Schedule IV - Reinsurance (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reinsurance Premiums And Life Insurance In force For Insurance Companies By Product Segment Line Items
Life Insurance in Force, gross amount	$ 154,488,511	$ 150,107,614	$ 144,778,793
Life Insurance in Force, ceded to other companies	782,125	800,905	738,935
Life Insurance in Force, assumed from other companies	3,882,237	4,138,180	4,414,247
Life Insurance in Force, Net Amount	157,588,623	153,444,889	148,454,105
Life Insurance in Force, percentage of amount assumed to net	2.50%	2.70%	3.00%
Premium, gross amount	3,010,959	2,812,248	2,607,058
Premium, ceded to other companies	7,769	9,821	7,001
Premium, assumed from other companies	26,960	30,725	31,311
Premium income	3,030,150	2,833,152	2,631,368
Percentage of assumed premiums earned to net premiums earned	0.90%	1.10%	1.20%
Life Insurance [Member]
Reinsurance Premiums And Life Insurance In force For Insurance Companies By Product Segment Line Items
Premium, gross amount	1,841,425	1,762,640	1,675,307
Premium, ceded to other companies	4,645	7,592	4,716
Premium, assumed from other companies	26,960	30,725	31,311
Premium income	1,863,740	1,785,773	1,701,902
Percentage of assumed premiums earned to net premiums earned	1.40%	1.70%	1.80%
Health Insurance [Member]
Reinsurance Premiums And Life Insurance In force For Insurance Companies By Product Segment Line Items
Premium, gross amount	1,169,534	1,049,608	931,751
Premium, ceded to other companies	3,124	2,229	2,285
Premium, assumed from other companies	0	0	0
Premium income	$ 1,166,410	$ 1,047,379	$ 929,466
Percentage of assumed premiums earned to net premiums earned	0.00%	0.00%	0.00%