Schedule III - Supplementary Insurance Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplementary Insurance Information [Abstract]
Deferred policy acquisition costs	$ 2,058,556	$ 2,426,652	$ 1,709,799
Future policy benefits, losses, claims and loss expenses	39,802,861	35,789,655	31,773,988
Unearned premiums	0	0	0
Other policy claims and benefits payable	365,819	418,033	455,752
Premium revenue	151,613	148,938	165,681
Net investment income	1,531,667	1,383,927	1,286,923
Benefits, claims, losses and settlement expenses	1,679,255	1,713,019	1,264,016
Amortization of deferred policy acquisition costs	163,578	365,468	164,919
Other operating expenses	$ 130,076	$ 142,873	$ 137,432

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Amount of amortization of deferred policy acquisition costs recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 235

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-16)

-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915

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Amount of insurance benefits, claims, losses and settlement expenses incurred.

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- Definition

Net amount of deferred policy acquisition costs capitalized on contracts remaining in force on the balance sheet date.

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- Definition

Amount of reserves for future policy claims payable and loss expenses to be incurred.

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- Definition

Amount of net investment income earned.

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Amount of other operating expense incurred.

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Amount of claims and benefits payable not included within other categories.

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Amount of premium revenue earned.

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Amount of premiums not yet earned.

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