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Acquisitions Purchase Price Allocation Table (Details) $ in Thousands, $ in Millions			6 Months Ended
	Feb. 25, 2019 USD ($)	Feb. 25, 2019 CAD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Goodwill	$ 78,800		$ 338,931	$ 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			29,330
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			328,497
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles			115,068
Goodwill			81,266
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets			556,977
Payments to Acquire Businesses, Gross	$ 490,800	$ 645.6	491,487
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities			32,169
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities			33,321
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities			65,490
Business Combination, Consideration Transferred			$ 556,977