all share-based awards issued with no performance conditions. For awards with performance conditions, compensation cost is recognized on an accelerated basis if it is probable that the
performance condition will be achieved.
Forfeitures are estimated based on historical experience and are periodically
reviewed. Cancellation of an award accompanied by the concurrent grant of a replacement award is accounted for as a modification of the terms of the cancelled award, or the modified awards. The compensation costs associated with the modified awards
are recognized if either the original vesting condition or the new vesting condition is achieved. Total recognized compensation cost for the awards is at least equal to the fair value of the awards at the grant date unless at the date of the
modification the performance or service conditions of the original awards are not expected to be satisfied. The incremental compensation cost is measured as the excess of the fair value of the replacement award over the fair value of the cancelled
award at the cancellation date. Therefore, in relation to the modified award, we recognize share-based compensation over the vesting periods of the replacement award, which comprises (i) the amortization of the incremental portion of
share-based compensation over the remaining vesting term, and (ii) any unrecognized compensation cost of the original awards, using either the original term or the new term, whichever results in higher expenses for each reporting period.
We account for share awards issued to non-employees in accordance with the provisions
of ASC subtopic 505-50, or ASC 505-50, Equity: Equity-based Payments to Non-Employees. We use the Black-Scholes-Merton
option pricing model method to measure the value of options granted to non-employees at each vesting date to determine the appropriate charge to share-based compensation. ASC 718 also requires share-based
compensation to be presented in the same manner as cash compensation rather than as a separate line item.
We recognize income taxes under the liability method. Deferred income taxes are recognized for differences between the
financial reporting and tax bases of assets and liabilities at enacted tax rates in effect for the years in which the differences are expected to reverse. We record valuation allowance against the amount of deferred tax assets that we determine is
not more-likely-than-not to be realized. The effect on deferred taxes of a change in tax rates is recognized in earnings in the period that includes the enactment date. For reconciliation of tax computed by
applying the respective statutory income tax rate to pre-tax income, please see Income taxes under Note 12 to our audited consolidated financial statements.
We comply with the provisions of ASC topic 740, or ASC 740, Income Taxes, in accounting for uncertainty in income
taxes. ASC 740 clarified the accounting for uncertainty in income taxes by prescribing the recognition threshold a tax position is required to meet before being recognized in the financial statements. We have elected to classify interest and
penalties related to an uncertain tax position (if and when required) as part of income tax expense in the consolidated statements of comprehensive income. As of and for the years ended December 31, 2014, 2015 and 2016, the amounts of
unrecognized tax benefits as well as interest and penalties associated with uncertainty in income taxes were insignificant.
We adopted ASU No. 2015-17, Income Taxes (Topic 740), Balance Sheet
Classification of Deferred Taxes, which require that all deferred tax liabilities and assets be classified as noncurrent in the consolidated balance sheet starting from the fourth quarter of 2015 on a retrospective basis.
Accounts Receivable, net of Allowance
Accounts receivable are recognized and carried at the original invoiced amount less an allowance for any potential
uncollectible amounts. An estimate for doubtful debts is made when collection of the full amount is no longer probable. Bad debts are written off as incurred. We generally do not require collateral from our customers.
We maintain allowances for doubtful accounts for estimated losses resulting from the failure of customers to make payments on
time. We review the accounts receivable on a periodic basis and make general and specific