Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the period for which the minimum ratio of consolidated adjusted earnings before interest, taxes, depreciation and amortization to interest expense is required to be maintained under financial covenants.

+ References

No definition available.

+ Details

Name:	wdr_DebtInstrumentCovenantComplianceConsolidatedInterestCoverageMinimumRatioConsecutiveQuartersNumber
Namespace Prefix:	wdr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the period for which the maximum ratio of consolidated total debt to consolidated adjusted earnings before, interest, taxes, depreciation and amortization is required to be maintained under financial covenants.

+ References

No definition available.

+ Details

Name:	wdr_DebtInstrumentCovenantComplianceConsolidatedLeverageMaximumRatioConsecutiveQuartersNumber
Namespace Prefix:	wdr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the ratio of consolidated adjusted earnings before interest, taxes, depreciation and amortization to interest expense necessary to be maintained under the terms of the senior credit facilities' covenants.

+ References

No definition available.

+ Details

Name:	wdr_DebtInstrumentCovenantConsolidatedInterestCoverageRatio
Namespace Prefix:	wdr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the ratio of consolidated total debt to consolidated adjusted earnings before, interest, taxes, depreciation and amortization allowed under the terms of the senior credit facilities' covenants.

+ References

No definition available.

+ Details

Name:	wdr_DebtInstrumentCovenantConsolidatedLeverageRatio
Namespace Prefix:	wdr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the amount that the borrowing capacity under the credit facility can be expanded to at the option of lenders upon the entity's request.

+ References

No definition available.

+ Details

Name:	wdr_LineOfCreditFacilityAmountUptoWhichBorrowingCapacityCanBeExpanded
Namespace Prefix:	wdr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the term of the credit facility.

+ References

No definition available.

+ Details

Name:	wdr_LineOfCreditFacilityTerm
Namespace Prefix:	wdr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
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Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
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- Details

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- Details

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Indebtedness (Details) $ in Thousands			12 Months Ended
Indebtedness (Details) $ in Thousands	Jan. 13, 2018 USD ($)	Oct. 20, 2017 USD ($)	Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($)	Aug. 31, 2010 USD ($)
Indebtedness
Repayment of short-term debt				$ 94,925
Long-term debt			$ 94,926	94,854
Credit Facility
Indebtedness
Revolving credit facility term		3 years
Maximum borrowing capacity		$ 100,000
Amount that borrowing capacity can be expanded upon entity's request		$ 200,000
Borrowing outstanding under the facility			$ 0	$ 0
Senior Notes
Indebtedness
Face amount of notes issued and sold					$ 190,000
Consolidated leverage ratio			0.4
Number of consecutive quarters for which the maximum consolidated leverage ratio is required to be maintained under financial covenants \| item			4
Number of consecutive quarters for which the minimum consolidated interest coverage ratio is required to be maintained under financial covenants \| item			4
Consolidated interest coverage ratio			36.6
Senior Notes \| Maximum
Indebtedness
Consolidated leverage ratio			3.0
Senior Notes \| Minimum
Indebtedness
Consolidated interest coverage ratio			4.0
Senior 5.0% unsecured notes due, 2018 ("Series A Notes")
Indebtedness
Repayment of short-term debt	$ 95,000
Senior 5.75% unsecured notes due, 2021 ("Series B Notes")
Indebtedness
Fair value of outstanding long-term indebtedness			$ 98,000
Long-term debt			$ 94,900