Common stock buyback program: (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Common stock buyback program:
Purchase of common stock under buy back program				$ 11,517
Purchase of common stock under buyback program (in shares)	0	229,507	0
Remaining authorized amount for common stock repurchases	$ 105,800		$ 105,800
Cost of shares of common stock		$ 11,500

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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+ Details

- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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