Income Taxes	3 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	9. Income Taxes Our tax provision for interim periods is determined using an estimate of our annual effective tax rate, adjusted for discrete items arising in that quarter. Our effective tax rate differs from the U.S. statutory tax rate primarily due to valuation allowances on our deferred tax assets as it is more likely than not that some or all of our deferred tax assets will not be realized. Income tax expense was $0.3 million and $1.6 million for the three months ended March 31, 2019 and 2018, respectively.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

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