CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands	Total	Murphy Shareholders' Equity	Cumulative Preferred Stock	Common Stock	Capital In Excess Of Par Value	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock	Noncontrolling Interest
Balance at beginning of period at Dec. 31, 2019				$ 195,089	$ 949,445	$ 6,614,304	$ (574,161)	$ (1,717,217)	$ 337,151
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options, including income tax benefits				12	(156)
Restricted stock transactions and other					(32,604)
Share-based compensation					8,245
Net income (loss) for the period	$ (416,104)					(416,104)			(92,598)
Cash dividends						(38,392)
Foreign currency translation (loss) gain, net of income taxes	(118,411)						(118,411)
Retirement and postretirement benefit plans, net of income taxes							(9,711)
Deferred loss on interest rate hedges reclassified to interest expense, net of income taxes	299						299
Awarded restricted stock, net of forfeitures								25,511
Distributions to noncontrolling interest owners									(32,399)
Balance at end of period at Mar. 31, 2020	5,098,303	$ 4,886,149	$ 0	195,101	924,930	6,159,808	(701,984)	(1,691,706)	212,154
Balance at beginning of period at Dec. 31, 2020	4,394,147			195,101	941,692	5,369,538	(601,333)	(1,690,661)	179,810
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options, including income tax benefits					(39)			39
Restricted stock transactions and other					(33,000)
Share-based compensation					5,650
Net income (loss) for the period	(287,438)					(287,438)			20,614
Cash dividends						(19,287)
Foreign currency translation (loss) gain, net of income taxes	19,897						19,897
Retirement and postretirement benefit plans, net of income taxes							4,136
Deferred loss on interest rate hedges reclassified to interest expense, net of income taxes	1,690						1,690
Awarded restricted stock, net of forfeitures								29,206
Distributions to noncontrolling interest owners									(36,006)
Balance at end of period at Mar. 31, 2021	$ 4,099,609	$ 3,935,191	$ 0	$ 195,101	$ 914,303	$ 5,062,813	$ (575,610)	$ (1,661,416)	$ 164,418