We conduct our business in two segments: 1) the Wholesale segment and 2) the Retail segment. The Wholesale segment includes the wholesale distribution of motor fuel to lessee dealers, independent dealers, commission agents, DMS, Circle K and through September 2019, company operated retail sites. We have exclusive motor fuel distribution contracts with lessee dealers who lease the property from us. We also have exclusive distribution contracts with independent dealers to distribute motor fuel but do not collect rent from the independent dealers. Similar to lessee dealers, we have motor fuel distribution agreements with DMS and Circle K and collect rent from both. The Retail segment includes the retail sale of motor fuel at retail sites operated by commission agents and through September 2019, the sale of convenience merchandise items and the retail sale of motor fuel at company operated sites. A commission agent is a retail site where we retain title to the motor fuel inventory and sell it directly to our end user customers. At commission agent retail sites, we manage motor fuel inventory pricing and retain the gross profit on motor fuel sales, less a commission to the agent who operates the retail site. Similar to our Wholesale segment, we also generate revenues through leasing or subleasing real estate in our Retail segment.

Unallocated items consist primarily of general and administrative expenses, depreciation, amortization and accretion expense, gains on dispositions and lease terminations, net, and the elimination of the Retail segment’s intersegment cost of revenues from motor fuel sales against the Wholesale segment’s intersegment revenues from motor fuel sales. The profit in ending inventory generated by the intersegment motor fuel sales is also eliminated. Total assets by segment are not presented as management does not currently assess performance or allocate resources based on that data.

The following table reflects activity related to our reportable segments (in thousands):

	Wholesale		Retail		Unallocated			Consolidated
Three Months Ended March 31, 2020
Revenues from fuel sales to external customers	$	302,123	$	65,769	$	—		$	367,892
Intersegment revenues from fuel sales		47,906		—		(47,906	)		—
Rent income		20,468		2,220		—			22,688
Other revenue		1,115		—		—			1,115
Total revenues	$	371,612	$	67,989	$	(47,906	)	$	391,695

Income from CST Fuel Supply equity interests	$	3,202	$	—	$	—		$	3,202
Operating income	$	29,265	$	395	$	47,772		$	77,432

Three Months Ended March 31, 2019
Revenues from fuel sales to external customers	$	329,913	$	99,600	$	—		$	429,513
Intersegment revenues from fuel sales		75,881		—		(75,881	)		—
Revenues from food and merchandise sales		—		20,016		—			20,016
Rent income		19,636		2,002		—			21,638
Other revenue		619		—		—			619
Total revenues	$	426,049	$	121,618	$	(75,881	)	$	471,786

Income from CST Fuel Supply equity interests	$	3,426	$	—	$	—		$	3,426
Operating income (loss)	$	24,288	$	608	$	(17,284	)	$	7,612

From the dealerization of the 46 company operated sites in the third quarter of 2019 through March 31, 2020, we did not have any company operated sites. See Note 4 for information related to the acquisition of retail and wholesale assets.

Receivables relating to the revenue streams above are as follows (in thousands):

Performance obligations are satisfied as fuel is delivered to the customer. Many of our contracts with our customers include minimum purchase volumes measured on a monthly basis, although such revenue is not material. Receivables from fuel are recognized on a per-gallon rate and are generally collected within 10 days of delivery.

The balance of unamortized costs incurred to obtain certain contracts with customers was $6.7 million and $6.5 million at March 31, 2020 and December 31, 2019, respectively. Amortization of such costs is recorded against operating revenues and amounted to $0.3 million for the three months ended March 31, 2020 and $0.2 million for the three months ended March 31, 2019.

Receivables from rent and other lease-related charges are generally collected at the beginning of the month.