18. Guarantees

The Company periodically enters into transactions with customers that provide for residual value guarantees and buyback commitments. These initial transactions are recorded as deferred revenue and are amortized to income on a straight-line basis over a period equal to that of the customer’s third-party financing agreement. The deferred revenue included in accounts payable and accrued expenses and non-current liabilities at December 31, 2017 and December 31, 2016 was $29.7 million and $30.4 million, respectively. The total amount of residual value guarantees and buyback commitments given by the Company and outstanding at December 31, 2017 and December 31, 2016 was $28.2 million and $32.8 million, respectively. These amounts are not reduced for amounts the Company would recover from repossessing and subsequent resale of the units. The residual value guarantees and buyback commitments expire at various times through 2019.

In the normal course of business, the Company provides its customers a warranty covering workmanship, and in some cases materials, on products manufactured by the Company. Such warranty generally provides that products will be free from defects for periods ranging from 12 months to 60 months. If a product fails to comply with the Company’s warranty, the Company may be obligated, at its expense, to correct any defect by repairing or replacing such defective products. The Company provides for an estimate of costs that may be incurred under its warranty at the time product revenue is recognized. These costs primarily include labor and materials, as necessary, associated with repair or replacement. The primary factors that affect the Company’s warranty liability include the number of units shipped and historical and anticipated warranty claims. As these factors are impacted by actual experience and future expectations, the Company assesses the adequacy of its recorded warranty liability and adjusts the amounts as necessary. Below is a table summarizing the warranty activity for the years ended December 31, 2017 and 2016:

(in millions)	2017			2016
Balance at beginning of period	$	28.6		$	32.4
Accruals for warranties issued during the period		34.6			20.4
Settlements made (in cash or in kind) during the period		(29.9	)		(23.7	)
Currency translation		1.9			(0.5	)
Balance at end of period	$	35.2		$	28.6