Accounts Payable and Accrued Expenses - Reserve for Transaction Losses (Detail) - Reserve For Transaction Losses $ in Thousands	6 Months Ended
	Jun. 30, 2015 USD ($)
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 189
Additions to expense	6,249
Losses incurred, net of recoveries	(6,098)
Balance at End of Year	$ 340