Summary of significant accounting policies.

No definition available.

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- Definition

Description of a prior period adjustment to previously issued financial statements, including an adjustment that is a correction of an error. At a minimum, the description may include the nature and reasons for the adjustment and the periods affected by the adjustment, as well as (1) the effect of the correction on each financial statement line item and any per-share amounts affected for each prior period presented (2) the cumulative effect of the change on retained earnings or other appropriate components of equity or net assets in the statement of financial position, as of the beginning of the earliest period presented, and (3) the effect of the prior period adjustment (both gross and net of applicable income tax) on the net income of each prior period presented in the entity's annual report for the year in which the adjustments are made.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22644-107794

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- Definition

Amount of increase (decrease) in current liabilities classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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- Definition

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3521-108585

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

+ References

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Quarterly Selected Financial Data (as Restated) (Unaudited) - Correction of Immaterial Errors - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended	12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Mar. 19, 2019	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Decrease in net cash provided by (used in) financing activities			$ (4,529)	$ 694,830	$ 68,547	$ (20,557)
Increase in net cash (used in) provided by operating activities			(517)	(679,362)	(2,132)	(4,983)
Increase in other current liabilities			$ (288)	$ 317	$ (139)	$ 499
Correction of Immaterial Errors [Member]
Summary Of Significant Accounting Policies [Line Items]
Decrease in net cash provided by (used in) financing activities	$ 2,400	$ 2,400
Increase in net cash (used in) provided by operating activities	2,400	2,400
Increase in other current liabilities	$ 2,400	$ 2,400
Error corrections and prior period adjustments, description					In connection with our preparation of the condensed consolidated financial statements for the third quarter of 2020, the Company determined that the dividend declared on common stock in November 2019 and paid in February 2020 was originally presented within the change in other current liabilities in the operating activities section of the unaudited consolidated statement of cash flows for the three and six-month periods ended March 31, 2020 and June 30, 2020, but should have been classified as a cash outflow within financing activities. The effect of correcting such classification error for the respective previously reported interim periods resulted in a $2.4 million decrease in net cash provided by (used in) financing activities and a $2.4 million increase in net cash (used in) provided by operating activities (specifically, to increase by $2.4 million the change in other current liabilities)