Related Party Transactions (Details) (USD $)			0 Months Ended	3 Months Ended	12 Months Ended					0 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Nov. 07, 2012 RangeMark item	Mar. 31, 2013 Former stockholders of Gleacher Partners, Inc.	Dec. 31, 2012 Former stockholders of Gleacher Partners, Inc.	Dec. 31, 2011 Former stockholders of Gleacher Partners, Inc.	Dec. 31, 2010 Former stockholders of Gleacher Partners, Inc.	Mar. 31, 2013 Former owners of RangeMark	Dec. 31, 2012 Former owners of RangeMark	Nov. 07, 2012 Former owners of RangeMark RangeMark item
Related Party Transactions
Aggregate purchase consideration			$ 2,500,000							$ 2,500,000
Number of installments in which purchase consideration is payable			4							4
Amount agreed to be paid to selling parties				10,000,000
Period over which purchase consideration will be paid to selling parties				5 years
Payment of purchase consideration obligation					4,400,000	0	4,900,000
Amounts receivable from or payable to related parties
Receivables from related parties	1,474,000	1,474,000		1,474,000	1,474,000
Payables to related parties	2,984,000	2,944,000		594,000	594,000			2,390,000	2,350,000
Present value of remaining obligation				$ 2,500,000