Common Equity Common Equity 6 (Details)	6 Months Ended
	Jun. 30, 2015
Dividend Payment Restrictions [Line Items]
Maximum debt to capitalization ratio required to be maintained (as a percent)	65.00%
PGL
Dividend Payment Restrictions [Line Items]
Maximum debt to capitalization ratio required to be maintained (as a percent)	65.00%
WPS [Member]
Dividend Payment Restrictions [Line Items]
Maximum debt to capitalization ratio required to be maintained (as a percent)	65.00%
WPS [Member] | Maximum [Member] | Public Service Commission of Wisconsin [Member]
Dividend Payment Restrictions [Line Items]
Percentage of previous period's dividend as restriction on current period dividends	103.00%
WPS [Member] | Minimum [Member]
Dividend Payment Restrictions [Line Items]
Percentage of common stockholders' equity to total capitalization required to be maintained	25.00%
WPS [Member] | Minimum [Member] | Public Service Commission of Wisconsin [Member]
Dividend Payment Restrictions [Line Items]
Common equity ratio required to be maintained (as a percent)	51.00%