Defined Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 5,230		$ 5,639		$ 5,791
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Defined Benefit Plan, Benefit Obligation	5,591		6,311
Service cost	53		50		54
Interest cost	216		264		317
Defined Benefit Plan, Actuarial Gain (Loss)	(50)		(55)
Defined Benefit Plan, Curtailments	(98)		0
Defined Benefit Plan, Settlements, Benefit Obligation	(1,269)		(991)
Defined Benefit Plan, Foreign Currency Exchange Rate Gain (Loss)	(7)		12
Defined Benefit Plan, Benefit Obligation	4,436		5,591		6,311
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	5,639		5,791
Defined Benefit Plan, Actual Return on Plan Assets	676		206
Defined Benefit Plan, Contributions by Employer	0		633
Defined Benefit Plan, Benefits Paid	(1,085)		(991)
Defined Benefit Plan, Fair Value of Plan Assets	5,230		5,639		5,791
Defined Benefit Plan, Funded Status of Plan	794		48
Pension and Other Postretirement Defined Benefit Plans, Liabilities [Abstract]
Pension and Other Postretirement Defined Benefit Plans, Liabilities	794		48
Defined Benefit Plan, Accumulated Benefit Obligation	4,436		5,533
Components of net periodic benefit cost included in employee compensation and benefits
Service cost	53		50		54
Interest cost	216		264		317
Expected return on plan assets	(235)		(276)		(294)
Amortization of (loss) / gain	0		0		0
Amortization of prior service cost	20		21		21
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments	(59)		0		(10)
Defined Benefit Plan, Special Termination Benefits	6		0		0
Effect of settlement	(95)		(29)		(5)
Net periodic benefit cost	(94)		30		83
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Gain (Loss), before Tax	(557)
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Effect of Curtailment, before Tax	59
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Effect of Settlement, before Tax	98
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Amortization of Loss (Gain), before Tax	0
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Prior Service Cost, before Tax	(23)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	(423)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	479
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax	(381)
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Transition Assets (Obligations), before Tax	0
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	98
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Defined Benefit Plan, Amortization of Net Prior Service Cost (Credit)	19		19		3
Defined Benefit Plan, Amortization of Net Gains (Losses)	0		0		0
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	2,016
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	360
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	2,260
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	274
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	2,111
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	4,546
Defined Benefit Plan, Expected Future Benefit Payments	11,567
Cash Balance Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	5,230		5,639
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	5,639
Defined Benefit Plan, Fair Value of Plan Assets	5,230		5,639
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets	6.00%		6.00%		6.00%
Cash Balance Plan [Member] | Ramius Multi-Strategy Fund Ltd [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	513	[1]	506	[1]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	513	[1]	506	[1]
Cash Balance Plan [Member] | Ramius Global Credit Fund Ltd [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	1,304	[2]	1,040	[2]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	1,304	[2]	1,040	[2]
Cash Balance Plan [Member] | External Mutual Funds Total Return [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	1,358	[3]	1,785	[3]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	1,358	[3]	1,785	[3]
Cash Balance Plan [Member] | External Mutual Funds Real Return [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	1,019	[4]	1,079	[4]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	1,019	[4]	1,079	[4]
Cash Balance Plan [Member] | External Mutual Funds Conservative [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	1,036	[5]	1,229	[5]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Defined Benefit Plan, Fair Value of Plan Assets	$ 1,036	[5]	$ 1,229	[5]

[1] Ramius Multi-Strategy Fund Ltd invests substantially all of its capital through a "master feeder" structure in Ramius Intermediate Fund, L.P. which invests in funds that employ a variety of diversified, non-directional investment strategies that seek to achieve, over the long term, a target return with low volatility.

[2] Ramius Global Credit Fund Ltd invests substantially all of its capital through a "master-feeder" structure in Ramius Global Credit Intermediate Fund, LP which invests in a fund whose objective is to seek to achieve superior returns.

[3] External Mutual Funds—Total Return's main objective is to achieve maximum total return by investing assets in a diversified portfolio of fixed income instruments of varying maturities which may be represented by derivatives.

[4] External Mutual Funds—Real Return's main objective is to seek to achieve maximum total return after inflation consistent with preservation of real capital and prudent investment management.

[5] External Mutual Funds—Conservative's main objective is to seek to achieve a high level of current income with some consideration given to the growth of capital by investing in fixed-income securities.