Schedule III-Supplementary Insurance Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule III-Supplementary Insurance Information
Deferred acquisition costs	$ 26,435	$ 24,521	$ 20,600
Future policy benefits and expenses	2,906,706	2,743,876	2,804,648
Unearned premiums	34,355	30,535	30,021
Claims and benefits payable	1,717,938	1,679,730	1,695,090
Premium revenues	1,035,467	1,001,631	1,007,986
Net investment income	180,734	182,960	198,728
Benefits claims, losses and settlement expenses	746,101	745,247	731,862
Amortization of deferred policy acquisition costs	31,212	28,438	27,030
Other operating expenses	$ 357,839	$ 349,782	$ 348,020

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

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

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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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