Shareholders' Equity (Narrative) (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 2,800,000
Common stock surrendered as payment	102,031	$ 62,854
Value of common shares remaining to be repurchased	$ 115,018
Repurchases in Accordance with Stock Award Agreements [Member]
Equity, Class of Treasury Stock [Line Items]
Acquisition of treasury stock (shares)	58
Common stock surrendered as payment	$ 47,630

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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