Acquisitions and Dispositions	12 Months Ended
Dec. 31, 2022
Business Combination and Asset Acquisition [Abstract]
Acquisitions and Dispositions	13. ACQUISITONS AND DISPOSITIONS On September 30, 2022, RLI Corp. completed the sale of its equity method investment in Maui Jim to Kering Eyewear for cash proceeds of $686.6 million. The sale was part of a larger transaction whereby Kering Eyewear acquired all of the shares of common stock of Maui Jim, consistent with our prior commitments under the terms of a shareholders agreement between RLI and the majority owner of Maui Jim. We recognized a net realized gain of $571.0 million as a result of the sale, which was recorded in the net realized gain line item of the statement of earnings. In addition, we have the right to receive additional consideration based on customary post-closing working capital and other adjustments. Any gain related to the additional consideration will be recognized when received.

The entire disclosure for business combinations, including leverage buyout transactions (as applicable), and divestitures. This may include a description of a business combination or divestiture (or series of individually immaterial business combinations or divestitures) completed during the period, including background, timing, and assets and liabilities recognized and reclassified or sold. This element does not include fixed asset sales and plant closings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-URI https://asc.fasb.org/subtopic&trid=2122178

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-URI https://asc.fasb.org/topic&trid=2303972

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