Share-based compensation

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Share-based compensation

13. Share-based compensation

Components of share-based compensation expense are as follows:

	Three Months Ended March 31,
(U.S. Dollars, in thousands)	2021		2020
Cost of sales	$	178	$	181
Sales and marketing		717		696
General and administrative		2,529		2,530
Research and development		297		452
Total	$	3,721	$	3,859

	Three Months Ended March 31,
(U.S. Dollars, in thousands)	2021		2020
Stock options	$	661	$	304
Time-based restricted stock awards and units		1,727		2,421
Market-based restricted stock units		897		670
Stock purchase plan		436		464
Total	$	3,721	$	3,859

During the three months ended March 31, 2021 and 2020, the Company issued 50,510 and 33,559 shares, respectively, of common stock related to stock purchase plan issuances, stock option exercises, and the vesting of restricted stock awards and units.