14. Income Taxes

The table below summarizes significant components of deferred tax assets and liabilities.

	Year Ended December 31,
	2016			2015
Deferred tax assets
Allowance for doubtful accounts	$	17,220		$	17,953
Accrued vacation and bonus		38,596			37,481
Deferred rent		12,034			13,415
Share-based compensation		24,783			30,037
Notes receivable from employees		21,010			20,353
State net operating loss carryforward and credits		4,169			3,883
Foreign net operating loss carryforward		12,437			6,614
Future foreign tax credit asset		2,545			3,753
Deferred compensation		3,084			2,279
Other, net		5,284			3,754
Total deferred tax assets		141,162			139,522
Deferred tax liabilities
Revenue recognition		(11,590	)		(12,452	)
Property, equipment and capitalized software		(6,527	)		(5,739	)
Goodwill and other intangible asset amortization		(273,990	)		(247,951	)
Total deferred tax liabilities		(292,107	)		(266,142	)
Valuation allowance		(18,900	)		(13,167	)
Net deferred tax liabilities	$	(169,845	)	$	(139,787	)

As of December 31, 2016, we have not provided for deferred taxes on $81.7 million of the undistributed non-U.S. subsidiary earnings that are considered permanently invested. If these earnings were distributed in the form of dividends or otherwise, the distributors would be subject to U.S. federal income tax of approximately $28.6 million.

As of December 31, 2016 and 2015, the Company believed certain deferred tax assets principally associated with foreign net operating loss, foreign tax credit carryforwards and other related foreign balance sheet accounts, which can be carried forward for periods ranging from 20 years to indefinite, would expire unused based on updated forward-looking financial information. Therefore, valuation allowances of $18.9 million and $13.2 million were recorded against the Company’s net deferred tax assets as of December 31, 2016 and 2015, respectively.

As of December 31, 2016, we have not recorded a $15.4 million deferred tax liability related to the tax basis difference in the investment in our foreign subsidiaries as the investment is considered permanent in duration.

The table below summarizes the components of income before income tax provision from continuing operations.

	Year Ended December 31,
	2016		2015		2014
Domestic	$	66,202	$	59,408	$	60,315
Foreign		61,601		45,978		41,096
Total	$	127,803	$	105,386	$	101,411

The table below summarizes the components of income tax provision from continuing operations.

	Year Ended December 31,
	2016			2015		2014
Current
Federal	$	(3,326	)	$	23,957	$	288
State		1,686			1,943		4,681
Foreign		13,864			10,029		14,042
		12,224			35,929		19,011
Deferred
Federal		23,182			1,546		21,657
State		8,284			1,265		2,309
Foreign		(1,407	)		593		(373	)
		30,059			3,404		23,593
Income tax provision	$	42,283		$	39,333	$	42,604

Our income tax provision from continuing operations resulted in effective tax rates that varied from the statutory federal income tax rate as summarized below.

	Year Ended December 31,
	2016			2015			2014
Income tax expense at federal statutory rate	$	44,731		$	36,885		$	35,494
State income taxes, net of federal benefit		6,075			1,587			3,494
Benefit from lower foreign tax rates		(7,827	)		(5,973	)		(4,154	)
Valuation allowance on foreign tax credits and net operating loss carryforward		254			2,326			4,604
Other expenses not deductible for tax purposes		3,082			2,719			2,962
Adjustment to reserve for uncertain tax positions		(3,547	)		658			220
Other adjustments, net		(485	)		1,131			(16	)
Income tax provision	$	42,283		$	39,333		$	42,604

We file numerous consolidated and separate income tax returns in the U.S. federal jurisdiction and in many city, state and foreign jurisdictions. We are no longer subject to U.S. federal income tax examinations for years prior to 2012. We are also no longer subject to state and local or foreign tax examinations by tax authorities for years prior to 2010.

Our liability for uncertain tax positions was $2.7 million and $8.1 million as of December 31, 2016 and 2015, respectively. The $5.4 million decrease in our liability for uncertain tax positions was primarily due to closure of certain income tax audits. As of December 31, 2016, our accrual for the payment of tax-related interest and penalties was not material.