Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	$ 44,871	$ 41,201
Less than 12 months, unrealized losses	82	507
More than 12 months, fair value	16,970	137,480
More than 12 months, unrealized losses	25	1,455
Fair Value	61,841	178,681
Unrealized Losses	107	1,962
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	24,943	5,030
Less than 12 months, unrealized losses	30	6
More than 12 months, fair value	16,970	135,807
More than 12 months, unrealized losses	25	1,433
Fair Value	41,913	140,837
Unrealized Losses	55	1,439
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	1,998	22,285
Less than 12 months, unrealized losses	2	397
More than 12 months, fair value	0	0
More than 12 months, unrealized losses	0	0
Fair Value	1,998	22,285
Unrealized Losses	2	397
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	17,930	13,886
Less than 12 months, unrealized losses	50	104
More than 12 months, fair value	0	0
More than 12 months, unrealized losses	0	0
Fair Value	17,930	13,886
Unrealized Losses	$ 50	104
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value		0
Less than 12 months, unrealized losses		0
More than 12 months, fair value		1,673
More than 12 months, unrealized losses		22
Fair Value		1,673
Unrealized Losses		$ 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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