Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	$ 13,918	$ 41,201
Less than 12 months, unrealized losses	66	507
More than 12 months, fair value	68,044	137,480
More than 12 months, unrealized losses	133	1,455
Fair Value	81,962	178,681
Unrealized Losses	199	1,962
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	0	5,030
Less than 12 months, unrealized losses	0	6
More than 12 months, fair value	67,393	135,807
More than 12 months, unrealized losses	117	1,433
Fair Value	67,393	140,837
Unrealized Losses	117	1,439
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	2,982	22,285
Less than 12 months, unrealized losses	12	397
More than 12 months, fair value	0	0
More than 12 months, unrealized losses	0	0
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	10,936	13,886
Less than 12 months, unrealized losses	54	104
More than 12 months, fair value	0	0
More than 12 months, unrealized losses	0	0
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	0	0
Less than 12 months, unrealized losses	0	0
More than 12 months, fair value	651	1,673
More than 12 months, unrealized losses	16	22
Fair Value	651	1,673
Unrealized Losses	$ 16	$ 22

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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