Basis of Presentation and Summary of Significant Accounting Policies - Changes in the Balance of Each Component of Accumulated Other Comprehensive Earnings (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Sep. 30, 2026 |
Jun. 30, 2026 |
Mar. 31, 2026 |
Sep. 30, 2025 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Changes in the balance of each component of accumulated other comprehensive earnings (loss) | ||||||||
| Beginning balance | $ 1,752,115 | $ 1,796,390 | $ 1,778,196 | $ 1,734,661 | $ 1,604,212 | $ 1,521,967 | $ 1,778,196 | $ 1,521,967 |
| Net current-period other comprehensive earnings (loss) | (117,809) | (2,314) | (25,366) | 27,674 | 18,701 | 30,030 | (145,489) | 76,405 |
| Ending balance | 1,696,173 | 1,752,115 | 1,796,390 | 1,874,176 | 1,734,661 | 1,604,212 | 1,696,173 | 1,874,176 |
| Balance of securities for which an allowance for credit losses has been recognized in net earnings | 1,989 | 1,715 | 1,989 | 1,715 | ||||
| Unrealized Gains and Losses on Available-for-Sale Securities | ||||||||
| Changes in the balance of each component of accumulated other comprehensive earnings (loss) | ||||||||
| Beginning balance | (115,754) | $ (88,074) | (124,992) | $ (173,723) | (88,074) | (173,723) | ||
| Other comprehensive earnings before reclassifications | (118,861) | 29,431 | (147,493) | 77,253 | ||||
| Amounts reclassified from accumulated other comprehensive earnings | 1,052 | (1,757) | 2,004 | (848) | ||||
| Net current-period other comprehensive earnings (loss) | (117,809) | 27,674 | (145,489) | 76,405 | ||||
| Ending balance | $ (233,563) | $ (115,754) | $ (97,318) | $ (124,992) | $ (233,563) | $ (97,318) | ||
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with allowance for credit loss. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax, before reclassification adjustments of other comprehensive income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of reclassification adjustments of other comprehensive income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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