Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of the components of the Company's income tax expense

The components of the Company’s income tax expense for the years ended December 31, 2015, 2016, and 2017 were as follows:



	For the Year Ended December 31,
	2015			2016			2017
	(in thousands)
Current income tax expense:
Federal	$	63,626		$	54,726		$	45,809
State and local	10,868			13,329			8,331
Total current income tax expense	74,494			68,055			54,140
Deferred income tax expense (benefit)	(2,058		)	(12,591		)	(72,324		)
Total income tax expense (benefit)	$	72,436		$	55,464		$	(18,184	)

Schedule of reconciliations of the statutory federal income tax rate to the effective income tax rate

Reconciliations of the statutory federal income tax rate to the effective income tax rate are as follows:



	For the Year Ended December 31,
	2015		2016		2017
Federal income tax at statutory rate	35.0	%	35.0	%	35.0	%
State and local income taxes, less federal income tax benefit	4.0		3.6		3.7
Permanent differences	1.4		1.4		1.7
Tax benefit from the sale of businesses	—		(6.7	)	—
Valuation allowance	(0.9	)	0.2		(7.3	)
Uncertain tax positions	(2.3	)	(1.3	)	(0.6	)
Non-controlling interest	(2.0	)	(0.5	)	0.5
Stock-based compensation	—		(0.7	)	(1.3	)
Deferred income taxes - state income tax rate adjustment	—		—		(2.8	)
Deferred income taxes - tax legislation rate adjustment	—		—		(37.5	)
Other	(0.4	)	(0.3	)	(0.4	)
Total effective income tax rate	34.8	%	30.7	%	(9.0	)%

Schedule of the Company's deferred tax assets and liabilities

The Company’s deferred tax assets and liabilities are as follows:



	December 31,
	2016			2017
	(in thousands)
Deferred tax assets
Allowance for doubtful accounts	$	10,735		$	8,792
Compensation and benefit-related accruals	70,199			50,936
Professional malpractice liability insurance	19,763			11,036
Deferred revenue	746			319
Net operating loss carryforwards	39,481			36,112
Stock options	9,533			6,591
Equity investments	1,567			1,452
Uncertain tax positions	499			503
Other	3,496			3,040
Deferred tax assets	$	156,019		$	118,781
Valuation allowance	(26,421		)	(12,986		)
Deferred tax assets, net of valuation allowance	$	129,598		$	105,795
Deferred tax liabilities
Deferred income	$	(26,068	)	$	(19,608	)
Investment in unconsolidated affiliates	(3,885		)	(4,457		)
Depreciation and amortization	(271,914		)	(179,055		)
Deferred financing costs	—			(4,528		)
Other	(5,413		)	(3,673		)
Deferred tax liabilities	$	(307,280	)	$	(211,321	)
Deferred tax liabilities, net of deferred tax assets	$	(177,682	)	$	(105,526	)

The Company’s deferred tax assets and liabilities are included in the consolidated balance sheet captions as follows:



	December 31,
	2016			2017
	(in thousands)
Other assets	$	21,396		$	19,391
Non-current deferred tax liability	(199,078		)	(124,917		)
	$	(177,682	)	$	(105,526	)

Schedule of state net operating loss carry forwards

The total state net operating losses are approximately $596.7 million. State net operating loss carryforwards expire and are subject to valuation allowances as follows:



	State Net Operating Losses		Gross Valuation Allowance
	(in thousands)
2018	$	1,812	$	1,081
2019	9,770		8,788
2020	10,483		8,333
2021	12,269		6,817
Thereafter through 2036	562,326		426,138