Fair Value of Assets and Liabilities (Details 2) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016 USD ($) Security	Mar. 31, 2015 USD ($) Security	Dec. 31, 2015 USD ($) Security	Dec. 31, 2014 USD ($)
Breakdown of trust preferred securities
Number considered OTTI | Security	1	1
Life-to-date impairment recognized in earnings	$ 140	$ 140	$ 140	$ 140
Trust preferred securities
Breakdown of trust preferred securities
Total number of trust preferred securities | Security	2		2
Par value, trust preferred securities	$ 1,776		$ 1,780
Number not considered OTTI | Security	1		1
Par value, trust preferred securities not considered OTTI	$ 776		$ 780
Number considered OTTI | Security	1		1
Par value, trust preferred securities considered OTTI	$ 1,000		$ 1,000
Life-to-date impairment recognized in earnings	140	$ 140	140	$ 140
Life-to-date impairment recognized in other comprehensive income	910		862
Total life-to-date impairment	$ 1,050		$ 1,002