Segment Disclosures - Summary of Segment Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Revenue	$ 213,866us-gaap_Revenues	$ 204,726us-gaap_Revenues
Operating expenses	170,864us-gaap_CostOfRevenue	161,938us-gaap_CostOfRevenue
Gross margin	43,002us-gaap_GrossProfit	42,788us-gaap_GrossProfit
Corporate general & admin	9,865us-gaap_GeneralAndAdministrativeExpense	10,198us-gaap_GeneralAndAdministrativeExpense
Operating income (loss)	33,137us-gaap_OperatingIncomeLoss	32,590us-gaap_OperatingIncomeLoss
Other income (expense):
Interest expense	(2,977)us-gaap_InterestExpense	(3,433)us-gaap_InterestExpense
Gain on sale of operations, net	56	8
Other income, net	2,859us-gaap_OtherNonoperatingIncomeExpense	1,975us-gaap_OtherNonoperatingIncomeExpense
Total other income (expense)	(62)us-gaap_NonoperatingIncomeExpense	(1,450)us-gaap_NonoperatingIncomeExpense
Income (loss) from continuing operations before income tax expense	33,075	31,140
Financial Services [Member]
Segment Reporting Information [Line Items]
Revenue	143,832	141,238
Operating expenses	108,618	105,762
Gross margin	35,214	35,476
Operating income (loss)	35,214	35,476
Other income (expense):
Other income, net	99	99
Total other income (expense)	99	99
Income (loss) from continuing operations before income tax expense	35,313	35,575
Employee Services [Member]
Segment Reporting Information [Line Items]
Revenue	62,651	56,109
Operating expenses	51,528	45,735
Gross margin	11,123	10,374
Operating income (loss)	11,123	10,374
Other income (expense):
Interest expense	(9)	(8)
Other income, net	117	286
Total other income (expense)	108	278
Income (loss) from continuing operations before income tax expense	11,231	10,652
National Practices [Member]
Segment Reporting Information [Line Items]
Revenue	7,383	7,379
Operating expenses	6,601	6,634
Gross margin	782	745
Operating income (loss)	782	745
Other income (expense):
Income (loss) from continuing operations before income tax expense	782	745
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating expenses	4,117	3,807
Gross margin	(4,117)	(3,807)
Corporate general & admin	9,865	10,198
Operating income (loss)	(13,982)	(14,005)
Other income (expense):
Interest expense	(2,968)	(3,425)
Gain on sale of operations, net	56	8
Other income, net	2,643	1,590
Total other income (expense)	(269)	(1,827)
Income (loss) from continuing operations before income tax expense	$ (14,251)	$ (15,832)

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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-Name Accounting Standards Codification

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-Publisher FASB

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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