Schedule of Common Stock Repurchases (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Stockholders Equity Note [Abstract]
Shares repurchased	103,025	62,540
Cost of shares repurchased	$ 63,192	$ 44,268
Average price per share repurchased	$ 613.36	$ 707.84

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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