	Three Months Ended
	March 31,
(in thousands)	2019			2018
Performance unit incentive plan (“PUP”)	$	1,423		$	194
Restricted stock		693			503
Restricted stock units		90			20
Share-based compensation before income tax benefit		2,206			717
Income tax benefit		(558	)		(181	)
Share-based compensation, net of income tax benefit	$	1,648		$	536

We did not record any share-based compensation expense through restructuring charges during the three months ended March 31, 2019 or 2018.

The following table summarizes the activity of the outstanding share-based compensation awards:

	PUP Awards					Restricted Stock					Restricted Stock Units
	Shares			Weighted-Average Grant Date Fair Value		Shares			Weighted-Average Grant Date Fair Value		Shares			Weighted-Average Grant Date Fair Value
Balance at December 31, 2018		239,809		$	40.65		176,769		$	40.87		12,090		$	39.04
Granted		73,020		$	58.25		54,475		$	57.80		5,025		$	56.81
Vested		(95,309	)	$	26.98		(80,859	)	$	31.78		(5,377	)	$	26.98
Forfeited		—		$	—		(936	)	$	43.75		—		$	—
Balance at March 31, 2019		217,520		$	52.55		149,449		$	51.93		11,738		$	52.17

We grant share-based compensation awards to our officers, directors, and certain key employees pursuant to the 2017 Viad Corp Omnibus Incentive Plan (the “2017 Plan”). The 2017 Plan has a 10-year life and provides for the following types of awards: (a) incentive and non-qualified stock options; (b) restricted stock and restricted stock units; (c) performance units or performance shares; (d) stock appreciation rights; (e) cash-based awards; and (f) certain other stock-based awards. In June 2017, we registered 1,750,000 shares of common stock issuable under the 2017 Plan. As of March 31, 2019, there were 1,580,999 shares available for future grant under the 2017 Plan.

The vesting of PUP award shares is based upon achievement of certain performance-based criteria. The performance period of the shares is three years.

During the three months ended March 31, 2019, we granted PUP awards with a grant date fair value of $4.3 million of which $1.7 million are payable in shares. Liabilities related to PUP awards were $2.7 million as of March 31, 2019 and $7.0 million as of December 31, 2018. In 2019, PUP awards granted in 2016 vested and we paid $5.6 million in cash and $3.4 million in shares. In 2019, we withheld 25,771 shares for $1.5 million related to tax withholding requirements on vested PUP awards paid in shares. In 2018, PUP awards granted in 2015 vested and we distributed cash payouts of $5.9 million.

As of March 31, 2019, the unamortized cost of outstanding restricted stock awards was $4.9 million, which we expect to recognize over a weighted-average period of approximately 1.7 years. We repurchased 24,067 shares for $1.4 million during the three months ended March 31, 2019 and 16,362 shares for $0.9 million during the three months ended March 31, 2018 related to tax withholding requirements on vested share-based awards.

Aggregate liabilities related to restricted stock units were $0.2 million as of March 31, 2019 and $0.4 million as of December 31, 2018. In February 2019, the 2016 restricted stock units vested and we distributed $0.3 million in cash payouts. In February 2018, the 2015 restricted stock units vested and we distributed $0.2 million in cash payouts.

	Shares		Weighted-Average Exercise Price
Options outstanding and exercisable at December 31, 2018		58,689	$	16.62
Exercised		—	$	—
Options outstanding and exercisable at March 31, 2019		58,689	$	16.62