Receivable from and Payable to Brokers, Dealers and Clearing Organizations - Schedule of Receivable from and Payable to Brokers, Dealers and Clearing Organization (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Receivable from brokers, dealers and clearing organizations consist of:
Securities borrowed	$ 158,454	$ 154,090
Receivable from brokers	25,095	25,768
Securities failed to deliver	15,147	6,172
Clearing organizations	22,700	26,081
Other	3,310	2,823
Receivables from brokers, dealers and clearing organizations	224,706	214,934
Payable to brokers, dealers and clearing organizations consist of:
Securities loaned	141,654	179,875
Payable to brokers	17,976	610
Securities failed to receive	34,421	11,523
Other	45,527	29,381
Payable to brokers, dealers and clearing organizations	$ 239,578	$ 221,389