Credit Facility (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Apr. 28, 2017	Dec. 31, 2016
Line of Credit Facility [Line Items]
Long-term debt – credit facility	$ 131,966,000		$ 111,547,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit maximum borrowing capacity	170,000,000
Line of credit current borrowing capacity available from amendment	$ 50,000,000
Line of credit maximum borrowing percentage of accounts receivable	85.00%
Line of credit maximum borrowing percentage of employee placement accounts	80.00%
Line of credit maximum borrowings percentage of corporate headquarters	80.00%
Quarterly reduction of additional corporate headquarters borrowing base	1.25%
Line of credit facility basis spread on variable rate under condition two	0.50%
Line of credit basis spread on variable rate under condition one	1.25%
Line of credit basis spread on variable rate under condition three	0.125%
Line of credit unused capacity commitment fee percentage threshold	35.00%
Percentage of commitment of all lenders as condition to maintain min fixed charge coverage ratio	10.00%
Amount of commitment of all lenders as condition to maintain min fixed charge coverage ratio	$ 11,000,000
Line of credit limit on equity security repurchases, max percent availability of borrowing capacity	15.00%
Line of credit limit on equity security repurchases availability of borrowing capacity	$ 15,000,000
Line of credit covenant limit on distributions max percent availability of borrowing capacity	12.50%
Line of credit covenant limit on distributions availability of borrowing capacity	$ 20,600,000
Line of credit remaining borrowing capacity	$ 20,900,000
Revolving Credit Facility | Subsequent Event
Line of Credit Facility [Line Items]
Line of credit remaining borrowing capacity		$ 27,300,000
Long-term debt – credit facility		$ 125,600,000
Revolving Credit Facility | Below Threshold
Line of Credit Facility [Line Items]
Line of credit unused capacity commitment fee percentage	0.35%
Revolving Credit Facility | Above Threshold
Line of Credit Facility [Line Items]
Line of credit unused capacity commitment fee percentage	0.25%
Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility sub limit for letters of credit	$ 15,000,000