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Long-Term Debt - Additional Information (Details) | 1 Months Ended | 9 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2016 USD ($) day $ / shares | Sep. 30, 2017 USD ($) | Oct. 14, 2017 USD ($) | Sep. 25, 2017 USD ($) | Apr. 10, 2017 USD ($) | Mar. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |
Total long-term debt |  | $ 2,340,613,000 |  |  |  |  | $ 2,297,214,000
Ownership percentage, guarantors (as percent) |  | 100.00% |  |  |  |  |
Unsecured Senior Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term debt, fair value |  | $ 2,109,100,000 |  |  |  |  |
Swingline Loan [Member] | The Credit Agreement [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Credit facility borrowing base |  |  |  | $ 10,000,000 |  |  |
Line of Credit [Member] | Letter of Credit [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Line of credit facility, amount outstanding |  | 10,000,000 |  |  |  |  |
Line of Credit [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Line of credit facility amount |  | $ 2,500,000,000 |  |  |  |  |
Credit facility borrowing base |  |  |  |  | $ 1,600,000,000 | $ 1,150,000,000 |
Line of credit facility, current borrowing capacity |  |  |  |  | $ 1,150,000,000 |  |
Weighted average interest rate (as percent) |  | 3.00% |  |  |  |  |
Line of credit facility, remaining borrowing capacity |  | $ 745,000,000 |  |  |  |  |
Commitment fee percentage |  | 0.375% |  |  |  |  |
Line of Credit [Member] | Revolving Credit Facility [Member] | LIBOR [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Line of credit facility, amount outstanding |  | $ 395,000,000 |  |  |  |  |
Senior Unsecured Debt [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt issuance costs |  | 24,295,000 |  |  |  |  | 28,268,000
Long-term debt, gross |  | 2,052,950,000 |  |  |  |  | 2,052,950,000
Senior Unsecured Debt [Member] | Unsecured Senior Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Total long-term debt |  | 2,053,000,000 |  |  |  |  |
Senior Unsecured Debt [Member] | Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Unsecured debt |  | $ 1,753,000,000 |  |  |  |  |
Senior Unsecured Debt [Member] | Notes [Member] | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 6.50% |  |  |  |  |
Senior Unsecured Debt [Member] | Notes [Member] | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate (as percent) |  | 7.25% |  |  |  |  |
Senior Unsecured Debt [Member] | 7.25% senior unsecured notes due February 1, 2019 [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term debt, gross |  | $ 54,275,000 |  |  |  |  | 54,275,000
Stated interest rate (as percent) |  | 7.25% |  |  |  |  |
Number of days required for unsecured noted to be retired or refinanced prior to maturity |  | 90 days |  |  |  |  |
Senior Unsecured Debt [Member] | 6.5% senior unsecured notes due November 1, 2021 [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term debt, gross |  | $ 395,501,000 |  |  |  |  | 395,501,000
Stated interest rate (as percent) |  | 6.50% |  |  |  |  |
Senior Unsecured Debt [Member] | 6.875% senior unsecured notes due March 15, 2022 [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term debt, gross |  | $ 937,080,000 |  |  |  |  | 937,080,000
Stated interest rate (as percent) |  | 6.875% |  |  |  |  |
Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt discount | $ 93,200,000 | $ 83,042,000 |  |  |  |  | 90,468,000
Long-term debt, gross |  | $ 300,000,000 |  |  |  |  | $ 300,000,000
Stated interest rate (as percent) | 2.625% | 2.625% |  |  |  |  |
Debt issued | $ 300,000,000 |  |  |  |  |  |
Debt conversion rate per $1000 principal (in shares per $1000) | 0.0763650 |  |  |  |  |  |
Debt conversion price (in dollars per share) | $ / shares | $ 13.10 |  |  |  |  |  |
Debt instrument effective interest rate (percent) | 8.97% |  |  |  |  |  |
Estimated fair value of debt | $ 206,800,000 |  |  |  |  |  |
Debt Conversion Scenario 1 [Member] | Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Number of trading days | day | 20 |  |  |  |  |  |
Number of consecutive trading days | day | 30 |  |  |  |  |  |
Stock price relative to conversion price (percent) | 130.00% |  |  |  |  |  |
Debt Conversion Scenario 2 [Member] | Senior Unsecured Debt [Member] | 2.625% senior convertible notes due September 15, 2023 [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Number of trading days | day | 5 |  |  |  |  |  |
Number of consecutive trading days | day | 5 |  |  |  |  |  |
Stock price relative to product of sale price and conversion rate (percent) | 98.00% |  |  |  |  |  |
OMP Operating, LLC [Member] | Letter of Credit [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Credit facility borrowing base |  |  |  | 10,000,000 |  |  |
OMP Operating, LLC [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Credit facility borrowing base |  |  |  | 200,000,000 |  |  |
Line of Credit Facility, Maximum Borrowing Capacity, Accordian Feature |  |  |  | $ 400,000,000 |  |  |
Line of credit facility, amount outstanding |  | $ 0 |  |  |  |  |
OMP Operating, LLC [Member] | Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Commitment fee percentage |  | 0.375% |  |  |  |  |
OMP Operating, LLC [Member] | Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Commitment fee percentage |  | 0.50% |  |  |  |  |
OMP Operating, LLC [Member] | ABR Loans [Member] | Revolving Credit Facility [Member] | Federal Funds Effective Swap Rate [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 0.50% |  |  |  |  |
OMP Operating, LLC [Member] | ABR Loans [Member] | Revolving Credit Facility [Member] | LIBOR [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 1.00% |  |  |  |  |
OMP Operating, LLC [Member] | Eurodollar Loans [Member] | Revolving Credit Facility [Member] | LIBOR [Member] | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 1.75% |  |  |  |  |
OMP Operating, LLC [Member] | Eurodollar Loans [Member] | Revolving Credit Facility [Member] | LIBOR [Member] | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 2.75% |  |  |  |  |
OMP Operating, LLC [Member] | ABR Loans or Swingline Loans [Member] | Revolving Credit Facility [Member] | Federal Funds Effective Swap Rate [Member] | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 0.75% |  |  |  |  |
OMP Operating, LLC [Member] | ABR Loans or Swingline Loans [Member] | Revolving Credit Facility [Member] | Federal Funds Effective Swap Rate [Member] | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 1.75% |  |  |  |  |
OMP Operating, LLC [Member] | ABR Loans or Swingline Loans [Member] | Revolving Credit Facility [Member] | LIBOR [Member] | Minimum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 0.75% |  |  |  |  |
OMP Operating, LLC [Member] | ABR Loans or Swingline Loans [Member] | Revolving Credit Facility [Member] | LIBOR [Member] | Maximum [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Spread on variable rate |  | 1.75% |  |  |  |  |
Subsequent Event [Member] | Line of Credit [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Credit facility borrowing base |  |  | $ 1,600,000,000 |  |  |  |
Line of credit facility, current borrowing capacity |  |  | $ 1,150,000,000 |  |  |  |

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- Definition Debt Instrument, Convertible, Threshold Percentage of Stock Price to Product of Stock Sale Price and Conversion Rate + References No definition available. + Details
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- Definition Line of Credit Facility, Extension of Maturity Date Condition, Retirement Or Refinancing, Term + References No definition available. + Details
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- Definition Line of Credit Facility, Maximum Borrowing Capacity, Accordian Feature + References No definition available. + Details
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- Definition Ownership percentage, guarantor + References No definition available. + Details
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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, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + 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 FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 + Details
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- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21506-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21521-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644 Reference 4: 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(a)(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature. + References No definition available. + Details
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- Definition Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion. + References No definition available. + Details
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- Definition Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature. + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611 + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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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. + Details
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- Definition Amount, after accumulated amortization, of debt discount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 + Details
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- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
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- Definition Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + 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 FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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