The following table presents the Company’s total revenues separated between revenues from contracts with customers and other sources of revenues (in thousands):

	Three Months Ended March 31,
	2020		2019
Revenue from contracts with customers:
Commissions	$	455,855	$	430,182
Data, software, and post-trade		19,398		17,910
Fees from related parties		5,521		5,795
Other revenues		3,957		2,853
Total revenue from contracts with customers		484,731		456,740
Other sources of revenue:
Principal transactions		113,311		84,230
Interest income		4,161		3,665
Other revenues		964		116
Total revenues	$	603,167	$	544,751

As discussed in Note 1— “Organization and Basis of Presentation”, the Company adopted the new revenue recognition standard as of January 1, 2018. There was no significant impact to the Company’s unaudited condensed consolidated financial statements for the periods presented as a result of applying the new revenue recognition standard.

Refer to Note 3— “Summary of Significant Accounting Policies” in our consolidated financial statements included in Part II, Item 8 of our Annual Report on Form 10-K for the year ended December 31, 2019 for detailed information on the recognition of the Company’s revenues from contracts with customers.

Refer to Note 23—“Segment, Geographic and Product Information,” for a further discussion on the allocation of revenues to geographic regions.

The timing of our revenue recognition may differ from the timing of payment by our customers. The Company records a receivable when revenue is recognized prior to payment and the Company has an unconditional right to payment. Alternatively, when payment precedes the provision of the related services, the Company records deferred revenue until the performance obligations are satisfied.

The Company had receivables related to revenues from contracts with customers of $820.9 million and $778.4 million at March 31, 2020 and December 31, 2019, respectively. The Company had no impairments related to these receivables during the three months ended March 31, 2020 and 2019.

The Company’s deferred revenue primarily relates to customers paying advance or billed in advance where the performance obligation has not yet been satisfied. Deferred revenue at March 31, 2020 and December 31, 2019 was $15.9 million and $12.9 million, respectively. During the three months ended March 31, 2020 and 2019, the Company recognized revenue of $6.4 million and $6.3 million, respectively, that was recorded as deferred revenue at the beginning of the period.

The Company capitalizes costs to fulfill contracts associated with different lines of its business where the revenue is recognized at a point in time and the costs are determined to be recoverable. Capitalized costs to fulfill a contract are recognized at the point in time that the related revenue is recognized.

At March 31, 2020 and December 31, 2019, there were $1.4 million of capitalized costs recognized to fulfill a contract.