Stock-based expense and assumptions (Tables)

3 Months Ended

Mar. 31, 2013

Stock-based expense and assumptions

Summary of stock-based expense recognized by income statement classification

	Three months ended March 31,
	2013		2012
Processing and service costs	$	49,643	$	80,781
Selling, general and administrative expenses	209,286		143,611
Total stock-based expense	$	258,929	$	224,392