Fair Value (Details - narrative items) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Fair Value - Other Details [Line Items]
Funds held directly managed investments carried at fair value	$ 426,537	$ 399,899
Cash and cash equivalents	1,749,851	1,577,097	$ 1,413,799	$ 1,313,468
Accrued investment income	134,735	141,672
Fair Value Assets Level 2 To Level 1 Transfers Amount	0		$ 0
Funds held directly managed [Member]
Fair Value - Other Details [Line Items]
Cash and cash equivalents	39,000	64,600
Accrued investment income	4,400	4,500
Other net assets, at cost, within funds-held	109,700	70,700
Trading securities [Member] | Other invested assets [Member]
Fair Value - Other Details [Line Items]
Carrying amount of other invested assets not at fair value	$ 203,800	$ 208,300