Earnings Per Common Share [Line Items]

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- Definition

Earnings Per Share Basic And Diluted Numerator [Abstract]

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- Definition

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

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

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Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

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Number of additional shares included in diluted EPS for potentially dilutive effect of nonvested equity-based payment award containing forfeitable rights to dividends or dividend equivalents, whether paid or unpaid.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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.

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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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Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Aug. 20, 2018
Earnings Per Common Share [Line Items]
Conversion price (in dollars per share)	$ 101.38				$ 101.38
Numerator — basic and diluted
Net income	$ 64,598	$ 62,645	$ 43,609	$ 38,945	$ 127,243	$ 82,554
Denominator
Weighted average number of common shares outstanding — basic (in shares)	36,960		37,001		36,970	36,851
Effect of dilutive stock options (in shares)	459		558		445	430
Effect of dilutive restricted shares (in shares)	749		712		778	661
Weighted average number of common shares outstanding — diluted (in shares)	38,168		38,271		38,193	37,942
Earnings per common share — basic (in dollars per share)	$ 1.75		$ 1.18		$ 3.44	$ 2.24
Earnings per common share — diluted (in dollars per share)	$ 1.69		$ 1.14		$ 3.33	$ 2.18
Stock Options And Restricted Shares
Denominator
Antidilutive stock options and restricted shares (in shares)	25		44		38	330
Senior Notes \| Convertible Note Due 2023
Earnings Per Common Share [Line Items]
Interest rate (as a percent)	2.00%				2.00%
Conversion price (in dollars per share)							$ 101.38