Commitments And Contingencies [Line Items]

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- Definition

Common Stock, Additional Voting Stock Ownership Percent That May Awarded

+ References

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- Definition

Common Stock, Shares Held in Estate

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- Definition

Common Stock, Voting Stock Ownership Percent

+ References

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- Definition

Insurance, Coverage Limit

+ References

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- Definition

Litigation Settlement Interest, Percent

+ References

No definition available.

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- Definition

Amount awarded from other party in judgment or settlement of litigation.

+ References

No definition available.

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- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

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Commitments And Contingencies (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2016	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Aug. 03, 2016	May 31, 2016
Cotter, Jr. Related Litigation Matters [Member]
Commitments And Contingencies [Line Items]
Amount of damages claimed by plaintiff		$ 1,200,000
Litigation expense		1,400,000	$ 645,000	$ 4,000,000
Coverage limit		$ 10,000,000
The STOMP Arbitration [Member]
Commitments And Contingencies [Line Items]
Settlement awarded	$ 2,300,000
Litigation interest percent	4.00%
Class B [Member] \| Cotter, Jr. Related Litigation Matters [Member]
Commitments And Contingencies [Line Items]
Shares held by estate					100,000
Class B [Member] \| Cotter Estate [Member] \| Cotter, Jr. Related Litigation Matters [Member]
Commitments And Contingencies [Line Items]
Shares held by estate		427,808				327,808
Class B [Member] \| Cotter Estate [Member] \| Cotter, Jr. Related Litigation Matters [Member] \| Maximum [Member]
Commitments And Contingencies [Line Items]
Additional voting stock that may be awarded		25.50%
Class B [Member] \| Cotter Trust [Member] \| Cotter, Jr. Related Litigation Matters [Member]
Commitments And Contingencies [Line Items]
Shares held by estate		696,080				696,080
Voting stock percent		41.40%