v3.8.0.1

Income taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income taxes

Schedule of income tax (benefit) expense by jurisdiction

		2017			2016			2015
U.S. federal:
Current		$	(6	)	$	55		$	27
Deferred			(2,787	)		345			319
​	​	​	​	​	​	​	​	​	​	​
Total U.S. federal		$	(2,793	)	$	400		$	346
​	​	​	​	​	​	​	​	​	​	​
​	​	​	​	​	​	​	​	​	​	​
U.S. state and local:
Current		$	503		$	69		$	134
Deferred			212			(42	)		1
​	​	​	​	​	​	​	​	​	​	​
Total U.S. state and local		$	715		$	27		$	135
​	​	​	​	​	​	​	​	​	​	​
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Schedule of reconciliation of tax rates

		2017			2016			2015
Federal statutory rate			34.0	%		34.0	%		34.0	%
State and local			9.6			2.2			4.1
Foreign rate differential			(0.7	)		(0.4	)		(0.5	)
Stock options			0.4			(1.5	)		(1.5	)
Excess tax benefits from stock-based compensation			34.3			2.8			—
Non-controlling interests			1.1			0.6			0.5
Valuation allowance			(83.6	)		(38.9	)		(39.0	)
Uncertain tax positions			0.6			(0.2	)		(0.1	)
Effect of U.S. tax reform law changes			14.7			—			—
Other			(0.4	)		(0.2	)		0.3
​	​	​	​	​	​	​	​	​	​	​
Income taxes			10.0	%		(1.6	)%		(2.2	)%
​	​	​	​	​	​	​	​	​	​	​
​	​	​	​	​	​	​	​	​	​	​

Schedule of deferred tax assets and liabilities

		2017			2016
Deferred tax assets:
Net operating loss carryforwards		$	23,838		$	23,669
Outside basis differences for U.S. partnerships			14,306			16,121
Stock options			4,100			5,307
Deferred revenue			748			526
Deferred compensation			249			199
State taxes			78			49
Other			1,282			1,622
Valuation allowance			(34,990	)		(36,331	)
​	​	​	​	​	​	​	​
Net deferred tax assets			9,611			11,162
Deferred tax liabilities:
Intangible assets			(3,632	)		(5,658	)
Property and equipment			(6,983	)		(8,712	)
​	​	​	​	​	​	​	​
Net deferred tax liabilities			(10,615	)		(14,370	)
​	​	​	​	​	​	​	​
Net deferred taxes		$	(1,004	)	$	(3,208	)
​	​	​	​	​	​	​	​
​	​	​	​	​	​	​	​

Schedule of changes in the valuation allowance

		Valuation Allowance
Balance, December 31, 2014		$	12,470
Additions charged to operations			7,078
Decrease credited to operations			—
​	​	​	​	​
Balance, December 31, 2015			19,548
Additions charged to operations			16,783
Decrease credited to operations			—
​	​	​	​	​
Balance, December 31, 2016			36,331
Additions charged to operations			16,527
Effect of U.S. tax reform law changes			(17,868	)
Decrease credited to operations			—
​	​	​	​	​
Balance, December 31, 2017		$	34,990
​	​	​	​	​
​	​	​	​	​

Schedule of reconciliation of unrecognized tax benefits, excluding interest and penalties

		Uncertain Tax Positions
Balance, December 31, 2015 and 2016		$	313
Additions for current period tax positions			—
Reversals during the current period			(313	)
​	​	​	​	​
Balance, December 31, 2017		$	—
​	​	​	​	​
​	​	​	​	​

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Tabular disclosure of the change in unrecognized tax benefits.

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Tabular disclosure of valuation allowances to reduce deferred tax assets to net realizable value, including identification of the deferred tax asset more likely than not will not be fully realized and the corresponding amount of the valuation allowance.

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