Earnings per common share (Details) - $ / shares shares in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Weighted average common shares outstanding - basic	200,440	196,401
Effect of dilutive performance share awards and restricted stock units	16	13
Weighted average common shares outstanding - diluted	200,456	196,414
Shares excluded from the calculation of diluted earnings per share	68	64
Dividends declared per common share	$ 0.2075	$ 0.2025

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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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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-Publisher FASB
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- References

No definition available.

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- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References

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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

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-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

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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