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Summary of Significant Accounting Policies - Summary of Corrections (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Basis Of Presentation [Line Items] |  |  |
Proceeds from sales of investment securities available for sale | $ 565,400 | $ 2,649,686 | $ 2,923,787
Purchases of investment securities available for sale | (6,877,712) | (6,036,179) | (4,300,021)
Net cash used in investing activities | $ 4,384,166 | 2,352,973 | $ 2,153,862
As Reported |  |  |
Basis Of Presentation [Line Items] |  |  |
Proceeds from sales of investment securities available for sale |  | 4,054,670 |
Purchases of investment securities available for sale |  | (7,441,163) |
Net cash used in investing activities |  | 2,352,973 |
Adjustment |  |  |
Basis Of Presentation [Line Items] |  |  |
Proceeds from sales of investment securities available for sale |  | (1,404,984) |
Purchases of investment securities available for sale |  | 1,404,984 |
Net cash used in investing activities |  | $ 0 |

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- Definition Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3521-108585 + Details
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