Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Net income	$ 529,324	$ 497,161	$ 498,866
Unrealized gains (losses) on securities:
Unrealized holding gains (losses) arising during period	657,954	882,467	615,503
Reclassification adjustment for (gains) losses on securities included in net income	(41,745)	(27,771)	(38,170)
Reclassification adjustment for amortization of (discount) premium	462	(1,880)	(3,820)
Foreign exchange adjustment on securities marked to market	(4,334)	3,510	(7,735)
Unrealized gains (losses) on securities	612,337	856,326	565,778
Unrealized gains (losses), adjustment to deferred acquisition costs	7,234	(28,292)	(31,975)
Unrealized gains (losses) on other assets	2,517	366	0
Total unrealized investment gains (losses)	622,088	828,400	533,803
Less applicable taxes	(217,726)	(289,941)	(186,832)
Unrealized gains (losses), net of tax	404,362	538,459	346,971
Foreign exchange translation adjustments, other than securities	3,487	(3,261)	5,006
Less applicable taxes	(1,118)	699	(1,752)
Foreign exchange translation adjustments, other than securities, net of tax	2,369	(2,562)	3,254
Pension adjustments:
Amortization of pension costs	14,799	12,146	10,857
Plan amendments	(3,452)	0	0
Experience gain (loss)	(59,613)	(26,106)	(23,086)
Pension adjustments	(48,266)	(13,960)	(12,229)
Less applicable taxes	16,894	4,887	4,279
Pension adjustments, net of tax	(31,372)	(9,073)	(7,950)
Other comprehensive income (loss)	375,359	526,824	342,275
Comprehensive income (loss)	$ 904,683	$ 1,023,985	$ 841,141