(1,831)	(3,116)	(7,637)	(10,110)
Gain on sale of operations, net	5	17	106	93
Other income (expense), net	(2,612)	(1,660)	(1,178)	3,835
Total other income (expense)	(4,438)	(4,759)	(8,709)	(6,182)
Income (loss) from continuing operations before income tax expense	$ (11,990)	$ (16,115)	$ (39,739)	$ (44,963)