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Derivative and Other Fair Value Instruments - Additional Information (Details) | 1 Months Ended | 12 Months Ended
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Nov. 30, 2018 USD ($) DerivativeInstrument | Feb. 28, 2018 USD ($) DerivativeInstrument | Aug. 31, 2017 USD ($) DerivativeInstrument | Oct. 31, 2016 USD ($) DerivativeInstrument | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Derivative [Line Items] |  |  |  |  |  |  |
Unrealized gain (loss) on interest rate cash flow hedges, pretax, accumulated other comprehensive income (loss) |  |  |  |  | $ 65,000,000 | $ 88,600,000 |
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net |  |  |  |  | $ 20,900,000 |  |
Derivative instruments, gain (loss) recognized in income, ineffective portion and amount excluded from effectiveness testing, net |  |  |  |  |  |  | $ (74,000)
2.85% Notes [Member] |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Forward starting swaps settled | DerivativeInstrument |  |  |  | 1 |  |  |
Interest expense |  |  |  | $ 9,000 |  |  |
Increase (decrease) in charges hedge termination activities |  |  |  | $ 4,600,000 |  |  |
Debt instrument, term |  |  |  | 10 years |  |  |
Payments for (proceeds from) hedge, investing activities |  |  |  | $ 4,700,000 |  |  |
Proceeds from issuance of unsecured debt |  |  |  | 500,000,000 |  |  |
Derivative instruments, gain (loss) recognized in income, ineffective portion and amount excluded from effectiveness testing, net |  |  |  | $ (74,000) |  |  |
Forward Starting Swaps [Member] |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |
Proceeds from settlement of derivative instruments | $ 16,400,000 | $ 1,600,000 | $ 1,300,000 |  |  |  |
Forward starting swaps settled | DerivativeInstrument | 6 | 2 | 4 |  |  |  |
Interest expense | $ 120,000 |  |  |  |  |  |
Increase (decrease) in charges hedge termination activities | (16,500,000) | $ (1,600,000) | $ (1,300,000) |  |  |  |
Public notes, face value | $ 400,000,000 | $ 500,000,000 | $ 400,000,000 |  |  |  |
Debt instrument, term | 10 years | 10 years | 10 years |  |  |  |
Derivative instruments, gain (loss) recognized in income, ineffective portion and amount excluded from effectiveness testing, net |  |  |  |  |  |  | $ (74,000)

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- Definition Amount recorded in accumulated other comprehensive loss that will be recognized as an increase (decrease) to interest expense over the term of the note. + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986 + Details
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (210.5-03(11)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details
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- Definition The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994 + Details
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- Definition The cash outflow or inflow for a financial contract that meets the hedge criteria as either a cash flow hedge, fair value hedge, or hedge of a net investment in a foreign operation. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
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