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Contingencies - Additional Information (Detail) (USD $) | 6 Months Ended
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Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract] |
Minimum estimated range of aggregate loss for legal proceedings | $ 0
Maximum estimated range of aggregate loss for legal proceedings | 30,000,000
Total amount of ARS the firm purchased and hold | 99,400,000
Amount of ARS committed to purchase from clients | 20,200,000
Eligible investor subject to future buyback potential additional losses related to valuation adjustments | $ 110,600,000
Period of auction rates security to be purchased from rendering of the award | 30 days

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- Definition The total amount of ARS the firm purchased and hold. + References No definition available. + Details
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X
- Definition The amount of ARS the firm committed to purchase from clients. + References No definition available. + Details
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- Definition Eligible investor subject to future buyback potential additional losses related to valuation adjustments. + References No definition available. + Details
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- Definition Period of auction rates security to be purchased from rendering of award. + References No definition available. + Details
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- Details
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- Definition The estimated maximum amount of possible loss from the contingency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 + Details
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- Definition The estimated minimum amount of possible loss from the contingency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 + Details
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