Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Statement of Income and Comprehensive Income [Abstract]
Net income before noncontrolling interests	$ 101,008	$ 76,371	$ 345,144	$ 274,086
Other comprehensive income (loss):
Change in unrealized foreign exchange gains (losses)	26,056	(30,957)	24,382	(21,104)
Unrealized holding gains (losses) on investment securities arising during the period, net of taxes	79,772	39,031	188,263	125,085
Reclassification adjustment for net investment losses included in net income, net of taxes	(14,811)	(13,784)	(61,743)	(46,910)
Change in unrecognized pension obligation, net of taxes	823	707	2,470	2,118
Other comprehensive income (loss)	91,840	(5,003)	153,372	59,189
Comprehensive income	192,848	71,368	498,516	333,275
Comprehensive (income) loss to the noncontrolling interests	(104)	40	(112)	87
Comprehensive income to common stockholders	$ 192,744	$ 71,408	$ 498,404	$ 333,362