Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash paid during the period for:
Interest, including interest related to finance leases	$ 118,851	$ 118,974	$ 107,021
Income taxes, net	41,372	44,184	26,529
Non-cash investing and financing activities:
Issuance of stock dividend	0	703	671
Decrease in non-controlling interest related to purchase of subsidiary	0	0	(73,953)
Notes payable issued for purchase of subsidiary	0	0	30,000
Contingent consideration related to purchase of subsidiary	0	0	6,304
Net receivable from purchase of subsidiary	$ 0	$ 0	$ 497

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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