7. Commitments and contingencies (Details) - USD ($)	3 Months Ended
	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Litigation Settlement, Amount		$ 3,600,000
Loss Contingency, Settlement Agreement, Terms		$25,000
Estimated Litigation Liability, Current		$ 3,625,000	$ 3,625,000
Loss Contingency Accrual, Provision	$ 25,000