Income Taxes Summary of Operating Loss Carryforwards (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Other	$ 2,394,000us-gaap_DeferredTaxAssetsOther	$ 4,081,000us-gaap_DeferredTaxAssetsOther
Valuation Allowance, Amount	2,263,000	148,816,000
Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	230,000,000
Operating Loss Carryforwards, Expiration Dates	Dec. 31, 2033
The New York State [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	295,000,000
Operating Loss Carryforwards, Expiration Dates	Dec. 31, 2033
Hong Kong Inland Revenue Department [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	14,000,000
Luxembourg Reinsurance Companies [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Other	183,400,000
Deferred Tax Liabilities, Gross, Current	204,200,000
Valuation Allowance, Amount	183,400,000
LaBranche and Co Inc. [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	64,000,000
Deferred tax asset, deduction limitation	$ 6,700,000

Deferred tax asset, deduction limitation

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed within one year or operating cycle, if longer.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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