Investments - Schedule of Amortized Cost and Estimated Fair Value of Investment Securities by Contractual Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Available-for-sale, Amortized cost
Available for sale securities, Amortized cost, Due in one year or less	$ 35,094
Available for sale securities, Amortized cost, Due after one year through five years	44,852
Available for sale securities, Amortized cost, Due after five years through ten years	13,912
Available for sale securities, Amortized cost, Due after ten years	36,450
Available for sale securities, Amortized cost, Amortized cost	130,308
Available-for-sale, Fair value
Available for sale securities, Estimated fair value, Due in one year or less	35,335
Available for sale securities, Estimated fair value, Due after one year through five years	45,715
Available for sale securities, Estimated fair value, Due after five years through ten years	14,306
Available for sale securities, Estimated fair value, Due after ten years	37,625
Fair value	132,981	$ 153,685
Held-to-maturity, Amortized cost
Held to maturity securities, Amortized cost, Due in one year or less	874
Held to maturity securities, Amortized cost, Due after one year through five years	23,497
Held to maturity securities, Amortized cost, Due after five years through ten years	2,575
Held to maturity securities, Amortized cost, Due after ten years	19,117
Held to maturity securities, Amortized cost, Mortgage-backed securities	319,978
Held-to-maturity Securities, Total	366,041	346,666
Held-to-maturity, Fair value
Held to maturity securities, Estimated fair value, Due in one year or less	872
Held to maturity securities, Estimated fair value, Due after one year through five years	23,194
Held to maturity securities, Estimated fair value, Due after five years through ten years	2,564
Held to maturity securities, Estimated fair value, Due after ten years	18,915
Held to maturity securities, Estimated fair value, Mortgage-backed securities	317,633
Fair value	$ 363,178	$ 345,576