Income Taxes (Details - Effective Tax Rate)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Federal statutory rate	35.00%	35.00%	35.00%
State income taxes, net of federal tax benefit	0.20%	2.00%	2.80%
Difference between statutory rate and foreign effective tax rate	(2.40%)	(1.00%)	(1.40%)
Tax exempt income	(0.50%)	(0.10%)	(0.30%)
Disallowed interest expense	6.50%	0.60%	0.90%
Change in valuation allowance	0.10%	2.20%	1.10%
Tax credits	(3.80%)	(0.60%)	(1.80%)
Estimated reserve for uncertain tax positions	4.70%	(0.30%)	(2.60%)
Deferred tax adjustments	3.50%	(3.40%)	4.50%
Tax on undistributed earnings and profits in certain foreign subsidiaries	3.90%	1.10%	2.40%
Settled IRS Examination	(241.50%)	0.00%	0.00%
Tax impact of exit of market making business	0.00%	0.00%	16.40%
Other	(0.40%)	(0.30%)	(1.10%)
Effective tax rate	(194.70%)	35.20%	55.90%
Effective Income Tax Rate Reconciliation New York City Tax Legislative Changes	(5.80%)
Effective Income Tax Rate Reconciliation New York State Tax Legislative Changes		(1.80%)