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Summary of Significant Accounting Policies (Revised Consolidated Statements of Stockholders' Equity) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retained earnings, beginning of period	$ 137,478	$ 151,342
Balance, beginning of period	247,693	259,232
Net income	4,082	98
Retained earnings, end of period	141,560	151,440
Balance, end of period	$ 252,129	260,188
As Reported
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retained earnings, beginning of period		152,291
Balance, beginning of period		260,181
Net income		357
Retained earnings, end of period		152,648
Balance, end of period		261,396
Revisions | Revision Of Prior Period Financial Statements
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retained earnings, beginning of period		(949)
Balance, beginning of period		(949)
Net income		(259)
Retained earnings, end of period		(1,208)
Balance, end of period		$ (1,208)

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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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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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