Stockholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	9 Months Ended	12 Months Ended
	Jan. 26, 2023	Sep. 30, 2024	Sep. 30, 2024	Dec. 31, 2023
Equity, Class of Treasury Stock [Line Items]
Treasury stock, shares		6,500,000	6,500,000	6,300,000
Treasury stock, Cost basis		$ 255.1	$ 255.1	$ 236.7
Shares repurchased		300,000	612,993
Excise tax			$ 0.2
2018 Stock Buyback Program [Member]
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized for repurchase	4,300,000
Stock repurchase expiration date	Dec. 31, 2024
2018 Stock Buyback Program [Member] | Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Shares repurchased			612,913	0
Shares purchased average cost per share			$ 48.63
Restricted Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Number of shares nonvested		300,000	300,000	300,000