XML 169 R51.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Income Taxes (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Income Tax Disclosure [Abstract] |
Schedule Of Remeasurements Of Deferred Income Taxes Due To Tax Reform [Table Text Block] | The one-time impacts recorded by the Registrants to remeasure their deferred income tax balances at the 21% corporate federal income tax rate as of December 31, 2017 are presented below:
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon(b) |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Net Decrease to Deferred Income Tax Liability Balances | $8,624 |  | $1,895 |  | $2,819 |  | $1,407 |  | $1,120 |  | $1,944 |  | $968 |  | $540 |  | $456
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO(c) |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Net Regulatory Liability Recorded(a) | $7,315 |  | N/A |  | $2,818 |  | $1,394 |  | $1,124 |  | $1,979 |  | $976 |  | $545 |  | $458
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon(b) |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Net Deferred Income Tax Benefit/(Expense) Recorded | $1,309 |  | $1,895 |  | $1 |  | $13 |  | $(4) |  | $(35) |  | $(8) |  | $(5) |  | $(2)
__________
(a) | Reflects the net regulatory liabilities recorded on a pre-tax basis before taking into consideration the income tax benefits associated with the ultimate settlement with customers.
(b) | Amounts do not sum across due to deferred tax adjustments recorded at the Exelon Corporation parent company, primarily related to certain employee compensation plans.
(c) | Given the regulatory treatment of income tax benefits related to electric and gas distribution repairs, PECO remained in an overall net regulatory asset position as of December 31, 2017 after recording the impacts related to the TCJA.
ScheduleOfCategorizationOfNetRegulatoryLiabilitiesDueToTaxReform [Table Text Block] | The table below sets forth the Registrants’ estimated categorization of their net regulatory liabilities as of December 31, 2017. The amounts in the table below are shown on an after-tax basis reflecting future net cash outflows after taking into consideration the income tax benefits associated with the ultimate settlement with customers.
|  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | ComEd |  | PECO(a) |  | BGE |  | PHI |  | PEPCO |  | DPL |  | ACE
Subject to IRS Normalization Rules | $3,040 |  | $1,400 |  | $533 |  | $459 |  | $648 |  | $299 |  | $195 |  | $153
Subject to Rate Regulator Determination | 1,694 |  | 573 |  | 43 |  | 324 |  | 754 |  | 391 |  | 194 |  | 170 |
Net Regulatory Liabilities | $4,734 |  | $1,973 |  | $576 |  | $783 |  | $1,402 |  | $690 |  | $389 |  | $ | 323 |
_________
(a) | Given the regulatory treatment of income tax benefits related to electric and gas distribution repairs, PECO was in an overall net regulatory asset position as of December 31, 2017 after recording the impacts related to the TCJA. As a result, the amount of customer benefits resulting from the TCJA subject to the discretion of PECO's rate regulators are lower relative to the other Utility Registrants.
Schedule of Components of Income Tax Expense (Benefit) | Income tax expense (benefit) from continuing operations is comprised of the following components:
| For the Year Ended December 31, 2018 |  |
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Included in operations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | $ | 226 |  |  | $ | 337 |  |  | $ | (63 | ) |  | $ | 11 |  |  | $ | (5 | ) |  | $ | (4 | ) |  | $ | 28 |  |  | $ | (3 | ) |  | $ | (14 | )
Deferred | (98 | ) |  | (347 | ) |  | 145 |  |  | 10 |  |  | 47 |  |  | 24 |  |  | (21 | ) |  | 13 |  |  | 18 |
Investment tax credit amortization | (24 | ) |  | (21 | ) |  | (2 | ) |  | — |  |  | — |  |  | (1 | ) |  | — |  |  | — |  |  | — |
State |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | (1 | ) |  | 6 |  |  | (29 | ) |  | 1 |  |  | — |  |  | 7 |  |  | — |  |  | — |  |  | — |
Deferred | 17 |  |  | (83 | ) |  | 117 |  |  | (16 | ) |  | 32 |  |  | 9 |  |  | 6 |  |  | 12 |  |  | 8 |
Total | $ | 120 |  |  | $ | (108 | ) |  | $ | 168 |  |  | $ | 6 |  |  | $ | 74 |  |  | $ | 35 |  |  | $ | 13 |  |  | $ | 22 |  |  | $ | 12 |
| For the Year Ended December 31, 2017(a) |  |
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Included in operations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | $ | 194 |  |  | $ | 584 |  |  | $ | (191 | ) |  | $ | 71 |  |  | $ | 74 |  |  | $ | (60 | ) |  | $ | (20 | ) |  | $ | (24 | ) |  | $ | (12 | )
Deferred | (471 | ) |  | (2,005 | ) |  | 523 |  |  | 28 |  |  | 101 |  |  | 250 |  |  | 114 |  |  | 82 |  |  | 34 |
Investment tax credit amortization | (25 | ) |  | (21 | ) |  | (2 | ) |  | — |  |  | (1 | ) |  | (1 | ) |  | — |  |  | — |  |  | — |
State |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | 14 |  |  | 65 |  |  | (49 | ) |  | 14 |  |  | (5 | ) |  | (4 | ) |  | (2 | ) |  | — |  |  | — |
Deferred | 162 |  |  | 1 |  |  | 136 |  |  | (9 | ) |  | 49 |  |  | 32 |  |  | 13 |  |  | 13 |  |  | 4 |
Total | $ | (126 | ) |  | $ | (1,376 | ) |  | $ | 417 |  |  | $ | 104 |  |  | $ | 218 |  |  | $ | 217 |  |  | $ | 105 |  |  | $ | 71 |  |  | $ | 26 |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Successor |  |  | Predecessor
| For the Year Ended December 31, 2016(a) |  | March 24, 2016 to December 31, 2016 |  |  | January 1, 2016 to March 23, 2016
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | Pepco |  | DPL |  | ACE |  | PHI |  |  | PHI
Included in operations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | $ | 60 |  |  | $ | 513 |  |  | $ | (135 | ) |  | $ | 63 |  |  | $ | 51 |  |  | $ | (118 | ) |  | $ | (88 | ) |  | $ | (26 | ) |  | $ | (281 | ) |  |  | $ | — |
Deferred | 600 |  |  | (254 | ) |  | 379 |  |  | 72 |  |  | 88 |  |  | 136 |  |  | 97 |  |  | 22 |  |  | 283 |  |  |  | 10 |
Investment tax credit amortization | (24 | ) |  | (20 | ) |  | (2 | ) |  | — |  |  | (1 | ) |  | — |  |  | — |  |  | — |  |  | (1 | ) |  |  | — |
State |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current | 39 |  |  | 45 |  |  | (4 | ) |  | 9 |  |  | 5 |  |  | 7 |  |  | 1 |  |  | — |  |  | (11 | ) |  |  | — |
Deferred | 78 |  |  | (2 | ) |  | 63 |  |  | 5 |  |  | 31 |  |  | 16 |  |  | 12 |  |  | — |  |  | 13 |  |  |  | 7 |
Total | $ | 753 |  |  | $ | 282 |  |  | $ | 301 |  |  | $ | 149 |  |  | $ | 174 |  |  | $ | 41 |  |  | $ | 22 |  |  | $ | (4 | ) |  | $ | 3 |  |  |  | $ | 17 |
The following tables represent the net interest and penalties receivable (payable), including interest and penalties related to tax positions reflected in the Registrants’ Consolidated Balance Sheets.
Net interest receivable (payable) as of | Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
December 31, 2018 | $ | 236 |  |  | $ | (2 | ) |  | $ | 4 |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |
December 31, 2017 | 233 |  |  | (3 | ) |  | 4 |  |  | — |  |  | — |  |  | 2 |  |  | — |  |  | — |  |  | — |
Net penalties payable as of | Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
December 31, 2018 | $ | (17 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
December 31, 2017 | (17 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Effective Income Tax Rate Reconciliation | The effective income tax rate from continuing operations varies from the U.S. federal statutory rate principally due to the following:
| For the Year Ended December 31, 2018
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
U.S. Federal statutory rate | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | %
Increase (decrease) due to: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
State income taxes, net of Federal income tax benefit | 0.6 |  |  | (16.6 | ) |  | 8.3 |  |  | (2.6 | ) |  | 6.6 |  |  | 3.0 |  |  | 2.2 |  |  | 6.7 |  |  | 7.4 |
Qualified NDT fund income | (1.9 | ) |  | (11.8 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Amortization of investment tax credit, including deferred taxes on basis difference | (1.2 | ) |  | (6.5 | ) |  | (0.2 | ) |  | (0.1 | ) |  | (0.1 | ) |  | (0.2 | ) |  | (0.1 | ) |  | (0.3 | ) |  | (0.4 | )
Plant basis differences | (3.5 | ) |  | — |  |  | (0.2 | ) |  | (14.1 | ) |  | (1.3 | ) |  | (1.6 | ) |  | (2.7 | ) |  | (0.3 | ) |  | (0.5 | )
Production tax credits and other credits | (2.2 | ) |  | (13.5 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Noncontrolling interests | (1.0 | ) |  | (6.1 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Excess deferred tax amortization | (8.3 | ) |  | — |  |  | (9.1 | ) |  | (3.2 | ) |  | (8.0 | ) |  | (14.5 | ) |  | (14.8 | ) |  | (12.0 | ) |  | (14.9 | )
Tax Cuts and Jobs Act of 2017 | 0.9 |  |  | 2.7 |  |  | (0.1 | ) |  | — |  |  | — |  |  | 0.1 |  |  | — |  |  | — |  |  | — |
Other | 1.0 |  |  | 1.3 |  |  | 0.5 |  |  | 0.3 |  |  | 0.9 |  |  | 0.3 |  |  | 0.2 |  |  | 0.4 |  |  | 1.2 |
Effective income tax rate | 5.4 | % |  | (29.5 | )% |  | 20.2 | % |  | 1.3 | % |  | 19.1 | % |  | 8.1 | % |  | 5.8 | % |  | 15.5 | % |  | 13.8 | %
| For the Year Ended December 31, 2017(a)
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
U.S. Federal statutory rate | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | %
Increase (decrease) due to: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
State income taxes, net of Federal income tax benefit | 2.3 |  |  | 2.9 |  |  | 5.7 |  |  | 0.6 |  |  | 5.4 |  |  | 4.8 |  |  | 3.2 |  |  | 5.4 |  |  | 5.6 |
Qualified NDT fund income | 3.8 |  |  | 9.9 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Amortization of investment tax credit, including deferred taxes on basis difference | (0.9 | ) |  | (2.1 | ) |  | (0.2 | ) |  | (0.1 | ) |  | (0.1 | ) |  | (0.2 | ) |  | (0.1 | ) |  | (0.2 | ) |  | (0.4 | )
Plant basis differences(b) | (1.7 | ) |  | — |  |  | 0.3 |  |  | (13.8 | ) |  | 0.1 |  |  | 1.1 |  |  | (0.4 | ) |  | 2.0 |  |  | 3.6 |
Production tax credits and other credits | (1.8 | ) |  | (4.7 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Like-kind exchange | (1.2 | ) |  | — |  |  | 1.3 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Merger expenses | (3.6 | ) |  | (1.2 | ) |  | — |  |  | — |  |  | — |  |  | (9.5 | ) |  | (6.3 | ) |  | (7.8 | ) |  | (19.8 | )
FitzPatrick bargain purchase gain | (2.2 | ) |  | (5.6 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Tax Cuts and Jobs Act of 2017(c) | (33.1 | ) |  | (128.3 | ) |  | 0.1 |  |  | (2.3 | ) |  | 0.9 |  |  | 6.4 |  |  | 2.7 |  |  | 2.5 |  |  | 1.6 |
Other | 0.1 |  |  | (0.5 | ) |  | 0.2 |  |  | (0.1 | ) |  | 0.2 |  |  | (0.1 | ) |  | (0.2 | ) |  | 0.1 |  |  | (0.4 | )
Effective income tax rate | (3.3 | )% |  | (94.6 | )% |  | 42.4 | % |  | 19.3 | % |  | 41.5 | % |  | 37.5 | % |  | 33.9 | % |  | 37.0 | % |  | 25.2 | %
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Successor |  |  | Predecessor
| For the Year Ended December 31, 2016(a) |  | March 24, 2016 to December 31, 2016 |  |  | January 1, 2016 to March 23, 2016
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | Pepco |  | DPL (d) |  | ACE (d) |  | PHI (d) |  |  | PHI
U.S. Federal statutory rate | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  | 35.0 | % |  |  | 35.0 | %
Increase (decrease) due to: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
State income taxes, net of Federal income tax benefit (e) | 3.3 |  |  | 3.2 |  |  | 5.6 |  |  | 1.3 |  |  | 5.0 |  |  | 15.7 |  |  | 52.7 |  |  | 6.2 |  |  | 5.8 |  |  |  | 11.9 |
Qualified NDT fund income | 3.4 |  |  | 7.9 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  |  | — |
Amortization of investment tax credit, including deferred taxes on basis difference | (1.2 | ) |  | (2.3 | ) |  | (0.3 | ) |  | (0.1 | ) |  | (0.1 | ) |  | (0.2 | ) |  | (3.7 | ) |  | 0.8 |  |  | 1.4 |  |  |  | (0.9 | )
Plant basis differences | (4.9 | ) |  | — |  |  | (0.6 | ) |  | (9.6 | ) |  | (2.7 | ) |  | (22.8 | ) |  | (25.5 | ) |  | 10.3 |  |  | 39.0 |  |  |  | (13.5 | )
Production tax credits and other credits | (3.6 | ) |  | (8.3 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  |  | — |
Noncontrolling interests | (0.2 | ) |  | (0.6 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  |  | — |
Statute of limitations expiration | (0.4 | ) |  | (1.7 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  |  | — |
Penalties | 1.9 |  |  | — |  |  | 4.5 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (0.7 | ) |  |  | — |
Merger Expenses | 5.6 |  |  | 1.1 |  |  | — |  |  | — |  |  | — |  |  | 23.5 |  |  | 112.9 |  |  | (44.9 | ) |  | (89.0 | ) |  |  | 11.1 |
Other (f) | (0.7 | ) |  | (1.4 | ) |  | 0.1 |  |  | (1.2 | ) |  | — |  |  | (1.8 | ) |  | (2.2 | ) |  | 1.3 |  |  | 3.3 |  |  |  | 3.6 |
Effective income tax rate | 38.2 | % |  | 32.9 | % |  | 44.3 | % |  | 25.4 | % |  | 37.2 | % |  | 49.4 | % |  | 169.2 | % |  | 8.7 | % |  | (5.2 | )% |  |  | 47.2 | %
__________
(a) | Exelon retrospectively adopted the new standard Revenue from Contracts with Customers. The standard was adopted as of January 1, 2018. The effective income tax rates are recast to reflect the impact of the new standard.
(b) | Includes the charges related to the transmission-related income tax regulatory asset for Exelon, ComEd, BGE, PHI, Pepco, DPL and ACE of $35 million, $3 million, $5 million, $27 million, $14 million, $6 million and $7 million, respectively. See Note 4 - Regulatory Matters for additional information.
(c) | Included are impacts for TCJA other than the corporate rate change, including revisions further limiting tax deductions for compensation of certain highest paid executives, the write-off of foreign tax credit carryforwards, and loss of a 2015 domestic production activities deduction due to an NOL carryback.
(d) | DPL and ACE recognized a loss before income taxes for the year ended December 31, 2016, and PHI recognized a loss before income taxes for the period of March 24, 2016, through December 31, 2016. As a result, positive percentages represent an income tax benefit for the periods presented.
(e) | Includes a remeasurement of uncertain state income tax positions for Pepco and DPL.
(f) | At PECO, includes a cumulative adjustment related to an anticipated gas repairs tax return accounting method change. The method change request was filed and accepted in 2017. No change to the results recorded as of December 31, 2016.
Tax Effects of Temporary Differences | Tax Differences and Carryforwards The tax effects of temporary differences and carryforwards, which give rise to significant portions of the deferred tax assets (liabilities), as of December 31, 2018 and 2017 are presented below:
| As of December 31, 2018
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Plant basis differences | $ | (12,533 | ) |  | $ | (2,495 | ) |  | $ | (4,059 | ) |  | $ | (1,862 | ) |  | $ | (1,399 | ) |  | $ | (2,577 | ) |  | $ | (1,148 | ) |  | $ | (743 | ) |  | $ | (645 | )
Accrual based contracts | 117 |  |  | (44 | ) |  | — |  |  | — |  |  | — |  |  | 161 |  |  | — |  |  | — |  |  | — |
Derivatives and other financial instruments | 89 |  |  | 35 |  |  | 69 |  |  | — |  |  | — |  |  | 3 |  |  | — |  |  | — |  |  | — |
Deferred pension and postretirement obligation | 1,435 |  |  | (188 | ) |  | (255 | ) |  | (26 | ) |  | (26 | ) |  | (102 | ) |  | (78 | ) |  | (46 | ) |  | (14 | )
Nuclear decommissioning activities | (351 | ) |  | (351 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Deferred debt refinancing costs | 234 |  |  | 23 |  |  | (7 | ) |  | — |  |  | (3 | ) |  | 187 |  |  | (4 | ) |  | (2 | ) |  | (1 | )
Regulatory assets and liabilities | (749 | ) |  | — |  |  | 300 |  |  | (129 | ) |  | 172 |  |  | (90 | ) |  | 58 |  |  | 96 |  |  | 83 |
Tax loss carryforward | 237 |  |  | 78 |  |  | — |  |  | 18 |  |  | 25 |  |  | 96 |  |  | 12 |  |  | 52 |  |  | 26 |
Tax credit carryforward | 811 |  |  | 816 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Investment in partnerships | (797 | ) |  | (775 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Other, net | 934 |  |  | 239 |  |  | 151 |  |  | 67 |  |  | 12 |  |  | 196 |  |  | 98 |  |  | 17 |  |  | 19 |
Deferred income tax liabilities (net) | $ | (10,573 | ) |  | $ | (2,662 | ) |  | $ | (3,801 | ) |  | $ | (1,932 | ) |  | $ | (1,219 | ) |  | $ | (2,126 | ) |  | $ | (1,062 | ) |  | $ | (626 | ) |  | $ | (532 | )
Unamortized investment tax credits | (724 | ) |  | (700 | ) |  | (12 | ) |  | (1 | ) |  | (3 | ) |  | (8 | ) |  | (2 | ) |  | (2 | ) |  | (3 | )
Total deferred income tax liabilities (net) and unamortized investment tax credits | $ | (11,297 | ) |  | $ | (3,362 | ) |  | $ | (3,813 | ) |  | $ | (1,933 | ) |  | $ | (1,222 | ) |  | $ | (2,134 | ) |  | $ | (1,064 | ) |  | $ | (628 | ) |  | $ | (535 | )
| As of December 31, 2017 (a)
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Plant basis differences | $ | (12,490 | ) |  | $ | (2,819 | ) |  | $ | (3,825 | ) |  | $ | (1,762 | ) |  | $ | (1,368 | ) |  | $ | (2,521 | ) |  | $ | (1,152 | ) |  | $ | (717 | ) |  | $ | (607 | )
Accrual based contracts | 150 |  |  | (66 | ) |  | — |  |  | — |  |  | — |  |  | 216 |  |  | — |  |  | — |  |  | — |
Derivatives and other financial instruments | (85 | ) |  | (66 | ) |  | (2 | ) |  | — |  |  | — |  |  | 3 |  |  | — |  |  | — |  |  | — |
Deferred pension and postretirement obligation | 1,463 |  |  | (205 | ) |  | (285 | ) |  | (15 | ) |  | (29 | ) |  | (130 | ) |  | (78 | ) |  | (51 | ) |  | (18 | )
Nuclear decommissioning activities | (553 | ) |  | (553 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Deferred debt refinancing costs | 217 |  |  | 26 |  |  | (8 | ) |  | (1 | ) |  | (3 | ) |  | 203 |  |  | (4 | ) |  | (2 | ) |  | (1 | )
Regulatory assets and liabilities | (688 | ) |  | — |  |  | 489 |  |  | (90 | ) |  | 136 |  |  | (184 | ) |  | 39 |  |  | 88 |  |  | 86 |
Tax loss carryforward | 344 |  |  | 76 |  |  | 33 |  |  | 9 |  |  | 11 |  |  | 156 |  |  | 40 |  |  | 68 |  |  | 35 |
Tax credit carryforward | 861 |  |  | 868 |  |  | 1 |  |  | — |  |  | — |  |  | 6 |  |  | — |  |  | — |  |  | — |
Investment in partnerships | (434 | ) |  | (416 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Other, net | 746 |  |  | 78 |  |  | 141 |  |  | 71 |  |  | 13 |  |  | 193 |  |  | 94 |  |  | 14 |  |  | 16 |
Deferred income tax liabilities (net) | $ | (10,469 | ) |  | $ | (3,077 | ) |  | $ | (3,456 | ) |  | $ | (1,788 | ) |  | $ | (1,240 | ) |  | $ | (2,058 | ) |  | $ | (1,061 | ) |  | $ | (600 | ) |  | $ | (489 | )
Unamortized investment tax credits | (732 | ) |  | (705 | ) |  | (13 | ) |  | (1 | ) |  | (4 | ) |  | (8 | ) |  | (2 | ) |  | (3 | ) |  | (4 | )
Total deferred income tax liabilities (net) and unamortized investment tax credits | $ | (11,201 | ) |  | $ | (3,782 | ) |  | $ | (3,469 | ) |  | $ | (1,789 | ) |  | $ | (1,244 | ) |  | $ | (2,066 | ) |  | $ | (1,063 | ) |  | $ | (603 | ) |  | $ | (493 | )
Summary of Loss Carryforwards |
| As of December 31, 2018
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Plant basis differences | $ | (12,533 | ) |  | $ | (2,495 | ) |  | $ | (4,059 | ) |  | $ | (1,862 | ) |  | $ | (1,399 | ) |  | $ | (2,577 | ) |  | $ | (1,148 | ) |  | $ | (743 | ) |  | $ | (645 | )
Accrual based contracts | 117 |  |  | (44 | ) |  | — |  |  | — |  |  | — |  |  | 161 |  |  | — |  |  | — |  |  | — |
Derivatives and other financial instruments | 89 |  |  | 35 |  |  | 69 |  |  | — |  |  | — |  |  | 3 |  |  | — |  |  | — |  |  | — |
Deferred pension and postretirement obligation | 1,435 |  |  | (188 | ) |  | (255 | ) |  | (26 | ) |  | (26 | ) |  | (102 | ) |  | (78 | ) |  | (46 | ) |  | (14 | )
Nuclear decommissioning activities | (351 | ) |  | (351 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Deferred debt refinancing costs | 234 |  |  | 23 |  |  | (7 | ) |  | — |  |  | (3 | ) |  | 187 |  |  | (4 | ) |  | (2 | ) |  | (1 | )
Regulatory assets and liabilities | (749 | ) |  | — |  |  | 300 |  |  | (129 | ) |  | 172 |  |  | (90 | ) |  | 58 |  |  | 96 |  |  | 83 |
Tax loss carryforward | 237 |  |  | 78 |  |  | — |  |  | 18 |  |  | 25 |  |  | 96 |  |  | 12 |  |  | 52 |  |  | 26 |
Tax credit carryforward | 811 |  |  | 816 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Investment in partnerships | (797 | ) |  | (775 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Other, net | 934 |  |  | 239 |  |  | 151 |  |  | 67 |  |  | 12 |  |  | 196 |  |  | 98 |  |  | 17 |  |  | 19 |
Deferred income tax liabilities (net) | $ | (10,573 | ) |  | $ | (2,662 | ) |  | $ | (3,801 | ) |  | $ | (1,932 | ) |  | $ | (1,219 | ) |  | $ | (2,126 | ) |  | $ | (1,062 | ) |  | $ | (626 | ) |  | $ | (532 | )
Unamortized investment tax credits | (724 | ) |  | (700 | ) |  | (12 | ) |  | (1 | ) |  | (3 | ) |  | (8 | ) |  | (2 | ) |  | (2 | ) |  | (3 | )
Total deferred income tax liabilities (net) and unamortized investment tax credits | $ | (11,297 | ) |  | $ | (3,362 | ) |  | $ | (3,813 | ) |  | $ | (1,933 | ) |  | $ | (1,222 | ) |  | $ | (2,134 | ) |  | $ | (1,064 | ) |  | $ | (628 | ) |  | $ | (535 | )
| As of December 31, 2017 (a)
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Plant basis differences | $ | (12,490 | ) |  | $ | (2,819 | ) |  | $ | (3,825 | ) |  | $ | (1,762 | ) |  | $ | (1,368 | ) |  | $ | (2,521 | ) |  | $ | (1,152 | ) |  | $ | (717 | ) |  | $ | (607 | )
Accrual based contracts | 150 |  |  | (66 | ) |  | — |  |  | — |  |  | — |  |  | 216 |  |  | — |  |  | — |  |  | — |
Derivatives and other financial instruments | (85 | ) |  | (66 | ) |  | (2 | ) |  | — |  |  | — |  |  | 3 |  |  | — |  |  | — |  |  | — |
Deferred pension and postretirement obligation | 1,463 |  |  | (205 | ) |  | (285 | ) |  | (15 | ) |  | (29 | ) |  | (130 | ) |  | (78 | ) |  | (51 | ) |  | (18 | )
Nuclear decommissioning activities | (553 | ) |  | (553 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Deferred debt refinancing costs | 217 |  |  | 26 |  |  | (8 | ) |  | (1 | ) |  | (3 | ) |  | 203 |  |  | (4 | ) |  | (2 | ) |  | (1 | )
Regulatory assets and liabilities | (688 | ) |  | — |  |  | 489 |  |  | (90 | ) |  | 136 |  |  | (184 | ) |  | 39 |  |  | 88 |  |  | 86 |
Tax loss carryforward | 344 |  |  | 76 |  |  | 33 |  |  | 9 |  |  | 11 |  |  | 156 |  |  | 40 |  |  | 68 |  |  | 35 |
Tax credit carryforward | 861 |  |  | 868 |  |  | 1 |  |  | — |  |  | — |  |  | 6 |  |  | — |  |  | — |  |  | — |
Investment in partnerships | (434 | ) |  | (416 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Other, net | 746 |  |  | 78 |  |  | 141 |  |  | 71 |  |  | 13 |  |  | 193 |  |  | 94 |  |  | 14 |  |  | 16 |
Deferred income tax liabilities (net) | $ | (10,469 | ) |  | $ | (3,077 | ) |  | $ | (3,456 | ) |  | $ | (1,788 | ) |  | $ | (1,240 | ) |  | $ | (2,058 | ) |  | $ | (1,061 | ) |  | $ | (600 | ) |  | $ | (489 | )
Unamortized investment tax credits | (732 | ) |  | (705 | ) |  | (13 | ) |  | (1 | ) |  | (4 | ) |  | (8 | ) |  | (2 | ) |  | (3 | ) |  | (4 | )
Total deferred income tax liabilities (net) and unamortized investment tax credits | $ | (11,201 | ) |  | $ | (3,782 | ) |  | $ | (3,469 | ) |  | $ | (1,789 | ) |  | $ | (1,244 | ) |  | $ | (2,066 | ) |  | $ | (1,063 | ) |  | $ | (603 | ) |  | $ | (493 | )
__________
(a) | Includes remeasurement impacts related to the TCJA.
The following table provides the Registrants’ carryforwards and any corresponding valuation allowances as of December 31, 2018:
|  |  |  |  |  |  |  |  |  |  | Successor |  |  |  |  |  |  |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE |
Federal |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal general business credits carryforwards | 811 |  | (a) | 816 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |
State |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
State net operating losses | 4,103 |  | (b) | 1,544 |  | (b) | — |  |  | 224 |  | (c) | 395 |  | (d) | 1,492 |  | (e) | 192 |  | (f) | 772 |  | (g) | 365 |  | (h)
Deferred taxes on state tax attributes (net) | 272 |  |  | 104 |  |  | — |  |  | 18 |  |  | 26 |  |  | 102 |  |  | 12 |  |  | 52 |  |  | 26 |  |
Valuation allowance on state tax attributes | 35 |  |  | 26 |  |  | — |  |  | — |  |  | 1 |  |  | 6 |  |  | — |  |  | — |  |  | — |  |
__________
(a) | Exelon’s federal general business credit carryforwards will begin expiring in 2033.
(b) | Exelon’s and Generation's state net operating losses and credit carryforwards, which are presented on a post-apportioned basis, will begin expiring in 2019.
(c) | PECO's state net operating loss carryforwards, which are presented on a post-apportioned basis, will begin expiring in 2031.
(d) | BGE's state net operating loss carryforwards, which are presented on a post-apportioned basis, will begin expiring in 2026.
(e) | PHI's state net operating loss carryforwards, which are presented on a post-apportioned basis, will begin expiring in 2036.
(f) | Pepco's state net operating loss carryforwards, which are presented on a post-apportioned basis, will begin expiring in 2033.
(g) | DPL's state net operating loss carryforwards, which are presented on a post-apportioned basis, will begin expiring in 2030.
(h) | ACE's state net operating loss carryforwards, which are presented on a post-apportioned basis, will begin expiring in 2031.
Reconciliation of Unrecognized Tax Benefits Excluding Amounts Pertaining to Examined Tax Returns Foll Forward | The following tables provide a reconciliation of the Registrants’ unrecognized tax benefits as of December 31, 2018, 2017 and 2016:
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Unrecognized tax benefits at January 1, 2018 | $ | 743 |  |  | $ | 468 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 120 |  |  | $ | 125 |  |  | $ | 59 |  |  | $ | 21 |  |  | $ | 14 |
Change to positions that only affect timing | 15 |  |  | 15 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Increases based on tax positions prior to 2018 | 30 |  |  | 21 |  |  | — |  |  | — |  |  | — |  |  | 8 |  |  | 7 |  |  | 1 |  |  | — |
Decreases based on tax positions prior to 2018 | (251 | ) |  | (36 | ) |  | — |  |  | — |  |  | (120 | ) |  | (88 | ) |  | (66 | ) |  | (22 | ) |  | — |
Decrease from settlements with taxing authorities | (53 | ) |  | (53 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Decreases from expiration of statute of limitations | (7 | ) |  | (7 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Unrecognized tax benefits at December 31, 2018 | $ | 477 |  |  | $ | 408 |  |  | $ | 2 |  |  | $ | — |  |  | $ | — |  |  | $ | 45 |  |  | $ | — |  |  | $ | — |  |  | $ | 14 |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Unrecognized tax benefits at January 1, 2017 | $ | 916 |  |  | $ | 490 |  |  | $ | (12 | ) |  | $ | — |  |  | $ | 120 |  |  | $ | 172 |  |  | $ | 80 |  |  | $ | 37 |  |  | $ | 22 |
Increases based on tax positions prior to 2017 | 28 |  |  | — |  |  | 14 |  |  | — |  |  | — |  |  | 14 |  |  | — |  |  | — |  |  | 14 |
Decreases based on tax positions prior to 2017 | (196 | ) |  | (17 | ) |  | — |  |  | — |  |  | — |  |  | (61 | ) |  | (21 | ) |  | (16 | ) |  | (22 | )
Decrease from settlements with taxing authorities | (5 | ) |  | (5 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Unrecognized tax benefits at December 31, 2017 | $ | 743 |  |  | $ | 468 |  |  | $ | 2 |  |  | $ | — |  |  | $ | 120 |  |  | $ | 125 |  |  | $ | 59 |  |  | $ | 21 |  |  | $ | 14 |
| Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | PHI |  | Pepco |  | DPL |  | ACE
Unrecognized tax benefits at January 1, 2016 | $ | 1,078 |  |  | $ | 534 |  |  | $ | 142 |  |  | $ | — |  |  | $ | 120 |  |  | $ | 22 |  |  | $ | 8 |  |  | $ | 3 |  |  | $ | — |
Merger balance transfer | 22 |  |  | 5 |  |  | — |  |  | — |  |  | — |  |  | (5 | ) |  | — |  |  | — |  |  | — |
Increases based on tax positions related to 2016 | 108 |  |  | 10 |  |  | — |  |  | — |  |  | — |  |  | 59 |  |  | 21 |  |  | 16 |  |  | 22 |
Change to positions that only affect timing | (332 | ) |  | (12 | ) |  | (154 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Increases based on tax positions prior to 2016 | 88 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 96 |  |  | 51 |  |  | 18 |  |  | — |
Decreases based on tax positions prior to 2016 | (21 | ) |  | (20 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Decreases from settlements with taxing authorities | (27 | ) |  | (27 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Unrecognized tax benefits at December 31, 2016 | $ | 916 |  |  | $ | 490 |  |  | $ | (12 | ) |  | $ | — |  |  | $ | 120 |  |  | $ | 172 |  |  | $ | 80 |  |  | $ | 37 |  |  | $ | 22 |
Interest Income and Interest Expense Disclosure [Table Text Block] | The following tables set forth the net interest and penalty expense, including interest and penalties related to tax positions, recognized in Interest expense, net and Other, net in Other income and deductions in the Registrants’ Consolidated Statements of Operations and Comprehensive Income.
Net interest expense (income) for the years ended | Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | Pepco |  | DPL |  | ACE
December 31, 2018 | $ | (3 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
December 31, 2017 | 37 |  |  | (1 | ) |  | 11 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
December 31, 2016 | 165 |  |  | (13 | ) |  | 117 |  |  | — |  |  | — |  |  | 6 |  |  | — |  |  | (1 | )
Net penalty expense (income) for the years ended | Exelon |  | Generation |  | ComEd |  | PECO |  | BGE |  | Pepco |  | DPL |  | ACE
December 31, 2018 | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
December 31, 2017 | (2 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
December 31, 2016 | 106 |  |  | — |  |  | 86 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
| Successor |  |  | Predecessor
PHI | December 31, 2018 |  | December 31, 2017 |  | March 24, 2016 to December 31, 2016 |  |  | January 1, 2016 to March 23, 2016
Net interest expense | $ | — |  |  | $ | — |  |  | $ | (2 | ) |  |  | $ | — |
Summary of Open Tax Years by Jurisdiction | Description of tax years open to assessment by major jurisdiction
Taxpayer | Open Years
Exelon (and predecessors) and subsidiaries consolidated federal income tax returns | 1999, 2001-2017
PHI Holdings and subsidiaries consolidated federal income tax returns | 2013, 2015-2016
Exelon and subsidiaries Illinois unitary income tax returns | 2010-2017
Constellation combined New York corporate income tax returns | 2010-March 2012
Exelon combined New York corporate income tax returns | 2011-2017
Exelon New Jersey corporate income tax returns | 2013-2017
Exelon Pennsylvania corporate net income tax returns | 2011-2017
PECO Pennsylvania separate company returns | 2015-2017
DPL Delaware separate company returns | Same as federal
ACE New Jersey separate company returns | 2014-2017
Exelon and subsidiaries District of Columbia corporate income tax returns | 2015-2017
PHI Holdings and subsidiaries District of Columbia corporate income tax returns | 2015-2016
Various separate company Maryland corporate net income tax returns | Same as federal

X
- Definition ScheduleOfCategorizationOfNetRegulatoryLiabilitiesDueToTaxReform [Table Text Block] + References No definition available. + Details
Name: | exc_ScheduleOfCategorizationOfNetRegulatoryLiabilitiesDueToTaxReformTableTextBlock
Namespace Prefix: | exc_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule Of Remeasurements Of Deferred Income Taxes Due To Tax Reform [Table Text Block] + References No definition available. + Details
Name: | exc_ScheduleOfRemeasurementsOfDeferredIncomeTaxesDueToTaxReformTableTextBlock
Namespace Prefix: | exc_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Summary of Open Tax Years by Jurisdiction [Table Text Block] + References No definition available. + Details
Name: | exc_SummaryofOpenTaxYearsbyJurisdictionTableTextBlock
Namespace Prefix: | exc_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of interest income and expense, including, but not limited to, interest income and expense from investments, loans, and securities. + References No definition available. + Details
Name: | us-gaap_InterestIncomeAndInterestExpenseDisclosureTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
Name: | us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the change in unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 55 -Paragraph 217 -URI http://asc.fasb.org/extlink&oid=96868398&loc=d3e36027-109320 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
Name: | us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of deferred tax liabilities not recognized because of the exceptions to comprehensive recognition of deferred taxes, including a description of the temporary differences, events that would cause the temporary differences to become taxable, the cumulative amounts of the temporary differences and the amounts not recognized as deferred tax liabilities or a statement that the determination of the deferred tax liabilities is not practicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 740 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6487024&loc=d3e29054-158556 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=96869850&loc=d3e28200-109314 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331 + Details
Name: | us-gaap_SummaryOfDeferredTaxLiabilityNotRecognizedTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of pertinent information, such as tax authority, amounts, and expiration dates, of net operating loss carryforwards, including an assessment of the likelihood of utilization. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
Name: | us-gaap_SummaryOfOperatingLossCarryforwardsTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration