v3.8.0.1

Unsecured Credit Agreements - Summary of Unsecured Credit Agreements (Detail) - USD ($) $ in Thousands |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 23, 2017 | Dec. 31, 2017 | Apr. 18, 2017 | Dec. 31, 2016
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 1,181,470 |  | $ 869,524
Long-term Debt |  | $ 1,181,470 |  |
2015 Unsecured Term Loan Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maturity Date | Feb. 28, 2019 |  |  |
2015 Unsecured Term Loan Agreement | Minimum | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate | 0.90% |  |  |
2015 Unsecured Term Loan Agreement | Maximum | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate | 1.75% |  |  |
2017 Unsecured Revolving Credit and Term Loan Agreement | 5.5 Year Term Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maturity Date | Jan. 31, 2023 |  |  |
2017 Unsecured Revolving Credit and Term Loan Agreement | 7 Year Term Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maturity Date | Jun. 30, 2024 |  |  |
2017 Senior Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, interest rate |  |  | 4.84% |
Maturity Date |  | Apr. 18, 2017 |  |
Unsecured Debt |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 1,113,000 |  | 762,000
Debt issuance costs, net |  | (3,088) |  | (2,109)
Long-term Debt |  | 1,109,912 |  | 759,891
Unsecured Debt | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  |  |  | 223,000
Unsecured Debt | 3 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  |  |  | 50,000
Unsecured Debt | 2015 Unsecured Term Loan Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 325,000 |  | 375,000
Interest Rate |  | 1-month LIBOR + 1.40% |  |
Maturity Date |  | Feb. 28, 2019 |  |
Unsecured Debt | 2015 Unsecured Term Loan Agreement | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.40% |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 638,000 |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement | Revolver |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 273,000 |  |
Interest Rate |  | 1 and 3 month LIBOR + 1.20% |  |
Maturity Date |  | Jan. 31, 2022 |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement | Revolver | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.20% |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement | Revolver | 3 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.20% |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement | 5.5 Year Term Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 265,000 |  |
Interest Rate |  | 1-month LIBOR + 1.35% |  |
Maturity Date |  | Jan. 31, 2023 |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement | 5.5 Year Term Loan | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.35% |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement | 7 Year Term Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 100,000 |  |
Interest Rate |  | 1-month LIBOR + 1.90% |  |
Maturity Date |  | Jun. 30, 2024 |  |
Unsecured Debt | 2017 Unsecured Revolving Credit and Term Loan Agreement | 7 Year Term Loan | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.90% |  |
Unsecured Debt | 2017 Senior Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  | $ 150,000 |  |
Debt instrument, interest rate |  | 4.84% |  |
Maturity Date |  | Apr. 30, 2027 |  |
Unsecured Debt | 2012 Unsecured Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  |  |  | 202,000
Unsecured Debt | 2012 Unsecured Credit Agreement | Revolver |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  |  |  | 102,000
Interest Rate |  | 1-month LIBOR + 1.45% |  |
Maturity Date |  | Jun. 30, 2017 |  |
Unsecured Debt | 2012 Unsecured Credit Agreement | Revolver | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.45% |  |
Unsecured Debt | 2012 Unsecured Credit Agreement | Term Note One |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  |  |  | 50,000
Interest Rate |  | 3-month LIBOR + 1.45% |  |
Maturity Date |  | Jun. 30, 2017 |  |
Unsecured Debt | 2012 Unsecured Credit Agreement | Term Note One | 3 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.45% |  |
Unsecured Debt | 2012 Unsecured Credit Agreement | Term Note Two |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  |  |  | 50,000
Interest Rate |  | 1-month LIBOR + 1.45% |  |
Maturity Date |  | Jun. 30, 2017 |  |
Unsecured Debt | 2012 Unsecured Credit Agreement | Term Note Two | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.45% |  |
Unsecured Debt | 2013 Unsecured Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Carrying amount of debt |  |  |  | $ 185,000
Interest Rate |  | 1 month LIBOR + 1.75% |  |
Maturity Date |  | Oct. 31, 2018 |  |
Unsecured Debt | 2013 Unsecured Credit Agreement | Minimum | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 1.75% |  |
Unsecured Debt | 2013 Unsecured Credit Agreement | Maximum | 1 Month LIBOR |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Basis spread on variable rate |  | 2.50% |  |

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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 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 Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets. + 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 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/presentationRef -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 + 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 Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: 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(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: 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 Reference 3: 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 + Details
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