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Acquisitions Purchase Price Allocation Table (Details) $ in Thousands, $ in Millions			9 Months Ended
	Feb. 25, 2019 USD ($)	Feb. 25, 2019 CAD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Goodwill	$ 78,800		$ 338,856	$ 257,302
Meritage ULC [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents			2,756
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables			29,040
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other			60
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			327,637
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles			115,068
Goodwill			82,099
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets			556,660
Payments to Acquire Businesses, Gross	$ 490,800	$ 645.6	491,487
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities			32,150
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities			33,023
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities			65,173
Business Combination, Consideration Transferred			$ 556,660