Note

— Lease Obligations and Other Contingencies

The Company has the following minimum payments under operating lease obligations that existed at

December

31,

2018:

2019	$	1,300
2020		934
2021		524
2022		491
2023		503
Thereafter		1,495
Total minimum payments	$	5,247

The obligations in the preceding table are primarily related to the Company’s leases for buildings in Birmingham, Alabama and Durham, North Carolina. As of

December 31, 2018,

the lease for the Company’s headquarters in Durham, North Carolina expires

June

30,

2020,

but it was subsequently extended to

December 31, 2020.

The lease for the Company’s research facility in Birmingham, Alabama expires

October 31, 2026.

Rent expense for operating leases was

$758,

$617

and

$721

2018,

2017,

and

2016,

respectively.

Lease Financing Obligation

Based on the terms of the lease agreement for the new research facility in Birmingham, Alabama, the Company had construction period risks during the construction period and the Company was deemed the owner of the building (for accounting purposes only) during the construction period, which ended in

2016.

Accordingly, the Company recorded an asset of

$1,589

December 31, 2015,

representing the Company’s leased portion of the building and recorded a corresponding liability. Upon completion of leasehold improvement construction, the Company did

not

meet the sale-leaseback criteria for de-recognition of the building asset and liability. Therefore, the lease is accounted for as a financing obligation. The asset will be depreciated over the expected duration of the lease, and rental payments will be treated as principal and interest payments on the lease financing obligation liability. The underlying accounting for this transaction has

impact on cash flows associated with the underlying lease and or construction in process.

December 31, 2018

and

2017,

the lease financing obligation balance was

$2,703

and

$2,704,

respectively and was recorded as a long-term liability on the Consolidated Balance Sheets. The remaining future minimum payments under the lease financing obligation are

$3,890.