Securities - Investments in Pooled Trust Preferred Securities (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Investments in pooled trust preferred securities
Amortized Cost	$ 1,222,123	$ 1,264,529
Fair Value	1,238,577	1,250,777
Unrealized Loss	(4,137)	(18,269)
Trust preferred securities
Investments in pooled trust preferred securities
Amortized Cost	12,160	12,359
Fair Value	9,862	$ 10,633
Unrealized Loss	(2,298)
XXIII
Investments in pooled trust preferred securities
Amortized Cost	8,174
Fair Value	6,360
Unrealized Loss	$ (1,814)
Issuers Currently in Deferral or Default	16.00%
XXVI
Investments in pooled trust preferred securities
Amortized Cost	$ 3,986
Fair Value	3,502
Unrealized Loss	$ (484)
Issuers Currently in Deferral or Default	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).

+ References

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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