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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Measurement Period

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Share-based Compensation Arrangement by Share-based Payment Award, Vesting Price Determining Period

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- Definition

Share-Based Payment, Performance Period

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Share-based Compensation Arrangement by Share-based Payment Award, Performance Factor, Percentage Of Pre-defined Metric Target

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- Definition

Share-based Compensation Arrangement by Share-based Payment Awards, Plan Extension Period

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of shares authorized for issuance under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Price of a single share of a number of saleable stocks of a company.

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Percentage of vesting of award under share-based payment arrangement.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

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Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

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Stockholders' Equity - Regulatory Capital Requirements and Share-Based Payments - General Descriptions (Details) - USD ($)		12 Months Ended
	Jun. 15, 2016	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jun. 20, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant price (in dollars per share)		$ 218.44	$ 192.10
Compensation cost, liability balance		$ 7,900,000	$ 6,200,000
Intrinsic value of share-based compensation exercised		4,100,000	2,800,000	$ 3,100,000
Fair value of options vested		3,700,000	4,200,000	4,400,000
Proceeds from exercise of stock options		$ 0	0	0
Share price (in dollars per share)		$ 214.44
Pre-tax compensation cost (benefit) recognized		$ 5,800,000	(2,200,000)	2,400,000
Compensation cost (benefit), tax expense (benefit)		(1,200,000)	500,000	(500,000)
Pre-tax compensation expense related to nonvested share-based awards not yet recognized		$ 11,900,000	$ 9,100,000	$ 8,000,000
Compensation cost related to nonvested options not yet recognized, weighted-average period of recognition		1 year 6 months
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Share-base payment, performance period		3 years
Performance outcome period		3 years
Award measurement period			3 years	3 years
Performance factor used to determine compensation payout			85.16%	101.19%
Employees \| Employee Stock Appreciation Rights SARs Granted Before 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards		3 years
Employees \| Employee Stock Appreciation Rights SARs Granted Before 2016 \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Employees \| Employee Stock Appreciation Rights SARs Granted Before 2016 \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Employees \| Employee Stock Appreciation Rights SARs Granted Before 2016 \| Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Employees \| Employee Stock Appreciation Rights SARs Granted Before 2016 \| Tranche Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Employees \| Employee Stock Appreciation Rights SARs Granted Before 2016 \| Tranche Five
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Employees \| Employee Stock Appreciation Rights SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards		1 year
Employees \| Employee Stock Appreciation Rights SARs \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		33.30%
Employees \| Employee Stock Appreciation Rights SARs \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		33.30%
Employees \| Employee Stock Appreciation Rights SARs \| Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		33.30%
Employees \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		100.00%
Requisite service period of awards		3 years		3 years
Award vesting period		3 years
Directors \| Employee Stock Options SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards		1 year
Directors \| Employee Stock Options SARs \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Directors \| Employee Stock Options SARs \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Directors \| Employee Stock Options SARs \| Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Directors \| Employee Stock Options SARs \| Tranche Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Directors \| Employee Stock Options SARs \| Tranche Five
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting percentage		20.00%
Directors \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards		1 year
Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Award vesting price determining period		20 days
Class A \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting price determining period		20 days
Class A \| Employees \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting price determining period		20 days
Class A \| Directors \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting price determining period		20 days
Stock and Incentive Plan, 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan extension term	10 years
Stock and Incentive Plan, 2008 Plan \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value (in dollars per share)					$ 1.00
Share-based payments, number of shares authorized under plans (in shares)					300,000
National Western Life Insurance Company: \| Colorado Division of Insurance
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Current authorized control level RBC		$ 120,600,000
Capital and surplus		1,700,000,000
Ozark National Life Insurance Company: \| Colorado Division of Insurance
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Current authorized control level RBC		7,800,000
Capital and surplus		$ 109,300,000