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Subsequent Events: (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Feb. 18, 2026	Feb. 05, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Subsequent Events:
Dividends declared per common share			$ 3.05	$ 3.92	$ 3.76
Subsequent Events | Interest rate swap
Subsequent Events:
Payment for settlement		$ 4.1
Cash deposits released		$ 4.3
Subsequent Events | O 2026 Q1 Dividends
Subsequent Events:
Dividends, date of approval	Feb. 18, 2026
Dividends declared per common share	$ 0.02
Dividends, date of record	Mar. 06, 2026
Dividends payable	$ 1.0
Dividends payable date	Mar. 20, 2026

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