Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2020	Feb. 29, 2020
Dividends, Common Stock, Cash	$ 210,496	$ 209,513	$ 174,355
Common Stock, Dividends, Per Share, Declared	$ 1.00	$ 0.96	$ 0.75
Payments of Ordinary Dividends, Common Stock	$ 209,248	$ 200,271	$ 168,913
Share repurchases (in shares)	4.4	11.3	13.1
Share repurchases	$ 106,529	$ 348,608	$ 523,569
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 444,000
Share Repurchase Program, August 2018
Stock Repurchase Program, Authorized Amount				$ 750,000
Share Repurchase Program 2020
Stock Repurchase Program, Authorized Amount					$ 500,000

Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Number of shares that have been repurchased during the period and are being held in treasury.

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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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