Variable Interest Entity - Summary of Assets and Liabilities at Carrying Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 130,519	$ 85,901
Other current assets	28,935	15,338
Property, plant, and equipment	934,843	942,703
Intangible assets, less accumulated amortization of $366,001 and $330,070	260,965	294,734
Long-term operating lease assets, net	97,051	84,042
Other long-term assets	20,818	21,770
Total assets	2,654,608	2,460,957
Current portion of long-term debt	68,694	72,347
Current liabilities	533,783	433,087
Long-term debt	887,266	937,863
Deferred income taxes	128,910	125,559
Long-term operating lease liabilities	78,617	67,898
Total liabilities	1,806,604	1,811,955
KFPC
Variable Interest Entity [Line Items]
Cash and cash equivalents	9,890	3,097
Other current assets	14,814	17,304
Property, plant, and equipment	142,790	150,838
Intangible assets, less accumulated amortization of $366,001 and $330,070	7,355	7,959
Long-term operating lease assets, net	6,938	7,178
Other long-term assets	2,683	6,510
Total assets	184,470	192,886
Current portion of long-term debt	67,726	72,156
Current liabilities	8,273	5,209
Long-term debt	0	17,559
Deferred income taxes	675	1,984
Long-term operating lease liabilities	6,445	6,700
Total liabilities	$ 83,119	$ 103,608