5. Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Supplemental Cash Flow Elements [Abstract]
Net Income Attributable to Parent	$ 685,912	$ 865,195
Depreciation and Amortization	33,600	32,900
Right-of-use asset amortization	9,600	10,000
Share-based Payment Arrangement, Noncash Expense	9,700	8,500
(Gain) Loss on Sale of Securities, Net	(400)	0
Other than Temporary Impairment Losses on Investments	0	1,600
Changes in fair market value of equity securities	(827,700)	(1,059,200)
Loss on Disposition of Property Plant Equipment	100	300
Changes in fair value of contingent consideration	(100)	(500)
Payments for operating lease liabilities	(9,300)	(11,700)
Decrease in accounts receivable	2,200	(2,000)
Increase in inventories	(13,700)	(11,600)
Increase in other current assets	(9,500)	(16,700)
(Decrease) increase in accounts payable and other current liabilities	(25,600)	20,600
Decrease in income taxes payable	20,900	13,800
Increase in deferred income taxes	171,800	238,500
Increase in other long term liabilities	15,700	(38,300)
Other	(400)	(8,500)
Net cash provided by operating activities	62,808	42,943
Noncash or Part Noncash Acquisition, Fixed Assets Acquired	6,000	5,100
Noncash or Part Noncash Acquisition, Investments Acquired	$ 2,700	$ 0