In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842).” The purpose of this new guidance is to increase the transparency and comparability among organizations by recognizing lease assets and lease liabilities in the consolidated balance sheets as well as providing additional disclosure requirements related to leasing arrangements. The new guidance was effective for us beginning January 1, 2019, which we adopted using a modified retrospective method and the transition relief guidance provided by the FASB in ASU 2018-11 “Leases: Targeted Improvement”. Under this adoption method, we have not restated comparative prior periods and have carried forward the assessment of whether our contracts are or contain leases, the classification of our leases and the remaining lease terms. Based on our portfolio of leases at January 1, 2019, $21.6 million of lease assets and liabilities were recognized in our consolidated balance sheets, which related to operating leases for real estate. Under the transition relief guidance, we have elected the lease vs. non-lease components practical expedient relating to the asset class of real estate, the short-term lease exemption practical expedient and the package of practical expedients. In connection with the adoption of this standard, we updated our control framework and implemented changes to our existing controls to account for leases.

The Company’s leases primarily consist of noncancellable operating leases for office space with contractual terms expiring from 2020 to 2025. All of our leases are operating leases and, as a lessee, we have not entered into any sublease agreements. The lease term is defined as the fixed noncancellable term of the lease plus all periods, if any, for which failure to renew the lease imposes a penalty on us in an amount that appears, at the inception of the lease, to be reasonably assured. While some of our leases include an option to extend the lease up to five years, it is not reasonably certain that any such options will be exercised due, in part, to the dynamic nature of our sales force and rate of growth. Some of our leases contain termination options that are not reasonably certain to be exercised. However, if a termination option is exercised, we remeasure the lease asset in the consolidated balance sheets using the updated lease period. None of our leases contain residual value guarantees, substantial restrictions or covenants.

Lease assets of $27.1 million as of December 31, 2019 were included in Other assets in our consolidated balance sheets, which included a $1.5 million reduction to Other assets for deferred rent. When a lease contains a predetermined fixed escalation of the minimum rent, we recognize the related lease expense on a straight-line basis and record the difference between the lease expense and the amount payable under the lease as an adjustment to the right-of-use asset. Short-term lease liabilities of $10.3 million as of December 31, 2019 were included in Accrued expenses and other current liabilities in our consolidated balance sheets. In addition, long-term lease liabilities of $18.4 million as of December 31, 2019 were recognized in Other long-term liabilities in our consolidated balance sheets.

Rent expense under operating leases for the years ended December 31, 2019, 2018 and 2017 was $10.1 million, $7.6 million and $6.1 million, respectively. Cash paid for amounts relating to our operating leases was $11.8 million for the year ended December 31, 2019.

Because no implicit discount rates for our leases could be readily determined, we elected to use an estimated incremental borrowing rate to determine the present value of our leases. The weighted average discount rate related to our portfolio of leases at December 31, 2019 was 3.9%. The average remaining lease term for our leases was 2.8 years as of December 31, 2019.

The undiscounted cash flows for the future annual maturities of our operating lease liabilities and the reconciliation of those total undiscounted cash flows to our lease liabilities as of December 31, 2019 were as follows:

2020	$	10,462
2021		7,375
2022		6,071
2023		4,474
2024		2,063
Thereafter		301
Total undiscounted cash flows	$	30,746
Present value discount		(2,061	)
Lease liabilities	$	28,685

The table above does not include any legally binding minimum lease payments for leases signed but not yet commenced. As of December 31, 2019, the present value of the operating lease liabilities that had not yet commenced was $4.0 million.