This item contains disclosure of the number of investment positions in the available-for-sale investments that have been determined to be other than temporarily impaired (both credit and non-credit).

No definition available.

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560

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- Definition

Amount before tax of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34D

-URI http://asc.fasb.org/extlink&oid=27723805&loc=SL6284304-111560

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 35

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25362-111560

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8B

-URI http://asc.fasb.org/extlink&oid=27724398&loc=SL6284393-111563

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Summary of Activity Related to Other-Than-Temporary Impairment Losses (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended					12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2014 Investment	Dec. 31, 2013 Investment	Dec. 31, 2012 Investment
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of Securities						31	4	4
Total other-than-temporary impairment losses	$ 21us-gaap_ImpairmentOfInvestments	$ (158)us-gaap_ImpairmentOfInvestments	$ 530us-gaap_ImpairmentOfInvestments	$ 1,821us-gaap_ImpairmentOfInvestments	$ 42us-gaap_ImpairmentOfInvestments	$ (137)us-gaap_ImpairmentOfInvestments	$ 2,393us-gaap_ImpairmentOfInvestments	$ 902us-gaap_ImpairmentOfInvestments
Portion of loss recognized in other comprehensive income	21	(158)				(137)		44
Net other-than-temporary impairment losses recognized in earnings			530	1,821	42		2,393	858
Corporate And Other Bonds
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of Securities							1
Total other-than-temporary impairment losses							1,822
Net other-than-temporary impairment losses recognized in earnings							1,822
Residential Mortgage Backed Securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of Securities						31		1
Total other-than-temporary impairment losses						(137)		55
Portion of loss recognized in other comprehensive income						(137)		44
Net other-than-temporary impairment losses recognized in earnings								11
Equity Securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of Securities							3	3
Total other-than-temporary impairment losses							571	847
Net other-than-temporary impairment losses recognized in earnings							$ 571	$ 847