Investment Securities - Gains and (Losses) Recognized in Earnings (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($) security	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) security	Jun. 30, 2018 USD ($)
Investments, Debt and Equity Securities [Abstract]
Securities in unrealized loss positions, qualitative disclosure, number of positions (in security) \| security	512		512
Proceeds	$ 133,829	$ 4,215	$ 205,331	$ 4,215
Gross gains	4,180	42	4,732	42
Gross losses	$ (20)	$ (39)	$ (485)	$ (39)

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

No definition available.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
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-Publisher FASB
-Name Accounting Standards Codification
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