Stock-Based Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Summary of stock-based compensation expense, net of amounts capitalized

The following summarizes stock-based compensation expense, net of amounts capitalized to development projects, for the years ended December 31:

thousands	2023		2022		2021
Stock Options (a)	$	336	$	250	$	227
Restricted Stock (b)	10,847		6,860		7,332
Pre-tax stock-based compensation expense	$	11,183	$	7,110	$	7,559
Income tax benefit	$	882	$	636	$	882

(a)Amounts shown are net of immaterial amounts capitalized to development projects.

(b)Amounts shown are net of $4.6 million capitalized to development projects in 2023, $4.8 million capitalized to development projects in 2022, and $2.2 million capitalized to development projects in 2021.

Summary of stock option plan activity

The following table summarizes stock option activity:

	Stock Options	Weighted-average Exercise Price		Weighted-average Remaining Contractual Term (years)	Aggregate Intrinsic Value
Stock options outstanding at December 31, 2022	258,987	$	110.20
Forfeited	(8,000)	106.83
Expired	(116,650)	112.09
Stock options outstanding at December 31, 2023	134,337	$	108.76	4.4	$	663,915
Stock options vested and expected to vest at December 31, 2023	133,096	$	109.08	4.4	$	647,298
Stock options exercisable at December 31, 2023	79,500	$	131.19	2.4	$	—

Summary of significant assumptions used in Black-Scholes option-pricing model

The fair value on the grant date and the significant assumptions used in the Black‑Scholes option‑pricing model are as follows:

	2022			2021
Weighted-average grant date fair value	$	37.70		$	41.52
Assumptions
Expected life of options (in years)	7.5			7.5
Risk-free interest rate	3.4		%	1.2		%
Expected volatility	50.3		%	36.5		%
Expected annual dividend per share	—			—

Schedule of restricted stock activity

The following table summarizes restricted stock activity:

	Restricted Stock	Weighted-average Grant Date Fair Value
Restricted stock outstanding at December 31, 2022	353,463	$	75.14
Granted	267,820	83.85
Vested	(119,744)	84.42
Forfeited	(107,841)	68.92
Restricted stock outstanding at December 31, 2023	393,698	$	79.94