Stock Repurchase Program (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Class of Stock Disclosures [Abstract]
Number of shares repurchased	330	1,674	2,750
Average price paid per share	$ 179.41	$ 161.12	$ 122.20
Total cost	$ 59,116	$ 269,801	$ 336,042

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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