Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	$ 1,051,661	$ 881,570
Available for sale debt securities unrealized gains	10,257	15,570
Available for sale debt securities unrealized losses	(9,341)	(2,569)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, at fair value	1,052,577	894,571
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	186,051	131,186
Available for sale debt securities unrealized gains	248	628
Available for sale debt securities unrealized losses	(2,044)	(145)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, at fair value	184,255	131,669
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	841,102	725,890
Available for sale debt securities unrealized gains	10,009	14,942
Available for sale debt securities unrealized losses	(6,075)	(527)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, at fair value	845,036	740,305
Individual name issuer trust preferred debt securities
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	11,360	13,341
Available for sale debt securities unrealized gains	0	0
Available for sale debt securities unrealized losses	(294)	(672)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, at fair value	11,066	12,669
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities, amortized cost	13,148	11,153
Available for sale debt securities unrealized gains	0	0
Available for sale debt securities unrealized losses	(928)	(1,225)
Available for sale debt securities, allowance for credit losses	0	0
Available for sale debt securities, at fair value	$ 12,220	$ 9,928

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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Amount of allowance for credit loss on 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
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (a)
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Line items for schedule of Available for Sale and Held to Maturty Securities.

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