Summary of Significant Accounting Policies - Acquisition (Details) - USD ($) $ in Thousands		12 Months Ended
Jul. 01, 2020	Dec. 31, 2020
Cash paid for acquisition		$ 8,392
Carthage Crushed Limestone
Ownership acquired (as a percent)	100.00%
Cash paid for acquisition	$ 8,400
Accounts receivable	1,100
Inventory	400
Property, plant and equipment	7,500
Accounts payable and other liabilities	$ 600
Revenue of business acquisition		$ 4,600

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date and other liabilities.

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No definition available.

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