Investment Securities - Schedule of Amortized Cost and Fair Value by Contractual Maturity of Debt Securities (Details) - Municipal securities $ in Thousands	Jun. 30, 2017 USD ($)
Schedule Of Debt Securities [Line Items]
Within 1 year, amortized cost	$ 2,824
1-5 years, amortized cost	13,930
5-10 years, amortized cost	1,490
Amortized Cost	18,244
Within 1 year, fair value	2,823
1-5 years, fair value	14,046
5-10 years, fair value	1,478
Fair Value	$ 18,347
Within 1 year, weighted average yield	0.96%
1-5 years, weighted average yield	2.27%
5-10 years, weighted average yield	4.78%
Weighted Average Yield	2.27%