Fair Value (Details - narrative items) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Fair Value - Other Details [Line Items]
Funds held directly managed investments carried at fair value	$ 424,689		$ 424,689		$ 472,593
Cash and cash equivalents	1,492,997	$ 1,208,220	1,492,997	$ 1,208,220	1,313,468	$ 1,496,485
Accrued investment income	139,772		139,772		158,737
Fair Value Assets Level 2 To Level 1 Transfers Amount	0	0	0	0
Funds held directly managed [Member]
Fair Value - Other Details [Line Items]
Cash and cash equivalents	58,100		58,100		42,300
Accrued investment income	4,800		4,800		5,700
Other net assets	107,300		107,300		88,300
Trading securities [Member] | Other invested assets [Member]
Fair Value - Other Details [Line Items]
Carrying amount of other invested assets not at fair value	209,200		209,200		$ 187,300
Other invested assets [Member] | Derivatives, net [Member]
Fair Value - Other Details [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances	$ 0	$ 200	$ 0	$ 900