Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Share-based Payment Arrangement [Abstract]

Stock Option Valuation Assumptions

The compensation cost related to these awards is based on the grant date fair value and is expensed over the vesting period (generally one to five years). We use the Black-Scholes-Merton option pricing model to estimate the fair value of stock option awards.

Stock Option Activity

The following table represents stock option award activity for the year ended December 31, 2020:

	Shares	Wtd. Avg. Exer. Price
Options outstanding, beginning of period	324,324	$	27.68
Options expired	(20,619)	$	26.96
Options outstanding, end of period	303,705	$	27.73
Options exercisable, end of period	206,179	$	28.41

Restricted Stock Units Activity

The following table provides information regarding restricted stock unit activity for the year ended December 31, 2020:

	Shares	Wtd. Avg. Grant Price
Restricted units outstanding, beginning of period	342,683	$	22.10
Restricted stock units granted	397,285	$	2.83
Restricted stock units forfeited	(6,326)	$	19.46
Restricted stock units vested	(158,726)	$	21.38
Restricted stock units outstanding, end of period	574,916	$	9.02