v3.19.3.a.u2

Unsecured Credit Agreements - Additional Information (Detail) |  |  |  |  |  |  |  |  |  | 6 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 28, 2019 USD ($) | Aug. 02, 2019 USD ($) | Jul. 01, 2019 | Feb. 27, 2019 USD ($) | Sep. 27, 2018 USD ($) | Sep. 13, 2018 USD ($) | Jul. 02, 2018 USD ($) | Jun. 23, 2017 USD ($) Bank Option | Apr. 18, 2017 USD ($) | Dec. 31, 2019 | Jun. 30, 2019 | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Feb. 28, 2019 USD ($) | Jan. 31, 2019 Option | Nov. 20, 2017 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 80,000,000
Revolving credit facility, available borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 880,000,000
Debt instrument, term |  |  |  |  |  |  |  |  |  |  |  | 119 months |  |  |  |  |
Weighted average interest rate on all outstanding borrowings |  |  |  |  |  |  |  |  |  | 3.68% |  | 3.68% | 4.23% |  |  |  |
Cost of debt extinguishment |  |  |  |  |  |  |  |  |  |  |  | $ (1,176,000) | $ (101,000) | $ (5,151,000) |  |  |
Deferred debt issuance costs, charged to interest expense |  |  |  |  |  |  |  |  |  |  |  | 2,542,000 | $ 1,776,000 | 1,893,000 |  |  |
Debt Issuance Costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of debt extinguishment |  |  |  |  |  |  |  |  |  |  |  | 6,000 |  |  |  |  |
Other Nonoperating Income (Expense) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of debt extinguishment |  |  |  |  |  |  |  |  |  |  |  | $ 328,000 |  |  |  |  |
Unamortized debt issuance costs |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 654,000 |  |  |
Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 425,000,000
2023 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 265,000,000
Commitment fee percentage |  |  |  |  |  |  |  | 0.25% |  |  |  |  |  |  |  |  |
2024 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 190,000,000
Commitment fee percentage |  |  |  |  |  |  |  | 0.25% |  |  |  |  |  |  |  |  |
Senior Guaranteed Notes Series B and Senior Guaranteed Notes Series C | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 325,000,000 |  |  |  |  |  |  |  |  |  |
Senior Guaranteed Notes Series B | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  | Jul. 02, 2028 |  |  |  |  | Jul. 31, 2028 |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 225,000,000 |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of debt |  |  |  |  |  | $ 125,000,000 | $ 100,000,000 |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  |  | 5.09% |  |  | 5.09% |  | 5.09% |  |  |  |  |
Senior Guaranteed Notes Series C | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  | Jul. 02, 2030 |  |  |  |  | Jul. 31, 2030 |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 100,000,000 |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of debt |  |  |  |  |  | $ 50,000,000 | $ 50,000,000 |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  |  | 5.19% |  |  | 5.19% |  | 5.19% |  |  |  |  |
Baa3 Rating | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 1.20% |  |  |  |  |  |  |  |  |
Commitment fee percentage |  |  |  |  |  |  |  | 0.25% |  |  |  |  |  |  |  |  |
Baa3 Rating | 2023 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 1.35% |  |  |  |  |  |  |  |  |
Baa3 Rating | 2024 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 1.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |
2019 Unsecured Term Loan Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
One time non pro rata paydown amount |  |  |  |  |  |  |  | $ 50,000,000 |  |  |  |  |  |  |  |  |
One Time Pro Rata Pay Down Amount |  |  |  |  | $ 25,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Repayment of borrowing |  |  |  | $ 300,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
2019 Unsecured Term Loan Agreement | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  | Feb. 29, 2020 |  |  |  |  |
Repayments on unsecured term loan |  |  |  |  |  |  | $ 25,000,000 |  |  |  |  |  |  |  |  |  |
2019 Unsecured Term Loan Agreement | 1 Month LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of option available to extend maturity period | Option |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |
2019 Unsecured Term Loan Agreement | 1 Month LIBOR | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  | 1.40% |  |  |  |  |
Two Thousand Nineteen Unsecured Term Loan Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  | Feb. 28, 2019 |  |  |  |  |  |  |  |  |
Two Thousand Nineteen Unsecured Term Loan Agreement | Baa3 Rating |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 1.40% |  |  |  |  |  |  |  |  |
Two Thousand Nineteen Unsecured Term Loan Agreement | 1 Month LIBOR | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 0.90% |  |  |  |  |  |  |  |  |
Two Thousand Nineteen Unsecured Term Loan Agreement | 1 Month LIBOR | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 1.75% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  | $ 800,000,000 |  |  |  |  |  |  |  |  |
Number of participating banks as joint lead arrangers and joint bookrunners | Bank |  |  |  |  |  |  |  | 4 |  |  |  |  |  |  |  |  |
Number of participating banks as co-syndication agents | Bank |  |  |  |  |  |  |  | 4 |  |  |  |  |  |  |  |  |
Number of participating banks as co-documentation agents | Bank |  |  |  |  |  |  |  | 4 |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,055,000,000 |  |
Line of credit, maximum accordion feature |  |  |  |  |  |  |  | $ 1,000,000,000 |  |  |  |  |  |  |  |  |
Revolving credit facility, available borrowing capacity |  |  |  | $ 425,000,000 |  |  |  |  |  |  |  |  |  |  | $ 600,000,000 |  |
Unsecured Revolving Credit and Term Loan Agreement | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  | Jan. 21, 2022 |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  |  |  |  |  |  |  | $ 400,000,000 |  |  |  |  |  |  |  |  |
Sublimit for swingline loans |  |  |  |  |  |  |  | 35,000,000 |  |  |  |  |  |  |  |  |
Amount available for issuance of letters of credit |  |  |  |  |  |  |  | $ 20,000,000 |  |  |  |  |  |  |  |  |
Number of option available to extend maturity period | Option |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |
Maturity extension period |  |  |  |  |  |  |  | 5 months |  |  |  |  |  |  |  |  |
Maturity extension fee percentage |  |  |  |  |  |  |  | 0.0625% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | Revolving Credit Facility | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  | Jan. 31, 2022 |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 5.5 Year Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  | $ 250,000,000 |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 7 Year Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  | $ 150,000,000 |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 2023 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  | Jan. 31, 2023 |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 2023 Unsecured Term Loan | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  | Jan. 31, 2023 |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 2024 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  |  | 1.90% |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 2024 Unsecured Term Loan | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  | Jun. 30, 2024 |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | Minimum | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage |  |  |  |  |  |  |  | 0.13% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | Minimum | 2024 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  | 0.85% | 1.50% |  | 1.90% |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | Maximum | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage |  |  |  |  |  |  |  | 0.30% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | Maximum | 2024 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  | 1.65% | 2.45% |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 1 Month LIBOR | Revolving Credit Facility | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  | 1.20% |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 1 Month LIBOR | 2023 Unsecured Term Loan | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  | 1.35% |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | 1 Month LIBOR | 2024 Unsecured Term Loan | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  | 1.25% |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | LIBOR | Minimum | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 0.825% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | LIBOR | Minimum | 2023 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 0.90% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | LIBOR | Minimum | 2024 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 0.85% |  |  |  |  |  |  |  |  |  | 1.50% |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | LIBOR | Maximum | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 1.55% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | LIBOR | Maximum | 2023 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  | 1.75% |  |  |  |  |  |  |  |  |
Unsecured Revolving Credit and Term Loan Agreement | LIBOR | Maximum | 2024 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 1.65% |  |  |  |  |  |  |  |  |  | 2.45% |  |  |  |
2026 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  | Feb. 27, 2026 |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  | $ 450,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit, maximum accordion feature |  |  |  | $ 550,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage |  |  |  | 0.25% |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term |  |  |  | 7 years |  |  |  |  |  |  |  |  |  |  |  |  |
Remaining borrowing capacity |  |  |  | $ 150,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
2026 Unsecured Term Loan | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  | Feb. 28, 2026 |  |  |  |  |
2026 Unsecured Term Loan | 1 Month LIBOR | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  | 1.85% |  |  |  |  |
2026 Unsecured Term Loan | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  | 1.85% |  |  |  |  |  |  |  |  |  |  |  |  |
2026 Unsecured Term Loan | LIBOR | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  | 1.45% |  |  |  |  |  |  |  |  |  |  |  |  |
2026 Unsecured Term Loan | LIBOR | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  |  | 2.40% |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  | Aug. 02, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  | $ 300,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage |  | 0.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of debt | $ 300,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Unsecured Term Loan | Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  | Aug. 31, 2020 |  |  |  |  |
Basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  | 1.25% |  |  |  |  |
2020 Unsecured Term Loan | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 1.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Unsecured Term Loan | LIBOR | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 0.85% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Unsecured Term Loan | LIBOR | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  | 1.65% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2017 Senior Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date |  |  |  |  |  |  |  |  |  |  |  |  |  | Apr. 18, 2017 |  |  |
Debt instrument, term |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |
Proceeds from issuance of debt |  |  |  |  |  |  |  |  | $ 150,000,000 |  |  |  |  |  |  |  |
Debt instrument, interest rate |  |  |  |  |  |  |  |  | 4.84% |  |  |  |  |  |  |  |
Issuance date |  |  |  |  |  |  |  |  |  |  |  |  |  | Apr. 18, 2027 |  |  |
2017 Senior Notes | 10-Year U.S. Treasury Yield |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument basis spread on reference rate |  |  |  |  |  |  |  |  | 2.40% |  |  |  |  |  |  |  |
Two Thousand Twenty Six Unsecured Term Loan And Amended Unsecured Revolving Credit And Term Loan Agreement And Two Thousand Twenty Unsecured Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issuance costs incurred |  |  |  |  |  |  |  |  |  |  |  | $ 6,549,000 |  |  |  |  |
Senior Guaranteed Notes Series B and Senior Guaranteed Notes Series C |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issuance costs incurred |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,209,000 |  |  |  |
Senior Guaranteed Notes Series A |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issuance costs incurred |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 8,711,000 |  |  |
New Debt Agreements [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized debt issuance costs |  |  |  |  |  |  |  |  |  |  |  | $ 6,543,000 |  |  |  |  |
Deferred debt issuance costs, charged to interest expense |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,810,000 |  |  |
Restated Term Loan Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of debt extinguishment |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,901,000 |  |  |

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