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Fair Value Measurements - Summary of Changes in Fair Value of Assets Measured at Fair Value (Detail) (Fair Value, Inputs, Level 3 [Member], USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2014 | Dec. 31, 2013
Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Measurements Disclosure [Line Items] |  |
Beginning balance | $ 10,591 |
Purchases |  | 10,000
Total gains unrealized (Included in earnings as part of net investment income) | 229 | 591
Ending Balance | $ 10,820 | $ 10,591

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- Definition Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss Included In Earnings + References No definition available. + Details
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- Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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