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Fair Value Measurements (Schedule Of Carrying Values And Estimated Fair Values Of Debt Instruments) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2013 | Dec. 31, 2011 | Dec. 31, 2017 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2018
Fair Value Measurement [Domain] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Liabilities Subject to Compromise |  |  |  |  |  | $ 940.8 |  |
Current maturities of long-term debt |  |  |  |  |  | 0.0 | $ 124.8 |
Long-term Debt, Excluding Current Maturities |  |  |  |  |  | 0.0 | 5,923.5 |
Liabilities Subject to Compromise |  |  |  |  |  | 7,313.7 | 0.0 |
Debt Instrument, Convertible, Carrying Amount of Equity Component |  |  |  |  |  | $ 220.0 |  |
6.875% Senior notes due 2020 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 6.875% |  |
6.875% Senior notes due 2020 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage | 6.875% |  |  |  |  |  |  |
Senior Note Maturity Year | 2020 |  |  |  |  |  |  |
4.70% Senior notes due 2021 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 4.70% |  |
4.70% Senior notes due 2021 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  | 4.70% |  |  |  |  |  |
Senior Note Maturity Year |  | 2021 |  |  |  |  |  |
4.875%SeniorNotesDue2022Member [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 4.875% |  |
4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 4.875% |  |
3.00% Exchangeable senior notes due 2024 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 3.00% |  |
3.00% Exchangeable senior notes due 2024 | Convertible Debt [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Carrying Amount of Equity Component |  |  |  |  |  | $ 220.0 | $ 220.0 |
4.50% Senior notes due 2024 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 4.50% |  |
4.50% Senior notes due 2024 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  | 4.50% |  |  |
Senior Note Maturity Year |  |  |  |  | 2024 |  |  |
4.75%SeniorNotesDue2024Member [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 4.75% |  |
4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 4.75% |  |
8.00% Senior notes due 2024 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 8.00% |  |
8.00% Senior notes due 2024 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  | 8.00% |  |  |  |  |
Senior Note Maturity Year |  |  | 2024 |  |  |  |  |
5.20% Senior notes due 2025 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 5.20% |  |
5.20% Senior notes due 2025 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  | 5.20% |  |  |  |
Senior Note Maturity Year |  |  |  | 2025 |  |  |  |
7.38%SeniorNotesDue2025 [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 7.375% |  |
7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 7.375% |  |
7.75% Senior notes due 2026 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 7.75% |  |
7.75% Senior notes due 2026 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  |  |  | 7.75%
7.20% Senior notes due 2027 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 7.20% |  |
7.20% Senior notes due 2027 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  |  | 7.20% |
7.875% Senior notes due 2040 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 7.875% |  |
5.40%SeniorNotesDue2042 [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 5.40% |  |
5.75% Senior notes due 2044 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 5.75% |  |
5.75% Senior notes due 2044 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  | 5.75% | 5.75% |  |  |
Senior Note Maturity Year |  |  |  | 2044 | 2044 |  |  |
5.85%SeniorNotesDue2044 [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 5.85% |  |
5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  |  | 5.85% |  |
Reported Value Measurement [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | $ 7,096.3 | $ 6,048.3 |
Long-term Debt, Excluding Current Maturities |  |  |  |  |  | 0.0 | 5,923.5 |
Liabilities Subject to Compromise |  |  |  |  |  | 7,096.3 |  |
Reported Value Measurement [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Liabilities Subject to Compromise |  |  |  |  |  | 6,500.0 |  |
Reported Value Measurement [Member] | 6.875% Senior notes due 2020 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 122.9 | 124.8 |
Reported Value Measurement [Member] | 4.70% Senior notes due 2021 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 100.7 | 113.2 |
Reported Value Measurement [Member] | 4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 620.8 | 599.2 |
Reported Value Measurement [Member] | 3.00% Exchangeable senior notes due 2024 | Convertible Debt [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 849.5 | 699.0 |
Reported Value Measurement [Member] | 4.50% Senior notes due 2024 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 303.4 | 302.0 |
Reported Value Measurement [Member] | 4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 318.6 | 276.5 |
Reported Value Measurement [Member] | 8.00% Senior notes due 2024 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 292.3 | 295.7 |
Reported Value Measurement [Member] | 5.20% Senior notes due 2025 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 333.7 | 331.7 |
Reported Value Measurement [Member] | 7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 360.8 | 329.2 |
Reported Value Measurement [Member] | 7.75% Senior notes due 2026 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 1,000.0 | 987.1 |
Reported Value Measurement [Member] | 7.20% Senior notes due 2027 | Debentures Due 2027 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 112.1 | 111.7 |
Reported Value Measurement [Member] | 7.875% Senior notes due 2040 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 300.0 | 373.3 |
Reported Value Measurement [Member] | 5.40%SeniorNotesDue2042 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 400.0 | 262.8 |
Reported Value Measurement [Member] | 5.75% Senior notes due 2044 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 1,000.5 | 973.3 |
Reported Value Measurement [Member] | 5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Long-term Debt |  |  |  |  |  | 400.0 | 268.8 |
Estimate of Fair Value Measurement [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 940.8 | 3,874.1 |
Current maturities of long-term debt |  |  |  |  |  | 0.0 | 0.0 |
Long-term Debt, Fair Value |  |  |  |  |  | 0.0 | 3,874.1 |
Estimate of Fair Value Measurement [Member] | Line of Credit [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 581.0 |  |
Estimate of Fair Value Measurement [Member] | 6.875% Senior notes due 2020 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 8.6 | 117.3 |
Estimate of Fair Value Measurement [Member] | 4.70% Senior notes due 2021 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 4.5 | 95.5 |
Estimate of Fair Value Measurement [Member] | 4.875%SeniorNotesDue2022Member [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 32.9 | 460.5 |
Estimate of Fair Value Measurement [Member] | 3.00% Exchangeable senior notes due 2024 | Convertible Debt [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 76.5 | 607.4 |
Estimate of Fair Value Measurement [Member] | 4.50% Senior notes due 2024 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 13.7 | 167.2 |
Estimate of Fair Value Measurement [Member] | 4.75%SeniorNotesDue2024Member [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 18.8 | 201.4 |
Estimate of Fair Value Measurement [Member] | 8.00% Senior notes due 2024 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 12.9 | 181.7 |
Estimate of Fair Value Measurement [Member] | 5.20% Senior notes due 2025 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 12.7 | 186.7 |
Estimate of Fair Value Measurement [Member] | 7.38%SeniorNotesDue2025 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 20.9 | 218.6 |
Estimate of Fair Value Measurement [Member] | 7.75% Senior notes due 2026 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 44.0 | 575.1 |
Estimate of Fair Value Measurement [Member] | 7.20% Senior notes due 2027 | Debentures Due 2027 |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 5.7 | 70.0 |
Estimate of Fair Value Measurement [Member] | 7.875% Senior notes due 2040 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 21.0 | 153.5 |
Estimate of Fair Value Measurement [Member] | 5.40%SeniorNotesDue2042 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 23.6 | 194.4 |
Estimate of Fair Value Measurement [Member] | 5.75% Senior notes due 2044 | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | 38.0 | 450.0 |
Estimate of Fair Value Measurement [Member] | 5.85%SeniorNotesDue2044 [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |  |
Debt instrument, Fair Value Disclosure |  |  |  |  |  | $ 26.0 | $ 194.8 |

X
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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Total amount of liabilities subject to compromise. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120604989&loc=d3e56015-112765 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 55 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=116635682&loc=d3e55717-112764 + Details
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