Income Taxes: (Schedule of Earnings Before Income Taxes and Provision For Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Earnings before income taxes	$ 13,880	$ 12,199	$ 10,450
United States federal and state:
Current	371	465	201
Deferred	(817)	(81)	(368)
Total United States		384	(167)
Outside United States:
Current	3,182	2,668	2,468
Deferred	10	(35)	38
Total outside United States		2,633	2,506
Total provision for income taxes	$ 2,737	$ 3,017	$ 2,339