Securities - Investments in Pooled Trust Preferred Securities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Investments in pooled trust preferred securities
Amortized Cost	$ 1,253,939	$ 1,264,529
Fair Value	1,255,353	1,250,777
Unrealized Loss	(8,943)	(18,269)
Trust preferred securities
Investments in pooled trust preferred securities
Amortized Cost	12,259	12,359
Fair Value	10,246	$ 10,633
Unrealized Loss	(2,013)
XXIII
Investments in pooled trust preferred securities
Amortized Cost	8,233
Fair Value	6,593
Unrealized Loss	$ (1,640)
Issuers Currently in Deferral or Default	17.00%
XXVI
Investments in pooled trust preferred securities
Amortized Cost	$ 4,026
Fair Value	3,653
Unrealized Loss	$ (373)
Issuers Currently in Deferral or Default	20.00%

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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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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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
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-Name Accounting Standards Codification
-Topic 320
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