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Securities (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2021 USD ($) security | Dec. 31, 2020 USD ($) security | Dec. 31, 2019 USD ($)
Unrealized loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 431 | 104 |
OTTI credit loss recognized | $ |  |  | $ 0
Provision for credit losses recognized | $ | $ 0 | $ 0 |
Collateralized loan obligations (“CLOs”) |  |  |
Unrealized loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position |  | 3 |
Mortgage backed securities issued by us government agencies and government sponsored enterprise |  |  |
Unrealized loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 180 | 46 |
U.S. government agency and U.S. government-sponsored enterprise debt securities |  |  |
Unrealized loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 50 |  |
U.S. Treasury securities |  |  |
Unrealized loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 21 |  |
Corporate debt securities |  |  |
Unrealized loss |  |  |
Number of available-for-sale debt securities in an unrealized loss position | 30 | 17 |

X
- Definition Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82922868-210454 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922897-210455 + Details
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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455 + Details
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- Definition This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123581744&loc=SL6284393-111563 + Details
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