14. Commitments: The company’s extended lines of credit to third-party entities include unused amounts of $8,537 million and $8,111 million at September 30, 2018 and December 31, 2017, respectively. A portion of these amounts was available to the company’s business partners to support their working capital needs. In addition, the company has committed to provide future financing to its clients in connection with client purchase agreements for approximately $3,798 million and $3,569 million at September 30, 2018 and December 31, 2017, respectively.

The company has applied the guidance requiring a guarantor to disclose certain types of guarantees, even if the likelihood of requiring the guarantor’s performance is remote. The following is a description of arrangements in which the company is the guarantor.

The company is a party to a variety of agreements pursuant to which it may be obligated to indemnify the other party with respect to certain matters. Typically, these obligations arise in the context of contracts entered into by the company, under which the company customarily agrees to hold the party harmless against losses arising from a breach of representations and covenants related to such matters as title to the assets sold, certain intellectual property (IP) rights, specified environmental matters, third-party performance of nonfinancial contractual obligations and certain income taxes. In each of these circumstances, payment by the company is conditioned on the other party making a claim pursuant to the procedures specified in the particular contract, the procedures of which typically allow the company to challenge the other party’s claims. While typically indemnification provisions do not include a contractual maximum on the company’s payment, the company’s obligations under these agreements may be limited in terms of time and/or nature of claim, and in some instances, the company may have recourse against third parties for certain payments made by the company.

It is not possible to predict the maximum potential amount of future payments under these or similar agreements due to the conditional nature of the company’s obligations and the unique facts and circumstances involved in each particular agreement. Historically, payments made by the company under these agreements have not had a material effect on the company’s business, financial condition or results of operations.

In addition, the company guarantees certain loans and financial commitments. The maximum potential future payment under these financial guarantees was $15 million and $19 million at September 30, 2018 and December 31, 2017, respectively. The fair value of the guarantees recognized in the Consolidated Statement of Financial Position is not material.

Changes in the company’s warranty liability for standard warranties and deferred income for extended warranty are presented in the following tables.

Standard Warranty Liability

(Dollars in millions)	2018			2017
Balance at January 1	$	152		$	156
Current period accruals	84			107
Accrual adjustments to reflect actual experience	(31		)	(3		)
Charges incurred	(93		)	(126		)

Balance at September 30	$	112		$	134

Extended Warranty Liability

(Dollars in millions)	2018			2017
Aggregate deferred revenue at January 1	$	566		$	531
Revenue deferred for new extended warranty contracts	138			175
Amortization of deferred revenue	(178		)	(198		)
Other*	(12		)	24

Aggregate deferred revenue at September 30	$	514		$	533

Current portion	$	242		$	258
Noncurrent portion	$	273		$	275

* Other primarily consists of foreign currency translation adjustments.