1. Summary of significant accounting policies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings available to common stockholders:
Net income	$ 2,094	$ 1,897
Minority interest	4	26
Preferred stock dividends	128	128
Net income available to common stockholders	$ 1,962	$ 1,743