Securities - Investments in Pooled Trust Preferred Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Investments in pooled trust preferred securities
Amortized Cost	$ 1,276,871	$ 1,264,529
Fair Value	1,290,613	1,250,777
Gross Unrealized Losses	(4,878)	(18,269)
Trust preferred securities
Investments in pooled trust preferred securities
Amortized Cost	12,153	12,359
Fair Value	9,986	$ 10,633
Gross Unrealized Losses	(2,167)
XXIII
Investments in pooled trust preferred securities
Amortized Cost	8,182
Fair Value	6,410
Gross Unrealized Losses	$ (1,772)
Issuers currently in deferral or default (percent)	15.00%
XXVI
Investments in pooled trust preferred securities
Amortized Cost	$ 3,971
Fair Value	3,576
Gross Unrealized Losses	$ (395)
Issuers currently in deferral or default (percent)	19.00%

Percentage of issuers currently in deferral or default.

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of 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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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