Investment Securities - Summary of Carrying Amounts and Estimated Fair Values of Securities Held-to-Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule Of Held To Maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	$ 61,437	$ 65,882
Held-to-maturity, Gross Unrealized Gains	627	243
Held-to-maturity, Gross Unrealized Losses, Less Than 12 Months	(9)	(74)
Held-to-maturity, Gross Unrealized Losses, 12 Months or Longer	(5)	(2)
Held-to-maturity, Fair Value	62,050	66,049
Municipal Securities
Schedule Of Held To Maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	59,205	63,650
Held-to-maturity, Gross Unrealized Gains	623	238
Held-to-maturity, Gross Unrealized Losses, Less Than 12 Months	(9)	(74)
Held-to-maturity, Gross Unrealized Losses, 12 Months or Longer	(5)	(2)
Held-to-maturity, Fair Value	59,814	63,812
Certificates of Deposit
Schedule Of Held To Maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	2,232	2,232
Held-to-maturity, Gross Unrealized Gains	4	5
Held-to-maturity, Fair Value	$ 2,236	$ 2,237