Revenues

The following table disaggregates our revenues by market (in thousands):



	Three Months Ended March 31, 2018
System One segment
Home	$	58,679
Critical Care	24,208
Total System One segment	82,887
In-Center segment	17,357
Other	2,820
Products subtotal	103,064
Services segment	5,419
Elimination of intersegment revenues	(1,185		)
Total	$	107,298

For the three months ended March 31, 2018, revenue recognized from performance obligations related to prior periods, including changes to variable consideration estimates, was not material.

Capitalized commission fees are amortized consistently with the pattern of transfer of the good to which the asset relates which is approximately 21 months. Capitalized commission fees were $2.1 million and $2.0 million as of March 31, 2018 and January 1, 2018, respectively, and are included in prepaid expenses and other current assets and other assets on our condensed consolidated balance sheet. During the three months ended March 31, 2018, we recorded $0.6 million of amortization expense related to capitalized commissions, which is included in sales and marketing expense, and there was no impairment loss in relation to the costs capitalized.

Long-term deferred revenues primary relate to sales of System One hardware to dialysis clinic customers in the home market made under the depot service model which is deemed to be a lease element of the respective home transactions and, to a lesser extent, deferred revenue related to our Dialyzer Production Agreement with Asahi which is recognized in revenues on a straight-line basis over the expected term of the agreement. Other revenue expected to be recognized in future years related to remaining performance obligations, excluding revenue pertaining to contracts that have an original expected duration of one year or less and contracts where revenue is recognized as invoiced, is immaterial.