Segment Disclosures - Summary of Segment Information (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Revenue	$ 164,412	$ 187,102	$ 185,042	$ 213,866	$ 157,022	$ 180,269	$ 177,466	$ 204,726	$ 750,422	$ 719,483	$ 677,171
Operating expenses	160,788	159,175	163,117	170,864	154,316	155,233	158,317	161,938	653,944	629,804	593,339
Gross margin	3,624	27,927	21,925	43,002	2,706	25,036	19,149	42,788	96,478	89,679	83,832
Corporate general & admin	8,071	8,043	6,615	9,865	6,790	8,889	8,306	10,198	32,594	34,183	34,398
Operating income (loss)	(4,447)	19,884	15,310	33,137	(4,084)	16,147	10,843	32,590	63,884	55,496	49,434
Other income (expense):
Interest expense	(1,237)	(1,840)	(2,848)	(2,977)	(2,991)	(3,123)	(3,577)	(3,433)	(8,902)	(13,124)	(15,374)
Gain on sale of operations, net	(22)	5	45	56	1,210	17	68	8	84	1,303	79
Other income, net	2,706	(1,673)	(1,126)	2,859	2,350	(1,368)	3,936	1,975	2,766	6,893	7,817
Total other income (expense)	1,447	(3,508)	(3,929)	(62)	569	(4,474)	427	(1,450)	(6,052)	(4,928)	(7,478)
Income (loss) from continuing operations before income tax expense	$ (3,000)	$ 16,376	$ 11,381	$ 33,075	$ (3,515)	$ 11,673	$ 11,270	$ 31,140	57,832	50,568	41,956
Operating Segments [Member] | Financial Services [Member]
Segment Reporting Information [Line Items]
Revenue									476,396	465,130	441,787
Operating expenses									412,211	399,783	380,660
Gross margin									64,185	65,347	61,127
Operating income (loss)									64,185	65,347	61,127
Other income (expense):
Other income, net									739	417	491
Total other income (expense)									739	417	491
Income (loss) from continuing operations before income tax expense									64,924	65,764	61,618
Operating Segments [Member] | Employee Services [Member]
Segment Reporting Information [Line Items]
Revenue									244,493	224,898	204,863
Operating expenses									202,787	186,002	168,696
Gross margin									41,706	38,896	36,167
Operating income (loss)									41,706	38,896	36,167
Other income (expense):
Interest expense									(35)	(31)	(24)
Other income, net									1,116	557	297
Total other income (expense)									1,081	526	273
Income (loss) from continuing operations before income tax expense									42,787	39,422	36,440
Operating Segments [Member] | National Practices [Member]
Segment Reporting Information [Line Items]
Revenue									29,533	29,455	30,521
Operating expenses									26,417	26,798	27,589
Gross margin									3,116	2,657	2,932
Operating income (loss)									3,116	2,657	2,932
Other income (expense):
Other income, net									4	4	1
Total other income (expense)									4	4	1
Income (loss) from continuing operations before income tax expense									3,120	2,661	2,933
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating expenses									12,529	17,221	16,394
Gross margin									(12,529)	(17,221)	(16,394)
Corporate general & admin									32,594	34,183	34,398
Operating income (loss)									(45,123)	(51,404)	(50,792)
Other income (expense):
Interest expense									(8,867)	(13,093)	(15,350)
Gain on sale of operations, net									84	1,303	79
Other income, net									907	5,915	7,028
Total other income (expense)									(7,876)	(5,875)	(8,243)
Income (loss) from continuing operations before income tax expense									$ (52,999)	$ (57,279)	$ (59,035)