Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income taxes currently payable	$ 22,280	$ 10,317
Deferred income taxes	(1,586)	2,081
Provision for income taxes	$ 20,694	$ 12,398

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration