We have been organized and operating as a REIT effective since our taxable year that began on January 1, 2014. As a REIT, we are generally permitted to deduct from our federal taxable income the dividends we pay to our stockholders. The income represented by such dividends is not subject to federal taxation at the entity level but is taxed, if at all, at the stockholder level. The income of our domestic taxable REIT subsidiaries ("TRSs"), which hold our domestic operations that may not be REIT-compliant as currently operated and structured, is subject, as applicable, to federal and state corporate income tax. In addition, we and our subsidiaries continue to be subject to foreign income taxes in jurisdictions in which we have business operations or a taxable presence, regardless of whether assets are held or operations are conducted through subsidiaries disregarded for federal tax purposes or TRSs. We will also be subject to a separate corporate income tax on any gains recognized during a five-year period following the REIT conversion that are attributable to "built-in" gains with respect to the assets that we owned on January 1, 2014. This built-in gains tax has been imposed on our depreciation recapture recognized into income as a result of accounting method changes commenced in our pre-REIT period. If we fail to remain qualified for taxation as a REIT, we will be subject to federal income tax at regular corporate tax rates. Even if we remain qualified for taxation as a REIT, we may be subject to some federal, state, local and foreign taxes on our income and property in addition to taxes owed with respect to our TRS operations. In particular, while state income tax regimes often parallel the federal income tax regime for REITs, many states do not completely follow federal rules and some do not follow them at all.

The significant components of the deferred tax assets and deferred tax liabilities are presented below:



	December 31,
	2014			2015
Deferred Tax Assets:
Accrued liabilities	$	22,236		$	22,107
Deferred rent	3,144			4,426
Net operating loss carryforwards	64,718			69,290
Federal benefit of unrecognized tax benefits	14,859			12,327
Foreign deferred tax assets and other adjustments	8,620			8,698
Valuation allowance	(40,182		)	(60,009		)
	73,395			56,839
Deferred Tax Liabilities:
Other assets, principally due to differences in amortization	(74,782		)	(66,254		)
Plant and equipment, principally due to differences in depreciation	(39,079		)	(23,408		)
	(113,861		)	(89,662		)
Net deferred tax liability	$	(40,466	)	$	(32,823	)

The current and noncurrent deferred tax assets (liabilities) are presented below:



	December 31,
	2014			2015
Deferred tax assets	$	16,655		$	26,668
Deferred tax liabilities	(2,463		)	(4,489		)
Current deferred tax assets, net	$	14,192		$	22,179
Deferred tax assets	$	56,740		$	30,171
Deferred tax liabilities	(111,398		)	(85,173		)
Noncurrent deferred tax liabilities, net	$	(54,658	)	$	(55,002	)

We have federal net operating loss carryforwards, which expire in 2021 through 2033, of $70,820 at December 31, 2015 to reduce future federal taxable income, on which $3,022 of federal tax benefit is expected to be realized. We can carry forward these net operating losses to the extent we do not utilize them in any given available year. We have state net operating loss carryforwards, which expire from 2016 through 2034, on which an insignificant state tax benefit is expected to be realized. We have assets for foreign net operating losses of $66,155, with various expiration dates (and in some cases no expiration date), subject to a valuation allowance of approximately 91%.

Rollforward of the valuation allowance is as follows:



Year Ended December 31,	Balance at Beginning of the Year		Charged (Credited) to Expense			Other Additions		Other Deductions(1)			Balance at End of the Year
2013	$	76,050	$	(27,186	)	$	—	$	(8,586	)	$	40,278
2014	40,278		9,404			—		(9,500		)	40,182
2015	40,182		33,509			—		(13,682		)	60,009

_______________________________________________________________________________


(1)	Primarily due to fluctuations in currency exchange

We receive a tax deduction upon the exercise of non-qualified stock options or upon the disqualifying disposition by employees of incentive stock options and certain shares acquired under our ESPP for the difference between the exercise price and the market price of the underlying common stock on the date of exercise or disqualifying disposition. The tax benefit for non-qualified stock options associated with our TRSs is included in the consolidated financial statements in the period in which compensation expense is recorded. The tax benefit associated with compensation expense recorded in the consolidated financial statements related to incentive stock options associated with our TRSs is recorded in the period the disqualifying disposition occurs. Incremental tax benefits (deficiencies) in excess of compensation expense recorded in the consolidated financial statements are credited (charged) directly to equity and amounted to $2,389, $(60) and $327 for the years ended December 31, 2013, 2014 and 2015, respectively.

The components of income (loss) from continuing operations before provision (benefit) for income taxes and gain on sale of real estate are:



	Year Ended December 31,
	2013		2014			2015
United States	$	63,930	$	202,067		$	179,928
Canada	39,038		46,191			37,131
Other Foreign	56,903		(24,885		)	(54,993		)
	$	159,871	$	223,373		$	162,066

The provision (benefit) for income taxes consists of the following components:



	Year Ended December 31,
	2013			2014			2015
Federal—current	$	92,237		$	118,314		$	13,083
Federal—deferred	(64,441		)	(214,132		)	(9,579		)
State—current	10,152			28,034			522
State—deferred	(8,056		)	(47,814		)	158
Foreign—current	59,170			27,167			31,581
Foreign—deferred	(26,935		)	(8,844		)	1,948
	$	62,127		$	(97,275	)	$	37,713

A reconciliation of total income tax expense and the amount computed by applying the federal income tax rate of 35% to income from continuing operations before provision (benefit) for income taxes and gain on sale of real estate for the years ended December 31, 2013, 2014 and 2015, respectively, is as follows:



	Year Ended December 31,
	2013			2014			2015
Computed "expected" tax provision	$	55,955		$	78,181		$	56,723
Changes in income taxes resulting from:
Tax adjustment relating to REIT	—			(63,333		)	(51,625		)
Deferred tax adjustment and other taxes due to REIT conversion	—			(182,853		)	(9,067		)
State taxes (net of federal tax benefit)	4,384			2,207			2,017
Increase in valuation allowance (net operating losses)	2,832			9,404			33,509
Decrease in valuation allowance (foreign tax credits)	(30,018		)	—			—
Foreign repatriation	44,751			46,356			4,030
Foreign restructuring	17,691			—			—
Impairment of assets and other transaction costs	6,576			2,869			—
Reserve accrual (reversal) and audit settlements (net of federal tax benefit)	(16,322		)	3,175			(2,874		)
Foreign tax rate differential	(33,852		)	(9,496		)	(8,915		)
Disallowed foreign interest, Subpart F income, and other foreign taxes	9,708			12,502			18,022
Other, net	422			3,713			(4,107		)
Provision (Benefit) for Income Taxes	$	62,127		$	(97,275	)	$	37,713

Our effective tax rates for the years ended December 31, 2013, 2014 and 2015 were 38.9%, (43.5)% and 23.3%, respectively. Our effective tax rate is subject to variability in the future due to, among other items: (1) changes in the mix of income between our qualified REIT subsidiaries and our TRSs, as well as between the jurisdictions in which we operate; (2) tax law changes; (3) volatility in foreign exchange gains and losses; (4) the timing of the establishment and reversal of tax reserves; and (5) our ability to utilize net operating losses that we generate.

During 2013, we completed a plan to utilize both current and carryforward foreign tax credits by repatriating approximately $252,700 (approximately $65,200 of which was previously subject to United States taxes) from our foreign earnings. Due to uncertainty in our ability to fully utilize foreign tax credit carryforwards, we previously did not recognize a full benefit for such foreign tax credit carryforwards in our tax provision. As a result, we recorded an increase in our tax provision from continuing operations in the amount of $63,504 in 2013. This increase was offset by decreases of $18,753 from current year foreign tax credits and $23,301 reversal of valuation allowances related to foreign tax credit carryforwards, resulting in a net increase of $21,450 in our tax provision from continuing operations.

As a result of our REIT conversion, we recorded a net tax benefit of $212,151 during the year ended December 31, 2014 for the revaluation of certain deferred tax assets and liabilities associated with the REIT conversion. In 2014, we recorded an increase to the tax provision of $29,298 associated with tax accounting method changes consistent with our REIT conversion, primarily affected through the filing of amended tax returns. The other primary reconciling items between the federal statutory rate of 35% and our overall effective tax rate during the year ended December 31, 2014 was an increase of $46,356 in our tax provision associated with incremental federal and state income taxes and foreign withholding taxes on earnings of our foreign subsidiaries no longer considered permanently invested and other net tax adjustments related to the REIT conversion, including a tax benefit of $63,333 primarily related to the dividends paid deduction.

The primary reconciling items between the federal statutory rate of 35% and our overall effective tax rate for the year ended December 31, 2015 were the benefit derived from the dividends paid deduction of $51,625 and an out-of-period tax adjustment ($9,067 tax benefit) recorded during the third quarter to correct the valuation of certain deferred tax assets associated with the REIT conversion that occurred in 2014, partially offset by valuation allowances on certain of our foreign net operating losses of $33,509, primarily related to our foreign subsidiaries in Argentina, Brazil, France and Russia.

As a REIT, we are entitled to a deduction for dividends paid, resulting in a substantial reduction of federal income tax expense. As a REIT, substantially all of our income tax expense will be incurred based on the earnings generated by our foreign subsidiaries and our domestic TRSs.

The evaluation of an uncertain tax position is a two-step process. The first step is a recognition process whereby we determine whether it is more likely than not that a tax position will be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The second step is a measurement process whereby a tax position that meets the more likely than not recognition threshold is calculated to determine the amount of benefit to recognize in the financial statements. The tax position is measured at the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement.

We have elected to recognize interest and penalties associated with uncertain tax positions as a component of the provision (benefit) for income taxes in the accompanying Consolidated Statements of Operations. We recorded an increase of $1,459, $1,462 and $2,173 for gross interest and penalties for the years ended December 31, 2013, 2014 and 2015, respectively. We had $5,884 and $7,120 accrued for the payment of interest and penalties as of December 31, 2014 and 2015, respectively.

A summary of tax years that remain subject to examination by major tax jurisdictions is as follows:




Tax Years		Tax Jurisdiction
See Below		United States—Federal and State
2006 to present		Canada
2010 to present		United Kingdom

The normal statute of limitations for United States federal tax purposes is three years from the date the tax return is filed; however, the statute of limitations may remain open for periods longer than three years in instances where a federal tax examination is in progress. The 2012, 2013 and 2014 tax years remain subject to examination for United States federal tax purposes as well as net operating loss carryforwards utilized in these years. We utilized net operating losses from 2000, 2001, 2008 and 2009 in our federal income tax returns for these tax years. The normal statute of limitations for state purposes is between three to five years. However, certain of our state statute of limitations remain open for periods longer than this when audits are in progress.

We are subject to income taxes in the United States and numerous foreign jurisdictions. We are subject to examination by various tax authorities in jurisdictions in which we have business operations or a taxable presence. We regularly assess the likelihood of additional assessments by tax authorities and provide for these matters as appropriate. As of December 31, 2014, we had $55,951 of reserves related to uncertain tax positions, of which $53,078 and $2,873 is included in other long-term liabilities and deferred income taxes, respectively, in the accompanying Consolidated Balance Sheet. As of December 31, 2015, we had $47,685 of reserves related to uncertain tax positions, of which $45,256 and $2,429 is included in other long-term liabilities and deferred income taxes, respectively, in the accompanying Consolidated Balance Sheet. Although we believe our tax estimates are appropriate, the final determination of tax audits and any related litigation could result in changes in our estimates.

A reconciliation of unrecognized tax benefits is as follows:



Gross tax contingencies—December 31, 2012	$	37,563
Gross additions based on tax positions related to the current year	5,985
Gross additions for tax positions of prior years	20,275
Gross reductions for tax positions of prior years	(1,370		)
Lapses of statutes	(1,312		)
Settlements	(9,995		)
Gross tax contingencies—December 31, 2013	$	51,146
Gross additions based on tax positions related to the current year	3,984
Gross additions for tax positions of prior years	13,717
Gross reductions for tax positions of prior years	(2,699		)
Lapses of statutes	(5,350		)
Settlements	(4,847		)
Gross tax contingencies—December 31, 2014	$	55,951
Gross additions based on tax positions related to the current year	3,484
Gross additions for tax positions of prior years	979
Gross reductions for tax positions of prior years	(3,588		)
Lapses of statutes	(9,141		)
Settlements	—
Gross tax contingencies—December 31, 2015	$	47,685

The reversal of these reserves of $47,685 ($36,062 net of federal tax benefit) as of December 31, 2015 will be recorded as a reduction of our income tax provision if sustained. We believe that it is reasonably possible that an amount up to approximately $2,730 of our unrecognized tax positions may be recognized by the end of 2016 as a result of a lapse of statute of limitations or upon closing and settling significant audits in various worldwide jurisdictions.