Stockholders' Equity and Noncontrolling Interests - Summary of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Equity [Abstract]
Weighted average shares outstanding (in shares)	26,881,700	26,885,719
Incremental shares form RS award and RSUs (in shares)	9,975	6,185
Total shares for diluted calculations (in shares)	26,891,675	26,891,904
Net income (loss) attributable to American National (in thousands)	$ (220,444)	$ 258,217
Basic earnings per share (in usd per share)	$ (8.20)	$ 9.60
Diluted earnings per share (in usd per share)	$ (8.20)	$ 9.60

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

AMERICAN NATIONAL INSURANCE CO 10-Q