Segment Disclosures - Summary of Segment Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenue	$ 157,022	$ 180,269	$ 177,466	$ 204,726	$ 146,652	$ 165,145	$ 168,296	$ 197,078	$ 719,483	$ 677,171	$ 612,689
Operating expenses	154,316	155,233	158,317	161,938	144,291	146,464	147,202	155,382	629,804	593,339	540,305
Gross margin	2,706	25,036	19,149	42,788	2,361	18,681	21,094	41,696	89,679	83,832	72,384
Corporate general & admin	6,790	8,889	8,306	10,198	7,821	8,944	7,649	9,984	34,183	34,398	30,209
Operating income (loss)	(4,084)	16,147	10,843	32,590	(5,460)	9,737	13,445	31,712	55,496	49,434	42,175
Other income (expense):
Interest expense	(2,991)	(3,123)	(3,577)	(3,433)	(3,358)	(3,815)	(4,145)	(4,056)	(13,124)	(15,374)	(14,999)
Gain on sale of operations, net	1,210	17	68	8	7	6	48	18	1,303	79	2,766
Other income, net	2,350	(1,368)	3,936	1,975	3,203	2,371	515	1,728	6,893	7,817	8,215
Total other income (expense)	569	(4,474)	427	(1,450)	(148)	(1,438)	(3,582)	(2,310)	(4,928)	(7,478)	(4,018)
Income (loss) from continuing operations before income tax expense	(3,515)	11,673	11,270	31,140	(5,608)	8,299	9,863	29,402	50,568	41,956	38,157
Financial Services [Member]
Segment Reporting Information [Line Items]
Revenue									465,130	441,787	396,346
Operating expenses									399,783	380,660	342,539
Gross margin									65,347	61,127	53,807
Operating income (loss)									65,347	61,127	53,807
Other income (expense):
Other income, net									417	491	2,064
Total other income (expense)									417	491	2,064
Income (loss) from continuing operations before income tax expense									65,764	61,618	55,871
Employee Services [Member]
Segment Reporting Information [Line Items]
Revenue									224,898	204,863	186,217
Operating expenses									186,002	168,696	155,311
Gross margin									38,896	36,167	30,906
Operating income (loss)									38,896	36,167	30,906
Other income (expense):
Interest expense									(31)	(24)	(30)
Other income, net									557	297	1,086
Total other income (expense)									526	273	1,056
Income (loss) from continuing operations before income tax expense									39,422	36,440	31,962
National Practices [Member]
Segment Reporting Information [Line Items]
Revenue									29,455	30,521	30,126
Operating expenses									26,798	27,589	26,713
Gross margin									2,657	2,932	3,413
Operating income (loss)									2,657	2,932	3,413
Other income (expense):
Other income, net									4	1	2
Total other income (expense)									4	1	2
Income (loss) from continuing operations before income tax expense									2,661	2,933	3,415
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating expenses									17,221	16,394	15,742
Gross margin									(17,221)	(16,394)	(15,742)
Corporate general & admin									34,183	34,398	30,209
Operating income (loss)									(51,404)	(50,792)	(45,951)
Other income (expense):
Interest expense									(13,093)	(15,350)	(14,969)
Gain on sale of operations, net									1,303	79	2,766
Other income, net									5,915	7,028	5,063
Total other income (expense)									(5,875)	(8,243)	(7,140)
Income (loss) from continuing operations before income tax expense									$ (57,279)	$ (59,035)	$ (53,091)