Earnings Per Share (Details) - $ / shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Reconciliation of Weighted-Average Diluted Shares Outstanding
Weighted average common shares outstanding - basic	66,182,000	65,957,000
Pro Forma Weighted Average Shares Outstanding, Diluted	66,182,000	65,957,000
Anti-dilutive Effect
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,197,000	689,000
Convertible Senior Note
Convertible Note, Shares To Be Received Upon Conversion (in thousands)	2,300,000
Convertible Note, Conversion Price	$ 85.39
Restricted stock
Anti-dilutive Effect
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	895,000	613,000
Other equity-based awards
Anti-dilutive Effect
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	302,000	76,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The price per share of the conversion feature embedded in the debt instrument.

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The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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The weighted average number of shares or units and dilutive common stock or unit equivalents outstanding in the calculation of proforma diluted earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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