Cover Page - shares	9 Months Ended
	Sep. 30, 2019	Nov. 06, 2019
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	000-55522
Entity Registrant Name	NATIONAL WESTERN LIFE GROUP, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-3339380
Entity Address, Address Line One	10801 N. Mopac Expy Bldg 3
Entity Address, City or Town	Austin,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	78759
City Area Code	(512)
Local Phone Number	836-1010
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0001635984
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false
Class A
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding (shares)		3,436,020
Class B
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding (shares)		200,000