Deferred Policy Acquisition Costs (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2010
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Balance, beginning of year	$ 194,466	$ 185,910		$ 171,430
Policy acquisition costs deferred	528,944	514,073	492,268
Amortization	(526,208)	(505,517)	(477,788)
Balance, end of year	$ 197,202	$ 194,466	$ 185,910	$ 171,430

Additions during the period in (a) capitalized policy acquisition costs, and (b) capitalized present value of future profits (also known as PVFP).

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- Definition

Amount of deferred policy acquisition costs and capitalized present value of the future profits (PVFP) expensed. Acquisition costs are costs that are related directly to the successful acquisition of new or renewal insurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section S99

-Paragraph 2

-Subparagraph (2)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 30

-Section 50

-Paragraph 1

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- Definition

Carrying (unamortized) amount as of the balance sheet date of deferred policy acquisition costs and value of business acquired (also called present value of future profits).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.7)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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