Short-term Borrowings and Short-term Bank Lines of Credit	9 Months Ended
Sep. 30, 2013
Short-term Borrowings and Short-term Bank Lines of Credit [Abstract]
Short-term Borrowings and Short-term Bank Lines of Credit [Text Block]	7. SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT Great Plains Energy's $200 Million Revolving Credit Facility In October 2013, Great Plains Energy entered into an amendment to its $200 million revolving credit facility with a group of banks to extend the term to October 2018 from December 2016. The facility's terms permit transfers of unused commitments between this facility and the KCP&L and GMO facilities discussed below, with the total amount of the facility not exceeding $400 million at any one time. A default by Great Plains Energy or any of its significant subsidiaries on other indebtedness totaling more than $50.0 million is a default under the facility. Under the terms of this facility, Great Plains Energy is required to maintain a consolidated indebtedness to consolidated capitalization ratio, as defined in the facility, not greater than 0.65 to 1.00 at all times. At September 30, 2013, Great Plains Energy was in compliance with this covenant. At September 30, 2013, Great Plains Energy had $6.0 million of outstanding cash borrowings at a weighted-average interest rate of 1.94% and had issued letters of credit totaling $1.8 million under the credit facility. At December 31, 2012, Great Plains Energy had $12.0 million of outstanding cash borrowings at a weighted-average interest rate of 2.00% and had issued letters of credit totaling $1.8 million under the credit facility. KCP&L's $600 Million Revolving Credit Facility and Commercial Paper In October 2013, KCP&L entered into an amendment to its $600 million revolving credit facility with a group of banks that provides support for its issuance of commercial paper and other general corporate purposes to extend the term to October 2018 from December 2016. Great Plains Energy and KCP&L may transfer up to $200 million of unused commitments between Great Plains Energy's and KCP&L's facilities. A default by KCP&L on other indebtedness totaling more than $50.0 million is a default under the facility. Under the terms of this facility, KCP&L is required to maintain a consolidated indebtedness to consolidated capitalization ratio, as defined in the facility, not greater than 0.65 to 1.00 at all times. At September 30, 2013, KCP&L was in compliance with this covenant. At September 30, 2013, KCP&L had $23.7 million of commercial paper outstanding at a weighted-average interest rate of 0.27%, had issued letters of credit totaling $3.8 million and had no outstanding cash borrowings under the credit facility. At December 31, 2012, KCP&L had $361.0 million of commercial paper outstanding at a weighted-average interest rate of 0.48%, had issued letters of credit totaling $13.9 million and had no outstanding cash borrowings under the credit facility. GMO's $450 Million Revolving Credit Facility and Commercial Paper In October 2013, GMO entered into an amendment to its $450 million revolving credit facility with a group of banks that provides support for its issuance of commercial paper and other general corporate purposes to extend the term to October 2018 from December 2016. As part of the amendment, Great Plains Energy no longer guarantees GMO's obligations under the credit facility. Great Plains Energy and GMO may transfer up to $200 million of unused commitments between Great Plains Energy's and GMO's facilities. A default by GMO or any of its significant subsidiaries on other indebtedness totaling more than $50.0 million is a default under the facility. Under the terms of this facility, GMO is required to maintain a consolidated indebtedness to consolidated capitalization ratio, as defined in the facility, not greater than 0.65 to 1.00 at all times. At September 30, 2013, GMO was in compliance with this covenant. At September 30, 2013, GMO had $29.3 million of commercial paper outstanding at a weighted-average interest rate of 0.66%, had issued letters of credit totaling $14.6 million and had no outstanding cash borrowings under the credit facility. At December 31, 2012, GMO had $169.1 million of commercial paper outstanding at a weighted-average interest rate of 0.94%, had issued letters of credit totaling $15.1 million and had no outstanding cash borrowings under the credit facility.

7. SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT

Great Plains Energy's $200 Million Revolving Credit Facility

In October 2013, Great Plains Energy entered into an amendment to its $200 million revolving credit facility with a group of banks to extend the term to October 2018 from December 2016. The facility's terms permit transfers of unused commitments between this facility and the KCP&L and GMO facilities discussed below, with the total amount of the facility not exceeding $400 million at any one time. A default by Great Plains Energy or any of its significant subsidiaries on other indebtedness totaling more than $50.0 million is a default under the facility. Under the terms of this facility, Great Plains Energy is required to maintain a consolidated indebtedness to consolidated capitalization ratio, as defined in the facility, not greater than 0.65 to 1.00 at all times. At September 30, 2013, Great Plains Energy was in compliance with this covenant. At September 30, 2013, Great Plains Energy had $6.0 million of outstanding cash borrowings at a weighted-average interest rate of 1.94% and had issued letters of credit totaling $1.8 million under the credit facility. At December 31, 2012, Great Plains Energy had $12.0 million of outstanding cash borrowings at a weighted-average interest rate of 2.00% and had issued letters of credit totaling $1.8 million under the credit facility.

KCP&L's $600 Million Revolving Credit Facility and Commercial Paper

In October 2013, KCP&L entered into an amendment to its $600 million revolving credit facility with a group of banks that provides support for its issuance of commercial paper and other general corporate purposes to extend the term to October 2018 from December 2016. Great Plains Energy and KCP&L may transfer up to $200 million of unused commitments between Great Plains Energy's and KCP&L's facilities. A default by KCP&L on other indebtedness totaling more than $50.0 million is a default under the facility. Under the terms of this facility, KCP&L is required to maintain a consolidated indebtedness to consolidated capitalization ratio, as defined in the facility, not greater than 0.65 to 1.00 at all times. At September 30, 2013, KCP&L was in compliance with this covenant. At September 30, 2013, KCP&L had $23.7 million of commercial paper outstanding at a weighted-average interest rate of 0.27%, had issued letters of credit totaling $3.8 million and had no outstanding cash borrowings under the credit facility. At December 31, 2012, KCP&L had $361.0 million of commercial paper outstanding at a weighted-average interest rate of 0.48%, had issued letters of credit totaling $13.9 million and had no outstanding cash borrowings under the credit facility.

GMO's $450 Million Revolving Credit Facility and Commercial Paper

In October 2013, GMO entered into an amendment to its $450 million revolving credit facility with a group of banks that provides support for its issuance of commercial paper and other general corporate purposes to extend the term to October 2018 from December 2016. As part of the amendment, Great Plains Energy no longer guarantees GMO's obligations under the credit facility. Great Plains Energy and GMO may transfer up to $200 million of unused commitments between Great Plains Energy's and GMO's facilities. A default by GMO or any of its significant subsidiaries on other indebtedness totaling more than $50.0 million is a default under the facility. Under the terms of this facility, GMO is required to maintain a consolidated indebtedness to consolidated capitalization ratio, as defined in the facility, not greater than 0.65 to 1.00 at all times. At September 30, 2013, GMO was in compliance with this covenant. At September 30, 2013, GMO had $29.3 million of commercial paper outstanding at a weighted-average interest rate of 0.66%, had issued letters of credit totaling $14.6 million and had no outstanding cash borrowings under the credit facility. At December 31, 2012, GMO had $169.1 million of commercial paper outstanding at a weighted-average interest rate of 0.94%, had issued letters of credit totaling $15.1 million and had no outstanding cash borrowings under the credit facility.