Litigation, Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Loss Contingency [Abstract]
Estimated recoverable amount	$ 455,564		$ 455,564	$ 455,564	$ 432,067
Allowance for credit losses, net of tax	1,035		1,035	1,035
ASU 2016-13 [Member]
Loss Contingency [Abstract]
Allowance for credit losses, before tax	16,500		16,500	16,500	15,000
Allowance for credit losses, net of tax	13,035		$ 13,035	13,035	11,850
Additional allowance for expected credit losses, gross	$ 0	$ 1,500
Additional allowance for expected credit losses, net of tax		$ 1,185
Charge incurred to operations, gross					30,500
Charge incurred to operations, net of tax					$ 24,095
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%	110.00%
Deductible receivables	$ 21,780		$ 21,780	$ 21,780
Average monthly deductible invoices			740
Estimated recoverable amount	47,000		47,000	47,000
Personnel Staffing Group d/b/a MVP Staffing [Member] | Minimum [Member]
Loss Contingency [Abstract]
Loss fund	$ 4,000		$ 4,000	$ 4,000