Inventories

9 Months Ended

Sep. 30, 2019

Inventory Disclosure [Abstract]

Inventories

Inventories

	September 30, 2019		December 31, 2018
Raw materials	$	46,714	$	55,002
Work in progress	65,146		46,728
Finished goods	57,558		39,368
Spares and other	24,618		24,555
	194,036		165,653
Reduction to LIFO cost basis	(31,557)		(28,471)
Total inventories – net	$	162,479	$	137,182

The increase in Total inventories – net at September 30, 2019 compared to the balance at December 31, 2018 was due primarily to increased Work in progress and Finished goods inventory due to sales timing, product mix and buffer inventory build ahead of the Company's planned fourth quarter 2019 turnaround partially offset by lower levels of Raw materials driven by the timing of cumene deliveries.