XML 93 R79.htm IDEA: XBRL DOCUMENT
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Credit and Other Debt Agreements - Note Purchase Agreements - Additional Information (Detail) - USD ($) $ in Millions |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | ---
Nov. 30, 2018 | Jun. 24, 2018 | Jan. 13, 2018 | Aug. 04, 2017 | Aug. 02, 2017 | Jun. 27, 2017 | Jun. 13, 2017 | Dec. 31, 2018 | Dec. 31, 2017
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Realized a cash gain on hedging transaction |  |  |  |  |  |  |  |  | $ 8.3
Fixed Rate of 4.34% Balloon Due June 13, 2028 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.34% | 4.34%
Debt instrument, due date |  |  |  |  |  |  |  | 2028 | 2028
Fixed Rate of 4.44% Balloon Due June 13, 2030 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.44% | 4.44%
Debt instrument, due date |  |  |  |  |  |  |  | 2030 | 2030
Fixed Rate of 4.59% Balloon Due June 13, 2033 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.59% | 4.59%
Debt instrument, due date |  |  |  |  |  |  |  | 2033 | 2033
Fixed Rate of 4.69% Balloon Due June 13, 2038 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.69% | 4.69%
Debt instrument, due date |  |  |  |  |  |  |  | 2038 | 2038
Floating Interest Rate of 1.40% LIBOR Plus Balloon Due June 13, 2024 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Quarterly payments of interest |  |  |  |  |  |  |  | $ 50.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  | 1.40% | 1.40%
Debt instrument, interest rate description |  |  |  |  |  |  |  | 90 day LIBOR plus | 90 day LIBOR plus
Debt instrument, due date |  |  |  |  |  |  |  | 2024 | 2024
Note Purchase Agreements [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  | $ 500.0 |
Realized a cash gain on hedging transaction |  |  |  |  |  |  |  | $ 2.9 |
Amount payable to redeem the notes, percent of the principal amount |  |  |  |  |  |  |  | 100.00% |
Discount rate used to compute the remaining scheduled payments of principal and interest |  |  |  |  |  |  |  | U.S. Treasury yield plus 0.5% |
Note Purchase Agreements [Member] | Floating Interest Rate 4.39% LIBOR Due February 4, 2019 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Quarterly payments of interest |  |  |  |  |  |  |  |  | $ 50.0
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 4.39%
Debt instrument, maturity date |  |  |  |  |  |  |  |  | Feb. 04, 2019
Debt instrument, interest rate description |  |  |  |  |  |  |  |  | Three-month LIBOR
Note Purchase Agreements [Member] | Fixed Rate of 4.34% Balloon Due June 13, 2028 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  | $ 125.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.34% |
Debt instrument, due date |  |  |  |  |  |  |  | 2028 |
Debt instrument, interest raet effect to hedging gains |  |  |  |  |  |  |  | 4.00% |
Note Purchase Agreements [Member] | Fixed Rate of 4.44% Balloon Due June 13, 2030 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  | $ 125.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.44% |
Debt instrument, due date |  |  |  |  |  |  |  | 2030 |
Note Purchase Agreements [Member] | Fixed Rate of 4.59% Balloon Due June 13, 2033 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  | $ 125.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.59% |
Debt instrument, due date |  |  |  |  |  |  |  | 2033 |
Note Purchase Agreements [Member] | Fixed Rate of 4.69% Balloon Due June 13, 2038 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  | $ 75.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.69% |
Debt instrument, due date |  |  |  |  |  |  |  | 2038 |
Note Purchase Agreements [Member] | Floating Interest Rate of 1.40% LIBOR Plus Balloon Due June 13, 2024 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  | $ 50.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  | 1.40% |
Debt instrument, interest rate description |  |  |  |  |  |  |  | 90 day LIBOR plus |
Debt instrument, due date |  |  |  |  |  |  |  | 2024 |
Note Purchase Agreements [Member] | Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold | $ 50.0 | $ 50.0 |  |  |  |  |  |  |
Note Purchase Agreements [Member] | Senior Unsecured Notes [Member] | Private Placement [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  | $ 50.0 | $ 500.0 | $ 98.0 | $ 300.0 | $ 250.0 | $ 648.0 |  |
Note Purchase Agreements [Member] | Senior Fixed Rate Notes [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  | $ 450.0 |  |  |  |  |  | $ 598.0
Weighted average interest rate of notes |  |  | 4.42% |  |  |  |  |  | 4.04%
Quarterly payments of interest |  |  |  |  |  |  |  | $ 50.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  | 4.14% |
Debt instrument, maturity date |  |  |  |  |  |  |  | Feb. 04, 2019 |
Debt instrument, interest rate description |  |  |  |  |  |  |  | Three-month LIBOR |
Note Purchase Agreements [Member] | Senior Fixed Rate Notes [Member] | Weighted Average [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Weighted average maturity of notes |  |  |  |  |  |  |  | 13 years 7 months 6 days | 11 years 7 months 6 days
Note Purchase Agreements [Member] | 6.44% Senior Notes, Series B [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 300.0
Repayment of notes |  |  |  |  |  |  |  |  | $ 300.0
Debt instrument, maturity date |  |  |  |  |  |  |  |  | Aug. 03, 2017

X
- Definition Amount Payable to Redeem the Notes, Percent of the Principal Amount + References No definition available. + Details
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- Definition Discount Rate used to Compute the Remaining Scheduled Payments of Principal and Interest + 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 The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + References No definition available. + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: 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 3: 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=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 Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + 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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