Schedule II - Valuation and Qualifying Accounts (Details Textual) - USD ($)	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Accounts Receivable, Credit Loss Expense (Reversal)	$ 53,239	$ 15,673
Cash Discounts Allowed on Sales and Charged Against Revenue	624,413	750,059
Accounts Receivable, Allowance for Credit Loss, Writeoff	0	7,547
Cash Discount on Sales	$ 624,413	$ 750,059

Represents the amount of cash discount on sales.

No definition available.

Name:	frd_CashDiscountOnSales
Namespace Prefix:	frd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of cash discount allowed on sales and charged against revenue.

+ References

No definition available.

+ Details

Name:	frd_CashDiscountsAllowedOnSalesAndChargedAgainstRevenue
Namespace Prefix:	frd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

+ Details

Name:	us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(5))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

Name:	us-gaap_ProvisionForDoubtfulAccounts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration