Accrued expenses and other liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Accrued expenses and other liabilities
Revenue share	$ 4,383	$ 4,598
Salaries and wages	2,654	3,024
Accrued for construction-in-progress	3,626	2,717
Accrued partner network	535	736
Deferred rent	847	853
Holdback liabilities	1,600	1,875
Contingent consideration	1,564	980
Other	2,700	2,125
Total accrued expenses and other liabilities	$ 17,909	$ 16,908