Stockholders' Equity

12 Months Ended

Dec. 31, 2016

Equity [Abstract]

Stockholders' Equity

STOCKHOLDERS’ EQUITY

Preferred Stock

We have authorized 500 million shares of $0.01 par value preferred stock. No preferred stock was outstanding for any period presented.

Common Stock

Common shares outstanding plus shares underlying outstanding stock awards totaled 483 million, 490 million, and 497 million, as of December 31, 2014, 2015, and 2016. These totals include all vested and unvested stock awards outstanding, including those awards we estimate will be forfeited.

Stock Repurchase Activity

In February 2016, the Board of Directors authorized a program to repurchase up to $5.0 billion of our common stock, with no fixed expiration. This stock repurchase authorization replaced the previous $2.0 billion stock repurchase authorization, approved by the Board of Directors in 2010. There were no repurchases of common stock in 2014, 2015, or 2016.

Stock Award Plans

Employees vest in restricted stock unit awards and stock options over the corresponding service term, generally between two and five years.

Stock Award Activity

Stock options outstanding, which were primarily obtained through acquisitions, totaled 0.4 million, 0.2 million and 0.1 million, as of December 31, 2014, 2015, and 2016. The compensation expense for stock options, the total intrinsic value for stock options outstanding, the amount of cash received from the exercise of stock options, and the related tax benefits were not material for 2014, 2015, and 2016.

Stock-based compensation expense is as follows (in millions):

	Year Ended December 31,
	2014		2015		2016
Cost of sales (1)	$	—	$	—	$	16
Fulfillment	375		482		657
Marketing	125		190		323
Technology and content	804		1,224		1,664
General and administrative	193		223		315
Total stock-based compensation expense	$	1,497	$	2,119	$	2,975

___________________

(1) Beginning in 2016, stock-based compensation expense was recorded to cost of sales for eligible employees providing delivery services.

The following table summarizes our restricted stock unit activity (in millions):

	Number of Units		Weighted Average Grant-Date Fair Value
Outstanding as of January 1, 2014	16.3		$	233
Units granted	8.5		328
Units vested	(5.1	)	202
Units forfeited	(2.3	)	264
Outstanding as of December 31, 2014	17.4		285
Units granted	9.8		426
Units vested	(5.6	)	253
Units forfeited	(2.7	)	321
Outstanding as of December 31, 2015	18.9		362
Units granted	9.3		660
Units vested	(6.1	)	321
Units forfeited	(2.3	)	440
Outstanding as of December 31, 2016	19.8		$	506

Scheduled vesting for outstanding restricted stock units as of December 31, 2016, is as follows (in millions):

		Year Ended December 31,
	2017	2018	2019	2020	2021	Thereafter	Total
Scheduled vesting—restricted stock units	7.0	7.2	3.5	1.6	0.2	0.3	19.8

As of December 31, 2016, there was $4.5 billion of net unrecognized compensation cost related to unvested stock-based compensation arrangements. This compensation is recognized on an accelerated basis with approximately half of the compensation expected to be expensed in the next twelve months, and has a weighted-average recognition period of 1.2 years.

During 2014, 2015, and 2016, the fair value of restricted stock units that vested was $1.7 billion, $2.7 billion, and $4.3 billion.

As matching contributions under our 401(k) savings plan, we granted 0.2 million and 0.1 million shares of common stock in 2015 and 2016. Shares granted as matching contributions under our 401(k) plan are included in outstanding common stock when issued, and recorded as stock-based compensation expense.

Common Stock Available for Future Issuance

As of December 31, 2016, common stock available for future issuance to employees is 123 million shares.