Litigation, Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Loss Contingency [Abstract]
Estimated recoverable amount	$ 429,544	$ 429,544	$ 432,067
ASU 2016-13 [Member]
Loss Contingency [Abstract]
Allowance for credit losses, before tax	16,500	16,500	15,000
Allowance for credit losses, net of tax	13,035	13,035	11,850
Allowance For Doubtful Accounts Receivable Period Increase Decrease, Before Tax	1,500	1,500
Additional allowance for expected credit losses, net of tax	$ 1,185	1,185
Charge incurred to operations, gross			30,230
Charge incurred to operations, net of tax			$ 23,882
Personnel Staffing Group d/b/a MVP Staffing [Member]
Loss Contingency [Abstract]
Per claim deductible amount		500
Damages sought		$ 0
Percentage of required collateral	110.00%	110.00%
Deductible receivables	$ 19,400	$ 19,400
Average monthly deductible invoices		786
Estimated recoverable amount	46,730	46,730
Personnel Staffing Group d/b/a MVP Staffing [Member] | Minimum [Member]
Loss Contingency [Abstract]
Loss fund	$ 4,000	$ 4,000