The following table presents the Company’s revenues disaggregated by product classification and by operating segment, excluding sales taxes collected and remitted to governmental authorities.

	Three Months Ended				Six Months Ended
	March 31,				March 31,
(Dollars in thousands)	2020		2019		2020		2019
Medical Device
Product sales	$	5,455	$	4,558	$	10,477	$	9,336
Royalties		6,714		8,313		15,613		15,998
Research, development and other		2,628		2,811		4,862		5,195
License fees		1,507		1,619		2,756		4,030
Total Revenue — Medical Device		16,304		17,301		33,708		34,559
In Vitro Diagnostics
Product sales		6,315		5,329		11,267		10,302
Other		203		46		463		56
Total Revenue — In Vitro Diagnostics		6,518		5,375		11,730		10,358
Total Revenue	$	22,822	$	22,676	$	45,438	$	44,917

Contract asset balances consist of estimated sales-based royalties earned but not collected at each balance sheet date and are subject to timing fluctuations at the end of a given period. The Company’s deferred revenue, or contract liability, is primarily related to the upfront and milestone payments received pursuant to the collaborative license and commercialization agreement with Abbott Vascular, Inc. (the “Abbott Agreement”) for the Company’s SurVeil™ drug-coated balloon product (“SurVeil DCB”) discussed in Note 3.

As of March 31, 2020, the estimated revenue expected to be recognized in future periods related to performance obligations that are unsatisfied for executed contracts with an original duration of one year or more totaled approximately $14.3 million. These remaining performance obligations relate to the Abbott Agreement (Note 3), exclude contingent milestone payments under the Abbott Agreement, and are expected to be recognized over the next five years through fiscal 2025 as services, principally the TRANSCEND study, are completed.