Debt (5.875% Senior Notes) (Details) - 5.875% Senior Notes due 2022 - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Oct. 03, 2013
Debt Instrument [Line Items]
Stated interest rate	5.875%	5.875%
Senior Notes
Debt Instrument [Line Items]
Stated interest rate	5.875%	5.875%
Debt instrument, face amount			$ 250,000,000.0
Debt instrument, coupon rate	5.875%
Debt instrument, yield to maturity	5.875%
Debt instrument, payment terms	Interest on the 5.875% Senior Notes due 2022 was payable semi-annually in cash in arrears on January 15 and July 15, commencing on January 15, 2014.
Debt instrument, frequency of payment	semi-annually
Debt instrument, commencement date of first required payment	Jan. 15, 2014
Debt instrument, maturity date	Jan. 15, 2022

Debt instrument coupon rate.

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- Definition

Debt instrument yield to maturity percentage.

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- Definition

Date the debt agreement requires the first payment to be made, in YYYY-MM-DD format.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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