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Investment Securities - Unrealized Loss Positions (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
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Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | $ 612,985 | $ 201,204
Greater than or equal to 12 continuous months | 44,628 | 0
Total Securities in a loss position | 657,613 | 201,204
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (42,663) | (2,867)
Greater than or equal to 12 continuous months | (3,280) | 0
Held-to-maturity, gross unrealized losses | (45,943) | (2,867)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 849,125 | 797,781
Available-for-sale, greater than 12 continuous months, fair value | 20,759 | 14,173
Available-for-sale, total securities in a loss position, fair value | 869,884 | 811,954
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (38,582) | (12,411)
Available-for-sale, greater than 12 continuous months, unrealized loss | (2,477) | (615)
Available-for-sale, total securities in a loss position, unrealized loss | (41,059) | (13,026)
Marketable Securities, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Marketable securities, less than 12 continuous months, fair value | 1,462,110 | 998,985
Marketable securities, greater than 12 continuous months, fair value | 65,387 | 14,173
Marketable securities, total securities in a loss position, fair value | 1,527,497 | 1,013,158
Marketable Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Marketable securities, less than 12 continuous months, unrealized loss | (81,245) | (15,278)
Marketable securities, greater than 12 continuous months, unrealized loss | (5,757) | (615)
Marketable securities, total securities in a loss position, unrealized loss | (87,002) | (15,893)
MBS pass-through securities issued by FHLMC, FNMA and GNMA |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | 299,200 | 76,619
Greater than or equal to 12 continuous months | 0 | 0
Total Securities in a loss position | 299,200 | 76,619
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (18,528) | (712)
Greater than or equal to 12 continuous months | 0 | 0
Held-to-maturity, gross unrealized losses | (18,528) | (712)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 108,982 | 263,474
Available-for-sale, greater than 12 continuous months, fair value | 0 | 0
Available-for-sale, total securities in a loss position, fair value | 108,982 | 263,474
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (5,486) | (2,784)
Available-for-sale, greater than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, total securities in a loss position, unrealized loss | (5,486) | (2,784)
CMOs issued by FHLMC |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | 165,101 | 54,811
Greater than or equal to 12 continuous months | 4,328 | 0
Total Securities in a loss position | 169,429 | 54,811
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (11,498) | (1,045)
Greater than or equal to 12 continuous months | (313) | 0
Held-to-maturity, gross unrealized losses | (11,811) | (1,045)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 359,856 | 226,175
Available-for-sale, greater than 12 continuous months, fair value | 4,107 | 4,415
Available-for-sale, total securities in a loss position, fair value | 363,963 | 230,590
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (14,357) | (4,677)
Available-for-sale, greater than 12 continuous months, unrealized loss | (399) | (152)
Available-for-sale, total securities in a loss position, unrealized loss | (14,756) | (4,829)
CMOs issued by FNMA |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | 25,350 |
Greater than or equal to 12 continuous months | 0 |
Total Securities in a loss position | 25,350 |
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (1,000) |
Greater than or equal to 12 continuous months | 0 |
Held-to-maturity, gross unrealized losses | (1,000) |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 40,170 | 37,348
Available-for-sale, greater than 12 continuous months, fair value | 0 | 0
Available-for-sale, total securities in a loss position, fair value | 40,170 | 37,348
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (2,258) | (611)
Available-for-sale, greater than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, total securities in a loss position, unrealized loss | (2,258) | (611)
CMOs issued by GNMA |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | 11,944 |
Greater than or equal to 12 continuous months | 0 |
Total Securities in a loss position | 11,944 |
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (431) |
Greater than or equal to 12 continuous months | 0 |
Held-to-maturity, gross unrealized losses | (431) |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 37,732 | 44,790
Available-for-sale, greater than 12 continuous months, fair value | 0 | 0
Available-for-sale, total securities in a loss position, fair value | 37,732 | 44,790
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (1,725) | (553)
Available-for-sale, greater than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, total securities in a loss position, unrealized loss | (1,725) | (553)
SBA-backed securities |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | 3,216 |
Greater than or equal to 12 continuous months | 0 |
Total Securities in a loss position | 3,216 |
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (29) |
Greater than or equal to 12 continuous months | 0 |
Held-to-maturity, gross unrealized losses | (29) |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 43,665 | 7,478
Available-for-sale, greater than 12 continuous months, fair value | 1,124 | 1,209
Available-for-sale, total securities in a loss position, fair value | 44,789 | 8,687
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (1,400) | (112)
Available-for-sale, greater than 12 continuous months, unrealized loss | (44) | (43)
Available-for-sale, total securities in a loss position, unrealized loss | (1,444) | (155)
Debentures of government- sponsored agencies |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | 65,826 | 50,571
Greater than or equal to 12 continuous months | 40,300 | 0
Total Securities in a loss position | 106,126 | 50,571
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (6,510) | (901)
Greater than or equal to 12 continuous months | (2,967) | 0
Held-to-maturity, gross unrealized losses | (9,477) | (901)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 114,450 | 148,979
Available-for-sale, greater than 12 continuous months, fair value | 7,845 | 8,549
Available-for-sale, total securities in a loss position, fair value | 122,295 | 157,528
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (5,673) | (2,527)
Available-for-sale, greater than 12 continuous months, unrealized loss | (1,124) | (420)
Available-for-sale, total securities in a loss position, unrealized loss | (6,797) | (2,947)
U.S. Treasury securities |  |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 10,973 | 11,629
Available-for-sale, greater than 12 continuous months, fair value | 0 | 0
Available-for-sale, total securities in a loss position, fair value | 10,973 | 11,629
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (917) | (256)
Available-for-sale, greater than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, total securities in a loss position, unrealized loss | (917) | (256)
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 continuous months | 42,348 | 19,203
Greater than or equal to 12 continuous months | 0 | 0
Total Securities in a loss position | 42,348 | 19,203
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Less than 12 continuous months | (4,667) | (209)
Greater than or equal to 12 continuous months | 0 | 0
Held-to-maturity, gross unrealized losses | (4,667) | (209)
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 102,115 | 17,552
Available-for-sale, greater than 12 continuous months, fair value | 2,243 | 0
Available-for-sale, total securities in a loss position, fair value | 104,358 | 17,552
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (5,153) | (381)
Available-for-sale, greater than 12 continuous months, unrealized loss | (361) | 0
Available-for-sale, total securities in a loss position, unrealized loss | (5,514) | (381)
Corporate bonds |  |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 29,421 | 38,495
Available-for-sale, greater than 12 continuous months, fair value | 5,440 | 0
Available-for-sale, total securities in a loss position, fair value | 34,861 | 38,495
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (1,579) | (506)
Available-for-sale, greater than 12 continuous months, unrealized loss | (549) | 0
Available-for-sale, total securities in a loss position, unrealized loss | (2,128) | (506)
Asset-backed securities |  |
Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Fair Value [Abstract] |  |
Available-for-sale, less than 12 continuous months, fair value | 1,761 | 1,861
Available-for-sale, greater than 12 continuous months, fair value | 0 | 0
Available-for-sale, total securities in a loss position, fair value | 1,761 | 1,861
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (34) | (4)
Available-for-sale, greater than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, total securities in a loss position, unrealized loss | $ (34) | $ (4)

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27337-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27290-111563 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27290-111563 + Details
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27290-111563 + Details
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