Consolidated Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Income and Comprehensive Income [Abstract]
Net earnings	$ 112,917us-gaap_NetIncomeLoss	$ 107,911us-gaap_NetIncomeLoss
Investment gains:
Investment gains during the period	20,009	86,080
Income tax charge	7,205	30,570
Investments gains, net of tax	12,804	55,510
Less reclassification adjustments to:
Net realized investment gain	13,186	20,246
Income tax expense	4,615	7,086
Total reclassifications included in net earnings, net of tax	8,571	13,160
Net unrealized investment gains	4,233	42,350
Foreign currency translation adjustment	(7,052)	788
Income tax benefit	(67)	(432)
Foreign currency translation adjustment, net of tax	(6,985)	1,220
Other comprehensive income (loss)	(2,752)	43,570
Comprehensive income	$ 110,165us-gaap_ComprehensiveIncomeNetOfTax	$ 151,481us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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