Stockholders' Equity and Restrictions Change in Common Shares (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Mar. 04, 2004
Class of Stock [Line Items]
Common stock, shares authorized (in shares)					127,000,000
Treasury Stock, Common
Class of Stock [Line Items]
Common Stock, Shares, Issued	5,330,000	4,937,000	4,138,000	3,136,000
Common Stock Class A [Member]
Class of Stock [Line Items]
Common Stock, Shares, Issued	53,882,661	53,758,176	53,170,000	52,654,000
Common stock, shares authorized (in shares)	100,000,000	100,000,000			100,000,000
Stock Issued During Period, Shares, New Issues		22,000
Deferred Compensation Arrangement with Individual, Shares Issued	125,000	91,000	112,000
Stock Repurchased During Period, Shares	0	0	0
Treasury Stock, Shares, Acquired	393,000	799,000
Common Stock Class A [Member] | Stock Investment Plan
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues		475,000	404,000
Common Stock Class B [Member]
Class of Stock [Line Items]
Common Stock, Shares, Issued	1,001,714	1,001,714	1,002,000	1,002,000
Common stock, shares authorized (in shares)	2,000,000	2,000,000			2,000,000
Stock Issued During Period, Shares, New Issues		0
Deferred Compensation Arrangement with Individual, Shares Issued	0	0	0
Stock Repurchased During Period, Shares	0	0	0
Treasury Stock, Shares, Acquired			1,002,000
Common Stock Class B [Member] | Stock Investment Plan
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues		0	0
Preferred Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)					25,000,000
Treasury Stock, Common
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues		0
Deferred Compensation Arrangement with Individual, Shares Issued	0	0	0
Treasury Stock, Common | Stock Investment Plan
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues		0	0