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v3.19.3.a.u2

Credit and Other Debt Agreements - Note Purchase Agreements - Additional Information (Detail) - USD ($) $ in Millions |  |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 30, 2020 | Dec. 02, 2019 | Jun. 12, 2019 | Feb. 13, 2019 | Nov. 30, 2018 | Jun. 24, 2018 | Jun. 13, 2018 | Jan. 13, 2018 | Dec. 31, 2019 | Dec. 31, 2018
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] |  |  |  |  |  |  |  |  |  |
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
Fixed Rate of 4.72%, Balloon due February 13, 2024 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 100.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 4.72% | 4.72%
Debt instrument, due date |  |  |  |  |  |  |  |  | 2024 | 2024
Fixed Rate of 4.85%, Balloon due February 13, 2026 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 140.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 4.85% | 4.85%
Debt instrument, due date |  |  |  |  |  |  |  |  | 2026 | 2026
Fixed Rate of 5.04%, Balloon due February 13, 2029 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 100.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 5.04% | 5.04%
Debt instrument, due date |  |  |  |  |  |  |  |  | 2029 | 2029
Fixed Rate of 5.14%, Balloon due March 13, 2031 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 180.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 5.14% | 5.14%
Debt instrument, due date |  |  |  |  |  |  |  |  | 2031 | 2031
Fixed Rate of 5.29%, balloon due March 13, 2034 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 40.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 5.29% | 5.29%
Debt instrument, due date |  |  |  |  |  |  |  |  | 2034 | 2034
Fixed Rate of 5.45%, balloon due March 13, 2039 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 40.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 5.45% | 5.45%
Debt instrument, due date |  |  |  |  |  |  |  |  | 2039 | 2039
Fixed Rate of 3.75% senior notes due in 2027 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 30.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 3.75% |
Debt instrument, due date |  |  |  |  |  |  |  |  | 2027 |
Fixed Rate of 3.99% senior notes due in 2030 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 341.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 3.99% |
Debt instrument, due date |  |  |  |  |  |  |  |  | 2030 |
Fixed Rate of 4.09% senior notes due in 2032 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 69.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 4.09% |
Debt instrument, due date |  |  |  |  |  |  |  |  | 2032 |
Fixed Rate of 4.24% senior notes due in 2035 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 79.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 4.24% |
Debt instrument, due date |  |  |  |  |  |  |  |  | 2035 |
Fixed Rate of 4.49% senior notes due in 2040 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 56.0 |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 4.49% |
Debt instrument, due date |  |  |  |  |  |  |  |  | 2040 |
Note Purchase Agreements [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  |  | $ 500.0 |
Realized a cash gain on hedging transaction |  |  | $ 5.2 | $ 1.2 |  |  |  |  | $ 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] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Realized a cash gain on hedging transaction | $ 8.9 |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  | 3.14%
Debt instrument, maturity date |  |  |  |  |  |  |  |  |  | Feb. 03, 2020
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 |
Quarterly payments of interest |  |  |  |  |  |  |  |  | $ 50.0 | $ 50.0
Debt instrument, interest rate description |  |  |  |  |  |  |  |  | 90 day LIBOR plus |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 1.40% |
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 |  |  |  | 600.0 |  | $ 50.0 | $ 500.0 |  |  |
Note Purchase Agreements [Member] | Senior Fixed Rate Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  |  |  |  |  | $ 450.0 |  |
Weighted average interest rate of notes |  |  |  |  |  |  |  | 4.42% |  |
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 |
Note Purchase Agreements [Member] | Fixed Rate Senior Unsecured Notes [Member] | Private Placement [Member] | Tranche One Member |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  | 340.0 |  |  |  |  |  |
Note Purchase Agreements [Member] | Fixed Rate Senior Unsecured Notes [Member] | Private Placement [Member] | Tranche Two Member |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  |  | $ 260.0 |  |  |  |  |  |
Note Purchase Agreements [Member] | Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Weighted average interest rate of notes |  |  |  | 5.04% |  |  |  |  |  |
Note Purchase Agreements [Member] | Unsecured Notes [Member] | Private Placement [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  | $ 50.0 | $ 175.0 |  |  |  |  |  |  |
Weighted average interest rate of notes |  | 3.48% |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  | 4.48% |  |  |  |  |  |  |
Debt instrument, due date |  |  | 2034 |  |  |  |  |  |  |
Note Purchase Agreements [Member] | Unsecured Notes [Member] | Private Placement [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold | $ 575.0 |  |  |  |  |  |  |  |  |
Weighted average maturity of notes | 11 years 8 months 12 days |  |  |  |  |  |  |  |  |
Weighted average interest rate of notes | 4.23% |  |  |  |  |  |  |  |  |
Note Purchase Agreements [Member] | Unsecured Notes [Member] | Private Placement [Member] | Weighted Average [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Weighted average maturity of notes |  |  |  | 10 years 1 month 6 days |  |  |  |  |  |
Note Purchase Agreements [Member] | Series K Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  |  | $ 50.0 |  |  |  |  |  |  |
Weighted average interest rate of notes |  |  | 4.68% |  |  |  |  |  |  |
Note Purchase Agreements [Member] | Series C Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Notes issued and sold |  | $ 50.0 |  |  |  |  |  |  |  |

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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 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=117815213&loc=d3e19207-110258 + Details
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