Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2020
Stock-Based Compensation [Abstract]
Weighted Average Number of Shares, Restricted Stock	98,917	75,262
Common Stock, Dividends, Per Share, Cash Paid				$ 7.00
Dividends, Common Stock, Cash			$ 216,529	$ 216,500
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Period Increase (Decrease)				23,655

Aggregate dividends paid during the period for each share of common stock outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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No definition available.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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- Definition

Increase (decrease) in the number of shares under non-option equity instrument agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Number of shares of restricted stock determined by relating the portion of time within a reporting period that restricted shares have been outstanding to the total time in that period. Restricted shares are subject to sales, contractual, regulatory or other restrictions that prevent or inhibit the holder from freely disposing of them before the restriction ends.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=121326447&loc=d3e2646-109256

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