Income Taxes (Details - Effective Tax Rate)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Federal statutory tax rate	21.00%	21.00%	35.00%
State income taxes, net of federal tax benefit	5.00%	5.10%	4.20%
Disallowed executive compensation	0.30%	0.20%	0.10%
Change in valuation allowances	0.00%	0.00%	(0.10%)
Tax credits	(0.10%)	(0.10%)	(0.30%)
Estimated reserve for uncertain tax positions	0.70%	0.20%	(0.30%)
Deferred tax adjustments	0.50%	(0.50%)	(0.30%)
Tax reform adjustments	0.00%	0.00%	5.50%
Excess tax benefit on share-based compensation	(0.20%)	(0.60%)	(0.70%)
Other	0.40%	0.50%	(0.90%)
Effective tax rate	27.60%	25.80%	42.20%