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Investment in Life Settlements - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended |  | 9 Months Ended |  |
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Sep. 30, 2012 Contract | Sep. 30, 2011 | Sep. 30, 2012 Contract | Sep. 30, 2011 | Dec. 31, 2011 | Sep. 30, 2012 Lsc Entities | Sep. 30, 2011 Lsc Entities | Sep. 30, 2012 Tiger Contract | Sep. 30, 2012 ACAC | Aug. 31, 2011 ACAC
Schedule of Cost-method Investments [Line Items] |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest |  |  |  |  |  |  |  |  | 21.25% | 21.25%
Profits and losses of investment in life insurance policies and premium finance loans |  |  | 60.625% |  |  |  |  |  |  |
Life insurance policies acquired |  |  | $ 14,021 | $ 19,965 |  | $ 28,042 | $ 39,930 |  |  |
Investments in life settlements and cash value loans | 173,298 |  | 173,298 |  | 136,800 |  |  |  |  |
Other income related to life insurance policies | 3,251 | 6,882 | 5,302 | 48,346 |  |  |  |  |  |
Number of life settlement contracts | 256 |  | 256 |  |  |  |  |  |  |
Number of premium finance loans |  |  |  |  |  |  |  | 14 |  |
Value of premium finance loans |  |  |  |  |  |  |  | 1,822 |  |
Face value of life settlement contracts | 1,671,013 |  | 1,671,013 |  |  |  |  |  |  |
Face value of premium finance loans |  |  |  |  |  |  |  | $ 68,250 |  |

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- Definition Other income from Life Insurance Policies + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Technical Bulletin (FTB) -Number 85-4 -Paragraph 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 4 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6812-107765 + Details
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- Definition Life insurance assumed from another insurer divided by gross life insurance in force. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 17 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 05 -Paragraph c -Article 7 + Details
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- Definition Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Life Settlement Contract -URI http://asc.fasb.org/extlink&oid=6516907 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 30 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6385267&loc=d3e42732-111610 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FTB85-4-1 -Paragraph 17 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Number of life settlement contracts accounted for under the fair value method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Life Settlement Contract -URI http://asc.fasb.org/extlink&oid=6516907 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 30 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6385267&loc=d3e42732-111610 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FTB85-4-1 -Paragraph 17 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The cash outflow for payments to purchase life insurance policies for which the entity is the beneficiary. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3213-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15, 17 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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