Investments and Derivative Instruments (Details Textual 4) (USD $) In Billions, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2012 percent	Dec. 31, 2011
Concentration Risk [Line Items]
Concentration Risk, Benchmark Description	greater than 10% of the Company’s stockholder’s equity	greater than 10% of the Company’s stockholder’s equity
hig_CompanysLargestExposureToConcentrationOfCreditRiskWithASingleIssuer	$ 1.1
hig_CompanysPercentageOfLargestExposureToStockholdersEquity	0.00%
hig_CompanysPercentageOfLargestExposureToInvestedAssets	0.00%

Identifies or describes the benchmark that serves as the denominator in the calculation of the percentage of concentration risk.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13537-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13531-108611

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