Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred tax liabilities:
Prepaid assets	$ (3,952,000)	$ (9,291,000)
Depreciation	(1,741,000)	(8,083,000)
Software development costs	(2,699,000)	(2,252,000)
Total deferred tax liabilities	(8,392,000)	(19,626,000)
Deferred tax assets:
Accrued incentive compensation	8,818,000	7,204,000
Net operating loss carryforward	1,463,000	1,556,000
Workers’ compensation accruals	7,586,000	6,308,000
Accrued rent	1,229,000	1,058,000
Stock-based compensation	4,553,000	3,615,000
Intangibles	1,159,000	1,575,000
Minority investment impairment	1,016,000	1,003,000
Other	564,000	551,000
Total deferred tax assets	26,388,000	22,870,000
Valuation allowance	(1,020,000)	(1,003,000)
Total net deferred tax assets	25,368,000	21,867,000
Net deferred tax assets	16,976,000	2,241,000
Current income tax expense:
Federal	35,221,000	18,034,000	$ 20,476,000
State	5,741,000	3,322,000	3,512,000
Total current income tax expense	40,962,000	21,356,000	23,988,000
Deferred income tax (benefit) expense:
Federal	(13,632,000)	(1,764,000)	(2,258,000)
State	(1,101,000)	31,000	(30,000)
Total deferred income tax benefit	(14,733,000)	(1,733,000)	(2,288,000)
Total income tax expense	26,229,000	19,623,000	21,700,000
Net income tax expense (benefit) on nonqualified stock option exercises	$ 2,216,000	488,000	1,259,000
Prior Period Reclassification Adjustment		6,300,000
Reconciliation of income tax expense [Abstract]
Assumed income tax rate (in hundredths)	35.00%
Expected income tax expense at 35%	$ 22,967,000	16,670,000	18,806,000
State income taxes, net of federal benefit	2,696,000	2,204,000	2,286,000
Nondeductible expenses	1,669,000	1,939,000	1,993,000
Section 199 benefits	(627,000)	(592,000)	(2,531,000)
Expense Management non-cash impairment	0	0	797,000
Valuation allowance related to TRE impairment	0	0	938,000
Research and development credit	(530,000)	(455,000)	(534,000)
Other, net	54,000	(143,000)	(55,000)
Total income tax expense	26,229,000	19,623,000	21,700,000
Business Acquisition [Line Items]
Section 199 tax benefits for the tax year 2013			(500,000)
Section 199 Tax Benefits for Tax Years 2009 to 2012			(2,000,000)
Liability for Uncertain Tax Positions, Current	0	$ 0	$ 0
ExpensAble [Member]
Business Acquisition [Line Items]
Operating Loss Carryforwards	$ 3,900,000
Minimum [Member] | ExpensAble [Member]
Business Acquisition [Line Items]
Net operating loss carryforwards, expiration date	Jan. 01, 2022
Maximum [Member] | ExpensAble [Member]
Business Acquisition [Line Items]
Net operating loss carryforwards, expiration date	Jan. 01, 2030