Securities (Securities in a Continuous Unrealized Loss Position) (Details) $ in Thousands	Sep. 30, 2021 USD ($) security	Dec. 31, 2020 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, number of securities \| security	50	22
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, fair value	$ 673,749	$ 171,139
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, unrealized losses	$ 10,971	$ 672
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, number of securities \| security	20	8
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, fair value	$ 68,289	$ 22,597
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, unrealized losses	$ 1,841	$ 1,897
Available for sale debt securities, securities in continuous unrealized loss position, number of securities \| security	70	30
Available for sale debt securities, securities in continuous unrealized loss position, fair value	$ 742,038	$ 193,736
Available for sale debt securities, securities in continuous unrealized loss position, unrealized losses	$ 12,812	$ 2,569
Obligations of U.S. government-sponsored enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, number of securities \| security	14	6
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, fair value	$ 167,238	$ 63,856
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, unrealized losses	$ 2,499	$ 145
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, number of securities \| security	1	0
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, fair value	$ 497	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, unrealized losses	$ 3	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, number of securities \| security	15	6
Available for sale debt securities, securities in continuous unrealized loss position, fair value	$ 167,735	$ 63,856
Available for sale debt securities, securities in continuous unrealized loss position, unrealized losses	$ 2,502	$ 145
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, number of securities \| security	36	16
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, fair value	$ 506,511	$ 107,283
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, unrealized losses	$ 8,472	$ 527
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, number of securities \| security	12	0
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, fair value	$ 46,265	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, unrealized losses	$ 843	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, number of securities \| security	48	16
Available for sale debt securities, securities in continuous unrealized loss position, fair value	$ 552,776	$ 107,283
Available for sale debt securities, securities in continuous unrealized loss position, unrealized losses	$ 9,315	$ 527
Individual name issuer trust preferred debt securities
Debt Securities, Available-for-sale [Line Items]
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, number of securities \| security	0	0
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, fair value	$ 0	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, unrealized losses	$ 0	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, number of securities \| security	3	5
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, fair value	$ 9,157	$ 12,669
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, unrealized losses	$ 213	$ 672
Available for sale debt securities, securities in continuous unrealized loss position, number of securities \| security	3	5
Available for sale debt securities, securities in continuous unrealized loss position, fair value	$ 9,157	$ 12,669
Available for sale debt securities, securities in continuous unrealized loss position, unrealized losses	$ 213	$ 672
Corporate bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, number of securities \| security	0	0
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, fair value	$ 0	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, less than 12 months, unrealized losses	$ 0	$ 0
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, number of securities \| security	4	3
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, fair value	$ 12,370	$ 9,928
Available for sale debt securities, securities in continuous unrealized loss position, greater than 12 months, unrealized losses	$ 782	$ 1,225
Available for sale debt securities, securities in continuous unrealized loss position, number of securities \| security	4	3
Available for sale debt securities, securities in continuous unrealized loss position, fair value	$ 12,370	$ 9,928
Available for sale debt securities, securities in continuous unrealized loss position, unrealized losses	$ 782	$ 1,225

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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