Securities - Investments in Pooled Trust Preferred Securities (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Investments in pooled trust preferred securities
Amortized Cost	$ 1,254,258	$ 1,264,529
Fair Value	1,268,280	1,250,777
Unrealized Loss	(4,441)	(18,269)
Trust preferred securities
Investments in pooled trust preferred securities
Amortized Cost	12,245	12,359
Fair Value	10,386	$ 10,633
Unrealized Loss	(1,859)
XXIII
Investments in pooled trust preferred securities
Amortized Cost	8,199
Fair Value	6,693
Unrealized Loss	$ (1,506)
Issuers Currently in Deferral or Default	15.00%
XXVI
Investments in pooled trust preferred securities
Amortized Cost	$ 4,046
Fair Value	3,693
Unrealized Loss	$ (353)
Issuers Currently in Deferral or Default	18.00%

Percentage of issuers currently in deferral or default.

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- Definition

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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