Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parentheticals) - $ / shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Common stock dividends declared, per common share (in dollars per share)	$ 0.00875	$ 0.0025
Preferred stock dividends declared, per share (in dollars per share)	$ 0.875	$ 0.875
Common stock issued for 401(k) match, shares (in shares)	165,000	352,000
Shares issued to pension plans, shares (in shares)	3,500,000

The number of shares of stock issued during period for a 401k match.

No definition available.

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Namespace Prefix:	hl_
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

+ Details

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- Definition

Aggregate dividends declared during the period for each share of preferred stock outstanding.

+ References

No definition available.

+ Details

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- Definition

Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration