Stockholders' Equity

Accumulated Other Comprehensive Loss

The changes in accumulated other comprehensive loss, net of tax, by components are as follows (in thousands):



	Balance as of December 31, 2017			Net Change			Cumulative Effect Adjustment			Balance as of June 30, 2018
Foreign currency translation adjustment ("CTA") loss	$	(576,860	)	$	(275,382	)	$	—		$	(852,242	)
Unrealized gain (loss) on cash flow hedges ⁽¹⁾	(24,191		)	31,200			—			7,009
Unrealized gain (loss) on available-for-sale securities ⁽²⁾	2,124			—			(2,124		)	—
Net investment hedge CTA gain (loss) ⁽¹⁾	(185,303		)	153,480			—			(31,823		)
Net actuarial gain (loss) on defined benefit plans ⁽³⁾	(959		)	21			—			(938		)
Total	$	(785,189	)	$	(90,681	)	$	(2,124	)	$	(877,994	)


⁽¹⁾	Refer to Note 5 for a discussion of the amounts reclassified from accumulated other comprehensive loss to net income.


⁽²⁾	Upon adoption of ASU 2016-01 during the three months ended March 31, 2018, the Company recorded a net cumulative effect adjustment of $2.1 million from accumulated other comprehensive loss to retained earnings.

⁽³⁾

The Company has a defined benefit pension plan covering all employees in one country where such plan is mandated by law. The Company does not have any defined benefit plans in any other countries. The unamortized gain (loss) on defined benefit plans includes gains or losses resulting from a change in the value of either the projected benefit obligation or the plan assets resulting from a change in an actuarial assumption, net of amortization.

Changes in foreign currencies can have a significant impact to the Company’s consolidated balance sheets (as evidenced above in the Company’s foreign currency translation loss), as well as its consolidated results of operations, as amounts in foreign currencies are generally translated into more U.S. dollars when the U.S. dollar weakens or less U.S. dollars when the U.S. dollar strengthens. As of June 30, 2018, the U.S. dollar was generally stronger relative to certain of the currencies of the foreign countries in which the Company operates as compared to December 31, 2017. This overall strengthening of the U.S. dollar had an overall unfavorable impact on the Company's condensed consolidated financial position because the foreign denominations translated into less U.S. dollars as evidenced by an increase in foreign currency translation loss for the six months ended June 30, 2018 as reflected in the above table. In future periods, the volatility of the U.S. dollar as compared to the other currencies in which the Company operates could have a significant impact on its condensed consolidated financial position and results of operations including the amount of revenue that the Company reports in future periods.

Common Stock

In August 2017, the Company entered into an equity distribution agreement with RBC Capital Market, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated, Citigroup Global Markets Inc. and J.P. Morgan Securities LLC, establishing an "at the market" equity offering program, under which the Company may offer and sell from time to time up to an aggregate of $750.0 million of its common stock in "at the market" transactions (the "ATM Program"). For the first half of 2018, the Company sold 19,100 shares under the ATM Program, for approximately $7.6 million, net of payment of commissions to the sales agents. As of June 30, 2018, the Company had generated net proceeds of $363.3 million under the ATM Program.

Dividends

On May 2, 2018, the Company declared a quarterly cash dividend of $2.28 per share, with a record date of May 23, 2018 and a payment date of June 20, 2018. During the three months ended June 30, 2018, the Company paid a total of $181.8 million in dividends. In addition, the Company accrued an additional $2.8 million in dividends payable for restricted stock units that have not yet vested.

On February 14, 2018, the Company declared a quarterly cash dividend of $2.28 per share, with a record date of February 26, 2018 and a payment date of March 21, 2018. During the three months ended March 31, 2018, the Company paid a total of $187.0 million in dividends. In addition, the Company accrued an additional $2.2 million in dividends payable for restricted stock units that have not yet vested.

Stock-Based Compensation

In the first half of 2018, the Compensation Committee and/or the Stock Award Committee of the Company's Board of Directors, as the case may be, approved the issuance of an aggregate of 546,375 shares of restricted stock units to certain employees, including executive officers, pursuant to the 2000 Equity Incentive Plan, as part of the Company's annual refresh program. These equity awards are subject to vesting provisions and have a weighted-average grant date fair value of $379.83 and a weighted-average requisite service period of 3.56 years. The valuation of restricted stock units with only a service condition or a service and performance condition require no significant assumptions as the fair value for these types of equity awards is based solely on the fair value of the Company's stock price on the date of grant. The Company used revenues and adjusted funds from operations ("AFFO") as the performance measurements in the restricted stock units with both service and performance conditions that were granted in the first half of 2018.

The Company uses a Monte Carlo simulation option-pricing model to determine the fair value of restricted stock units with a service and market condition. The Company used total shareholder return (“TSR”) as the performance measurement in the restricted stock units with a service and market condition that were granted in 2018. There were no significant changes in the assumptions used to determine the fair value of restricted stock units with a service and market condition that were granted in 2018 compared to the prior year.

The following table presents, by operating expense category, the Company's stock-based compensation expense recognized in the Company's condensed consolidated statements of operations (in thousands):



	Three Months Ended June 30,				Six Months Ended June 30,
	2018		2017		2018		2017
Cost of revenues	$	4,607	$	3,178	$	8,506	$	6,089
Sales and marketing	14,108		13,426		25,814		24,398
General and administrative	31,010		29,021		57,941		53,461
Total	$	49,725	$	45,625	$	92,261	$	83,948