| Document and Entity Information | Feb. 04, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Amendment Description | On February 10, 2022, First American Financial Corporation (the “Company”) filed a Current Report on Form 8-K announcing the promotion of Kenneth D. DeGiorgio to chief executive officer on February 4, 2022. At that time, there were no changes to his compensation. On March 8, 2022, the Company’s Compensation Committee increased his base salary from $825,000 to $925,000 per year (effective as of February 4, 2022), increased his full-year 2022 annual incentive plan cash bonus target from $875,000 to $1,750,000 and increased his full-year 2022 annual incentive plan bonus restricted stock unit target from $875,000 to $1,750,000. |
| Document Period End Date | Feb. 4, 2022 |
| Entity Registrant Name | FIRST AMERICAN FINANCIAL CORPORATION |
| Entity Central Index Key | 0001472787 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-34580 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 26-1911571 |
| Entity Address, Address Line One | 1 First American Way |
| Entity Address, City or Town | Santa Ana |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92707-5913 |
| City Area Code | 714 |
| Local Phone Number | 250-3000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, $0.00001 par value |
| Trading Symbol | FAF |
| Security Exchange Name | NYSE |
