Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Unrealized gains (losses) on investments arising during the period, deferred tax	$ 617	$ 4,937
Reclassification adjustment for net realized (gains) losses included in net income, deferred tax	1,770	344
Non credit other-than-temporary impairments arising during the period, deferred tax	150	241
Reclassification adjustment for non-credit other-than-temporary impairment losses recognized in net income, deferred tax		16
Change in foreign currency translation gains (losses), deferred tax	$ 1,543	$ 1,399