Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- 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.

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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Long Term Debt (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Long Term Debt (Details) - USD ($) $ in Millions	Feb. 29, 2016	Mar. 31, 2016	Feb. 01, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Common Stock, Value, Issued		$ 3.2		$ 3.2
Integrys
Debt Instrument [Line Items]
Common Stock, Value, Issued			$ 66.4
Integrys \| TEG Junior Subordinated Notes, 6.11% due 2066 [Member]
Debt Instrument [Line Items]
Retirement of long-term debt	$ 154.9
Interest rate on long-term debt			6.11%
Debt Instrument, Repurchase Amount			$ 128.6
Long-term Debt, Gross		$ 114.9
Debt Instrument, Basis Spread on Variable Rate		2.12%