Investment Securities - Gross unrealized losses and fair value, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position (Details 2) $ in Thousands		Mar. 31, 2017 USD ($) Securities Security	Dec. 31, 2016 USD ($) Securities Security
Available-for-Sale
Less than Twelve Months Number of individual securities | Security		10	9
Less than Twelve Months, unrealized losses		$ 133	$ 159
Less than Twelve Months, fair value		$ 12,036	$ 11,437
Twelve Months or More Number of individual securities | Security		2	2
Twelve Months or More, unrealized losses		$ 14	$ 14
Twelve Months or More, fair value		$ 929	$ 987
Total Number of Individual Securities | Security		12	11
Total Unrealized Losses		$ 147	$ 173
Total Fair Value		$ 12,965	$ 12,424
Held-to-Maturity
Less than Twelve Months Number of individual securities | Securities		13	15
Less than Twelve Months, Unrealized Losses		$ 41	$ 74
Less than Twelve Months, Fair Value		$ 3,474	$ 4,453
Twelve Months or More Number of individual securities | Securities		1	1
Twelve Months or More, Unrealized Losses
Twelve Months or More, Fair Value		$ 45	$ 45
Total Number of Individual Securities | Securities		14	16
Total Unrealized Losses		$ 41	$ 74
Total Fair Value		$ 3,519	$ 4,498
U.S. Government and agency obligations
Available-for-Sale
Less than Twelve Months Number of individual securities | Security		7	6
Less than Twelve Months, unrealized losses		$ 99	$ 110
Less than Twelve Months, fair value		$ 8,007	$ 6,996
Twelve Months or More Number of individual securities | Security
Twelve Months or More, unrealized losses
Twelve Months or More, fair value
Total Number of Individual Securities | Security		7	6
Total Unrealized Losses		$ 99	$ 110
Total Fair Value		$ 8,007	$ 6,996
Mortgage-backed securities - residential
Available-for-Sale
Less than Twelve Months Number of individual securities | Security		3	3
Less than Twelve Months, unrealized losses		$ 34	$ 49
Less than Twelve Months, fair value		$ 4,029	$ 4,441
Twelve Months or More Number of individual securities | Security		2	2
Twelve Months or More, unrealized losses		$ 14	$ 14
Twelve Months or More, fair value		$ 929	$ 987
Total Number of Individual Securities | Security		5	5
Total Unrealized Losses		$ 48	$ 63
Total Fair Value		$ 4,958	$ 5,428
Held-to-Maturity
Less than Twelve Months Number of individual securities | Securities	[1]	1	1
Less than Twelve Months, Unrealized Losses	[1]
Less than Twelve Months, Fair Value	[1]	$ 177	$ 178
Twelve Months or More Number of individual securities | Securities	[1]
Twelve Months or More, Unrealized Losses	[1]
Twelve Months or More, Fair Value	[1]
Total Number of Individual Securities | Securities	[1]	1	1
Total Unrealized Losses	[1]
Total Fair Value	[1]	$ 177	$ 178
State and Municipal securities
Held-to-Maturity
Less than Twelve Months Number of individual securities | Securities	[1]	12	14
Less than Twelve Months, Unrealized Losses	[1]	$ 41	$ 74
Less than Twelve Months, Fair Value	[1]	$ 3,297	$ 4,275
Twelve Months or More Number of individual securities | Securities	[1]	1	1
Twelve Months or More, Unrealized Losses	[1]
Twelve Months or More, Fair Value	[1]	$ 45	$ 45
Total Number of Individual Securities | Securities	[1]	13	15
Total Unrealized Losses	[1]	$ 41	$ 74
Total Fair Value	[1]	$ 3,342	$ 4,320

[1] Aggregate unrealized loss position of these securities is less than $500.