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Equity-Based Compensation (Summary of Compensation Expense Connection with Awards) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized under the Prior Plan	$ 40	$ 192	$ 569
Expense recognized under the Non-Employee Directors Plan	760	570	444
Total stock compensation expense	8,173	12,570	9,189
Tax benefits recognized related to stock compensation expense	2,272	3,136	2,509
2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized under the Plan	1,932	5,077	7,988
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized under the Plan	$ 5,441	$ 6,731	$ 188

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Share-Based Goods and Nonemployee Services Transaction, Share-based Compensation

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Amount of noncash expense for share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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