Segment and Geographic Information - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2013 Segment	Mar. 31, 2012 Segment	Jun. 30, 2012 Segment	Dec. 31, 2012 Segment	Dec. 31, 2013 Segment	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Number of reportable segments prior to acquisitions			1
Number of reportable segments	2	1	2	2	2
Other revenues					$ 44,643,000	$ 4,495,000	$ 4,174,000
Collection of receivables and associated expenses					10,600,000	21,100,000	3,800,000
Gain on divestiture					723,147,000
Sale of eSpeed [Member]
Segment Reporting Information [Line Items]
Other revenues					39,500,000
Gain on divestiture					723,100,000
Sale of eSpeed [Member] | Global Partnership Restructuring Program [Member]
Segment Reporting Information [Line Items]
Compensation expense					$ 465,000,000