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Securities Loaned - Additional Information (Detail) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
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Debt Instrument [Line Items] |  |
Securities loaned | $ 8,622 | $ 57,623
CF & Co [Member] |  |
Debt Instrument [Line Items] |  |
Securities loaned | $ 8,600 | 57,600
Stated interest rate | 2.18% |
CF & Co [Member] | Securities Financing Transaction, Fair Value [Member] |  |
Debt Instrument [Line Items] |  |
Securities loaned | $ 8,600 | $ 57,600
CF & Co [Member] | Minimum [Member] |  |
Debt Instrument [Line Items] |  |
Stated interest rate |  | 3.10%
CF & Co [Member] | Maximum [Member] |  |
Debt Instrument [Line Items] |  |
Stated interest rate |  | 3.25%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 405 -Section 55 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35710563&loc=d3e44140-110984 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729 + Details
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