Stockholders' Equity - (Notes)

6 Months Ended

Jun. 30, 2019

STOCKHOLDERS’ EQUITY

Common Stock

The following table presents a rollforward of our common stock for the three and six months ended June 30, 2019 and 2018:



	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Shares issued and outstanding, beginning balance	70,079,747		70,363,251		70,596,559		69,818,392
Issuance of common stock from vested restricted stock units	213,991		389,875		500,710		1,000,141
Issuance of common stock from exercise of stock options	58,491		263,464		139,773		469,894
Issuance of common stock for employee stock purchase plan	112,623		84,525		112,623		84,525
Repurchase of common stock	(392,700	)	(434,766	)	(1,175,609	)	(594,799	)
Awards effectively repurchased for required employee withholding taxes	(81,007	)	(92,462	)	(182,911	)	(204,266	)
Shares issued and outstanding, ending balance	69,991,145		70,573,887		69,991,145		70,573,887

Equity-Based Incentive Plans

Our 2019 Equity Incentive Plan (the 2019 Plan), approved in May 2019, replaced our 2009 Equity Incentive Plan and provides for the grants of options (both non-qualified and incentive stock options), stock appreciation rights, restricted stock, RSUs, performance awards (each as defined in the 2019 Plan) and other cash- and stock-based awards. Shares available for grant as of June 30, 2019 were approximately 2,839,430.

Restricted Stock Units (RSUs) and Restricted Stock Awards (RSAs)

Time-based RSUs and RSAs generally vest over a four-year term. Performance-based RSUs and RSAs are subject to vesting requirements based on certain financial performance metrics as defined in the grant notice. Actual number of shares earned may range from 0% to 200% of the target award. Awards granted in 2019 and 2018 are based on a single-year performance period subject to subsequent multi-year vesting with 50% of the shares earned vesting in one year after the performance period and the remaining shares in the year after.

The following table summarizes RSU and RSA activity under our equity-based plans for the six months ended June 30, 2019:



	RSUs				RSAs
	Number of Units		Weighted-Average Grant Date Fair Value		Number of Units		Weighted-Average Grant Date Fair Value
Nonvested at December 31, 2018	1,737,554		$	32.83	346,792		$	49.13
Granted	724,172		60.58		—		—
Vested	(511,813	)	30.34		(31,248	)	50.61
Forfeited	(106,737	)	36.52		(11,103	)	49.35
Nonvested at June 30, 2019	1,843,176		$	44.18	304,441		$	49.11

Equity-Based Compensation

Stock-based compensation expense is measured based on the fair value of the stock award on the grant date and recognized over the requisite service period for each separately vesting portion of the stock award. Stock-based compensation expense and other disclosures for stock-based awards made to our employees pursuant to the equity plans was as follows:



	Three Months Ended June 30,				Six Months Ended June 30,
(in millions)	2019		2018		2019		2018
Cost of providing services	$	2	$	2	$	4	$	4
Sales and marketing	1		2		1		4
General and administrative	7		5		13		9
Systems development and programming costs	1		1		2		2
Total stock-based compensation expense	$	11	$	10	$	20	$	19

Stock Repurchases

In February 2019, our board of directors authorized a $300 million incremental increase to our ongoing stock repurchase program initiated in May 2014. During the six months ended June 30, 2019, we repurchased 1,175,609 shares of common stock for approximately $62 million. As of June 30, 2019, approximately $313 million remained available for further repurchases of our common stock under all authorizations from our board of directors under this program.