. Product Warranty Obligations

The Company records a liability for product warranty obligations at the time of sale to a customer based upon historical warranty experience. The Company also records a liability for specific warranty matters when they become known and are reasonably estimable. Additionally, the Company sells extended warranty coverage for certain products. The sales of extended warranties are recorded as deferred revenue, which is recognized over the life of the contracts.

The following is a tabular reconciliation of the product warranty liability, excluding the deferred revenue related to extended warranty coverage:

	Three Months E nded June 30 ,						Six Months Ended June 30,
	201 6			201 5			2016			2015

Balance at beginning of period	$	31,904		$	29,277		$	30,197		$	30,909
Product warranty reserve assumed in acquisition		-			-			840			-
Payments		(4,900	)		(5,100	)		(8,552	)		(10,533	)
Provision for warranties issued		4,220			4,480			7,702			9,029
Changes in estimates for pre-existing warranties		(489	)		(472	)		548			(1,220	)
Balance at end of period	$	30,735		$	28,185		$	30,735		$	28,185

The following is a tabular reconciliation of the deferred revenue related to extended warranty coverage:

	Three Months E nded June 30 ,						Six Months Ended June 30,
	201 6			201 5			2016			2015

Balance at beginning of period	$	28,830		$	27,531		$	28,961		$	27,193
Deferred revenue on extended warranty contracts sold		1,619			810			2,763			2,190
Amortization of deferred revenue on extended warranty contracts		(1,367	)		(1,100	)		(2,642	)		(2,142	)
Balance at end of period	$	29,082		$	27,241		$	29,082		$	27,241

Product warranty obligations and extended warranty related deferred revenues are included in the condensed consolidated balance sheets as follows:

	June 30 ,		December 31,
	201 6		201 5
Product warranty liability
Current portion - other accrued liabilities	$	21,071	$	21,726
Long-term portion - other long-term liabilities		9,664		8,471
Total	$	30,735	$	30,197

Deferred revenue related to extended warranty
Current portion - other accrued liabilities	$	5,034	$	6,026
Long-term portion - other long-term liabilities		24,048		22,935
Total	$	29,082	$	28,961