On January 1, 2018, the Company adopted ASC 606 and applied it to all contracts using the modified retrospective method. The Company recognized the cumulative effect of initially applying the new revenue standard as an adjustment to the opening balance of accumulated deficit. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods.

The cumulative effect of the changes made to the Company’s consolidated January 1, 2018 balance sheet for the adoption of the new revenue standard was as follows (in thousands):

	Balance at December 31, 2017			Adjustments Due to ASC 606		Balance at January 1, 2018
BALANCE SHEET
Assets
Accounts receivable, net	$	31,699		$	100	$	31,799
Deferred costs		2,429			2,132		4,561
Deferred costs (non-current)		—			6,965		6,965
Liabilities and Stockholders’ Equity
Other current liabilities		808			100		908
Deferred revenue (current and non-current)		73,072			—		73,072
Accumulated deficit		(109,252	)		9,097		(100,155	)

The following table disaggregates the Company’s revenue by geography which provides information as to the major source of revenue (in thousands):

	Year Ended December 31,
Primary Geographic Markets	2019		2018
United States	$	157,039	$	119,589
International		43,843		27,505
Total	$	200,882	$	147,094

The following table presents the Company’s revenues disaggregated by revenue source (in thousands):

	Year Ended December 31,
	2019		2018		2017⁽¹⁾
Subscription services	$	179,934	$	137,260	$	100,000
Professional services		17,187		9,538		4,352
Software licenses		3,761		296		—
Total	$	200,882	$	147,094	$	104,352

The Company does not have material amounts of contract assets since revenue is recognized as control of goods is transferred or as services are performed. There are a small number of professional services that may occur over a period of time, but that period of time is generally very short in duration. Any contract assets that may arise are recorded in other assets in the Company’s consolidated balance sheet. As of December 31, 2019, the Company had $2.0 million in receivables related to services performed which were not billed.

The Company’s contract liabilities consist of advance payments and deferred revenue. The Company’s contract liabilities are reported in a net position on a contract-by-contract basis at the end of each reporting period. The Company classifies advance payments and deferred revenue as current or noncurrent based on the timing of when it expects to recognize revenue. Generally, all contract liabilities are expected to be recognized within one year and are included in deferred revenue in the Company’s consolidated balance sheet. The noncurrent portion of deferred revenue is included and separately disclosed in the Company’s consolidated balance sheet.

Current deferred costs, which primarily consist of deferred sales commissions, were $9.9 million and $6.5 million as of December 31, 2019 and 2018, respectively. Noncurrent deferred costs, which primarily consist of deferred sales commissions, were $14.2 million and $10.3 million as of December 31, 2019 and 2018, respectively. During the years ended December 31, 2019 and 2018, amortization expense for the deferred costs was $8.0 million and $5.5 million, respectively. There was no impairment loss in relation to the costs capitalized. During the year ended December 31, 2017, amortization expense for the deferred costs based on the Company’s policy under Topic 605 was $5.9 million and capitalized commissions totaled $2.4 million.

$86.2 million and $62.5 million of subscription services revenue was recognized during the years ended December 31, 2019 and 2018, respectively, and was included in the deferred revenue balances at the beginning of the respective period. $6.0 million of professional services revenue was recognized during the year ended December 31, 2019 and was included in the deferred revenue balance at the beginning of the period.

As of December 31, 2019, approximately $290.8 million of revenue is expected to be recognized from remaining performance obligations for subscription and other contracts. The Company expects to recognize revenue on approximately $162.3 million of these remaining performance obligations over the next 12 months, with the balance recognized thereafter.

As of December 31, 2019, approximately $6.9 million of revenue is expected to be recognized from remaining performance obligations for professional services contracts. The Company expects to recognize revenue on approximately $5.5 million of these remaining performance obligations over the next 12 months, with the balance recognized thereafter.