Investment Securities - Components of Investment Securities Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Available for sale securities:
Gains realized on sales	$ 6	$ 47	$ 6	$ 253
Losses realized on sales	(46)	0	(46)
Other-than-temporary impairment recognized	0	0
Other investment securities:
Fair value adjustments, net	0	3		3
Investment securities (losses) gains, net	(40)	50	(40)	256
Proceeds from sale of U S treasury securities	$ 21,500	$ 25,400	$ 21,503	$ 77,168

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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