Subsequent Event	6 Months Ended
Jun. 30, 2020
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventAs part of the previously announced "Mercury Giveback" program related to reduced driving and business activities during the COVID-19 pandemic, the Company plans to return approximately $22 million of July premiums to its eligible policyholders in August 2020. Accordingly, the Company expects third quarter premiums earned and written to be reduced by approximately $22 million as a result of the refunds. The extension of the Giveback program through July 31, 2020 brings the total premium returned to the Company’s eligible policyholders to approximately $128 million since the beginning of the COVID-19 pandemic.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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