v2.4.0.8

Significant Accounting Policies (Details) (USD $) | 6 Months Ended |  |
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Jun. 30, 2014 | Dec. 31, 2013 | May 03, 2007
Significant Accounting Policies [Abstract] |  |  |
SIP expense - Year of grant |  |  | 50.00%
SIP expense - Remaining vesting period |  |  | 50.00%
SIP expense - Employees over 59 in year of grant |  |  | 100.00%
Percent of shares forfeited post employment |  |  | 50.00%
Over 59 percent of shares eligible |  |  | 100.00%
U.S. Treasury Bills | $ 3,430,000,000 | $ 1,300,000,000 |
Securities Purchased Under Agreement to Resell Segregated for Regulatory Purposes | 5,910,000,000 | 6,730,000,000 |
Equity method investments | 24,700,000 | 27,500,000 |
Cost method investments | $ 27,500,000 | $ 27,600,000 |
Property and equipment useful lives | Computer equipment is depreciated over three to five years and office furniture and equipment are depreciated over five to seven years. Qualifying costs for internally developed software are capitalized and amortized over the expected useful life of the developed software, not to exceed three years. |  |

X
- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock and member interests in limited liability companies and partnerships of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References No definition available. + Details
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- Definition Percentage of unvested shares to be received by employees over the age of 59 who discontinue employment with the Company without cause and continue to meet the terms of the plans' post-employment provisions. + References No definition available. + Details
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- Definition Percentage of unvested shares forfeited by employees who discontinue employment with the Company without cause and continue to meet the terms of the plans' post-employment provisions. + References No definition available. + Details
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- Definition The carrying value of funds, segregated for regulatory purposes and for the exclusive benefit of customers, outstanding loaned in the form of security resale agreements if the agreement requires the purchaser to resell the identical security purchased or a security that meets the definition of "substantially the same" in the case of a dollar roll. Also includes purchases of participations in pools of securities that are subject to a resale agreement. + References No definition available. + Details
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- Definition Percent of fair value of stock grant expensed during the first year of the grant for employees who are over fifty nine years old. + References No definition available. + Details
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- Definition Percent of fair value of stock grant expensed after the first year of the grant. + References No definition available. + Details
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- Definition Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments. + 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 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 20 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=29638308&loc=d3e40346-111594 + Details
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- Definition The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=29643736&loc=d3e42546-110969 + Details
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- Definition Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2155824 + Details
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