The following table presents the Company’s total revenues broken out by revenues from contracts with customers and other sources of revenues for the three and six months ended June 30, 2019 and 2018 (in thousands):

	Three Months Ended June 30,
	2019		2018
Revenues from contracts with customers:
Commissions	$	164,981	$	166,902
Investment banking		179,617		161,063
Asset management and service fees		211,171		199,568
Other		3,748		3,796
Total revenue from contracts with customers		559,517		531,329
Other sources of revenue:
Interest		187,940		154,421
Principal transactions		96,464		88,984
Other		9,757		5,277
Total revenues	$	853,678	$	780,011

	Six Months Ended June 30,
	2019		2018
Revenues from contracts with customers:
Commissions	$	320,430	$	332,677
Investment banking		341,457		337,425
Asset management and service fees		406,438		395,369
Other		7,530		7,514
Total revenue from contracts with customers		1,075,855		1,072,985
Other sources of revenue:
Interest		379,011		292,155
Principal transactions		200,496		186,766
Other		18,184		4,916
Total revenues	$	1,673,546	$	1,556,822

Revenue from contracts with customers is recognized when, or as, we satisfy our performance obligations by transferring the promised services to the customers. A service is transferred to a customer when, or as, the customer obtains control of that service. A performance obligation may be satisfied over time or at a point in time. Revenue from a performance obligation satisfied over time is recognized by measuring our progress in satisfying the performance obligation in a manner that depicts the transfer of the services to the customer. Revenue from a performance obligation satisfied at a point in time is recognized at the point in time that we determine the customer obtains control over the promised service. The amount of revenue recognized reflects the consideration we expect to be entitled to in exchange for those promised services (i.e., the “transaction price”). In determining the transaction price, we consider multiple factors, including the effects of variable consideration. Variable consideration is included in the transaction price only to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainties with respect to the amount are resolved. In determining when to include variable consideration in the transaction price, we consider the range of possible outcomes, the predictive value of our past experiences, the time period of when uncertainties expect to be resolved and the amount of consideration that is susceptible to factors outside of our influence, such as market volatility or the judgment and actions of third parties.

The following provides detailed information on the recognition of our revenues from contracts with customers:

Commissions. We earn commission revenue by executing, settling, and clearing transactions for clients primarily in OTC and listed equity securities, insurance products, and options. Trade execution and clearing and custody services, when provided together, represent a single performance obligation as the services are not separately identifiable in the context of the contract. Commission revenues associated with combined trade execution and clearing and custody services, as well as trade execution services on a standalone basis, are recognized at a point in time on trade-date. Commission revenues are generally paid on settlement date and we record a receivable between trade-date and payment on settlement date.

Investment Banking. We provide our clients with a full range of capital markets and financial advisory services. Capital markets services include underwriting and placement agent services in both the equity and debt capital markets, including private equity placements, initial public offerings, follow-on offerings, underwriting and distributing public and private debt.

Capital raising revenues are recognized at a point in time on trade-date, as the client obtains the control and benefit of the capital markets offering at that point. Costs associated with capital raising transactions are deferred until the related revenue is recognized or the engagement is otherwise concluded, and are recorded on a gross basis within other operating expenses in the consolidated statements of operations as we are acting as a principal in the arrangement. Any expenses reimbursed by our clients are recognized as investment banking revenues.

Revenues from financial advisory services primarily consist of fees generated in connection with merger, acquisition and restructuring transactions. Advisory fees from mergers and acquisitions engagements are recognized at a point in time when the related transaction is completed, as the performance obligation is to successfully broker a specific transaction. Fees received prior to the completion of the transaction are deferred within accounts payable and accrued expenses on the consolidated statements of financial condition. Advisory fees from restructuring engagements are recognized over time using a time elapsed measure of progress as our clients simultaneously receive and consume the benefits of those services as they are provided. A significant portion of the fees we receive for our advisory services are considered variable as they are contingent upon a future event (e.g., completion of a transaction or third party emergence from bankruptcy) and are excluded from the transaction price until the uncertainty associated with the variable consideration is subsequently resolved, which is expected to occur upon achievement of the specified milestone. Payment for advisory services are generally due promptly upon completion of a specified milestone or, for retainer fees, periodically over the course of the engagement. We recognize a receivable between the date of completion of the milestone and payment by the customer. Expenses associated with investment banking advisory engagements are deferred only to the extent they are explicitly reimbursable by the client and the related revenue is recognized at the same time as the associated expense. All other investment banking advisory related expenses, including expenses incurred related to restructuring assignments, are expensed as incurred. All investment banking advisory expenses are recognized within other operating expenses on the consolidated statements of operations and any expenses reimbursed by our clients are recognized as investment banking revenues.

Asset Management Fees. We earn management and performance fees in connection with investment advisory services provided to institutional and individual clients. Investment advisory fees are charged based on the value of assets in fee-based accounts and are affected by changes in the balances of client assets due to market fluctuations and levels of net new client assets. Fees are charged either in advance based on fixed rates applied to the value of the customers’ account at the beginning of the period or periodically based on contracted rates and account performance. Contracts can be terminated at any time with no incremental payments due to our company upon termination. If the contract is terminated by the customer fees are prorated for the period and fees charged for the post termination period are refundable to the customer.

The following tables present the Company’s revenues from contracts with customers by reportable segment disaggregated by major business activity and primary geographic regions for the three and six months ended June 30, 2019 and 2018 (in thousands):

	Three Months Ended June 30, 2019⁽¹⁾
	Global Wealth Management		Institutional Group		Other		Total
Major business activity:
Commissions	$	120,284	$	44,697	$	—	$	164,981
Capital raising ⁽¹⁾		10,559		86,153		—		96,712
Advisory fees ⁽¹⁾		—		82,905		—		82,905
Investment banking		10,559		169,058		—		179,617
Asset management		211,156		15		—		211,171
Other		3,549		—		199		3,748
Total		345,548		213,770		199		559,517
Primary Geographic Region:
United States		345,548		172,958		199		518,705
United Kingdom		—		39,668		—		39,668
Other		—		1,144		—		1,144
	$	345,548	$	213,770	$	199	$	559,517

	Three Months Ended June 30, 2018⁽¹⁾
	Global Wealth Management		Institutional Group		Other		Total
Major business activity:
Commissions	$	118,129	$	48,773	$	—	$	166,902
Capital raising ⁽¹⁾		7,968		66,112		—		74,080
Advisory fees ⁽¹⁾		81		86,922		—		87,003
Investment banking		8,049		153,034		—		161,083
Asset management		199,557		11		—		199,568
Other		2,907		—		889		3,796
Total		328,642		201,818		889		531,349
Primary Geographic Region:
United States		328,642		173,415		889		502,946
United Kingdom		—		25,953		—		25,953
Other		—		2,450		—		2,450
	$	328,642	$	201,818	$	889	$	531,349

⁽¹⁾ Excludes revenues not derived from contracts with customers included in the Other segment.

	Six Months Ended June 30, 2019⁽¹⁾
	Global Wealth Management		Institutional Group		Other		Total
Major business activity:
Commissions	$	230,211	$	90,219	$	—	$	320,430
Capital raising ⁽¹⁾		18,782		134,875		—		153,657
Advisory fees ⁽¹⁾		—		187,800		—		187,800
Investment banking		18,782		322,675		—		341,457
Asset management		406,409		29		—		406,438
Other		6,004		—		1,526		7,530
Total		661,406		412,923		1,526		1,075,855
Primary Geographic Region:
United States		661,406		349,698		1,526		1,012,630
United Kingdom		—		60,771		—		60,771
Other		—		2,454		—		2,454
	$	661,406	$	412,923	$	1,526	$	1,075,855

	Six Months Ended June 30, 2018⁽¹⁾
	Global Wealth Management		Institutional Group		Other		Total
Major business activity:
Commissions	$	237,334	$	95,343	$	—	$	332,677
Capital raising ⁽¹⁾		15,656		137,113		—		152,769
Advisory fees ⁽¹⁾		81		184,595		—		184,676
Investment banking		15,737		321,708		—		337,445
Asset management		395,346		23		—		395,369
Other		5,593		—		1,921		7,514
Total		654,010		417,074		1,921		1,073,005
Primary Geographic Region:
United States		654,010		349,765		1,921		1,005,696
United Kingdom		—		63,832		—		63,832
Other		—		3,477		—		3,477
	$	654,010	$	417,074	$	1,921	$	1,073,005

⁽¹⁾Excludes revenues not derived from contracts with customers included in the Other segment.

Information on Remaining Performance Obligations and Revenue Recognized from Past Performance

We do not disclose information about remaining performance obligations pertaining to contracts that have an original expected duration of one year or less. The transaction price allocated to remaining unsatisfied or partially unsatisfied performance obligations with an original expected duration exceeding one year was not material at June 30, 2019. Investment banking advisory fees that are contingent upon completion of a specific milestone and fees associated with certain distribution services are also excluded as the fees are considered variable and not included in the transaction price at June 30, 2019.

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

We had receivables related to revenues from contracts with customers of $142.5 million and $116.7 million at June 30, 2019 and December 31, 2018, respectively. We had no significant impairments related to these receivables during the six months ended June 30, 2019.

Our deferred revenue primarily relates to retainer fees received in investment banking advisory engagements and investment advisory fees where the performance obligation has not yet been satisfied. Deferred revenue at June 30, 2019 and December 31, 2018 was $16.7 million and $11.1 million, respectively.