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Borrowings - Additional Information (Detail) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2017 USD ($)
Debt Instrument [Line Items] |
Notes Payable | $ 4,492,834
Debt Instrument, Interest Rate, Effective Percentage | 3.50%
Debt Instrument, Maturity Date | Feb. 13, 2022
Conventional Variable Rate Debt [Member] |
Debt Instrument [Line Items] |
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate | 1.70%
Long-term Debt | $ 110,000
Capped Conventional Variable Rate Debt [Member] |
Debt Instrument [Line Items] |
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate | 1.70%
Long-term Debt | $ 50,000
Variable Rate Debt [Member] |
Debt Instrument [Line Items] |
Unsecured notes payable | $ 300,000
Debt Instrument, Interest Rate, Effective Percentage | 2.20%
Debt Instrument, Maturity Date | Aug. 29, 2020
Mortgages [Member] |
Debt Instrument [Line Items] |
Mortgage Loans on Real Estate | $ 9,000
Repayments of Debt | 156,400
Other Than Conventional Variable Rate Debt [Member] |
Debt Instrument [Line Items] |
Long-term Debt | $ 950,000
Debt Instrument Average Interest Rate | 4.00%
Fixed Rate Senior Notes [Member] |
Debt Instrument [Line Items] |
Unsecured notes payable | $ 2,800,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate | 3.80%
Secured Debt [Member] |
Debt Instrument [Line Items] |
Notes Payable | $ 1,109,973
Debt Instrument, Interest Rate, Effective Percentage | 3.60%
Debt Instrument, Maturity Date | Jul. 03, 2019
Secured Debt [Member] | Federal National Mortgage Association Certificates and Obligations (FNMA) [Member] |
Debt Instrument [Line Items] |
Line of Credit Facility, Amount Outstanding | $ 160,000
Line of Credit Facility, Maximum Borrowing Capacity | $ 160,000
Secured Debt [Member] | Federal National Mortgage Association Certificates and Obligations (FNMA) [Member] | Variable Rate Debt [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Interest Rate, Effective Percentage | 1.70%
Secured Debt [Member] | Mortgages [Member] | Fixed Rate Debt |
Debt Instrument [Line Items] |
Debt Instrument, Interest Rate, Effective Percentage | 4.00%
Debt Instrument, Maturity Date | Sep. 11, 2019
Mortgage Loans on Real Estate | $ 933,256
Unsecured Debt [Member] |
Debt Instrument [Line Items] |
Notes Payable | $ 3,382,861
Debt Instrument, Interest Rate, Effective Percentage | 3.50%
Debt Instrument, Maturity Date | Jan. 18, 2023
Unsecured Debt [Member] | Wells Fargo Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | $ 300,000
Unsecured Debt [Member] | US Bank Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | $ 150,000
Unsecured Debt [Member] | $1 billion unsecured revolving credit faciltiy [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Interest Rate, Effective Percentage | 2.14%
Letters of Credit Outstanding, Amount | $ 2,500
Unsecured Debt [Member] | $1 billion unsecured revolving credit faciltiy [Member] | Variable Rate Debt [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Interest Rate, Effective Percentage | 2.10%
Debt Instrument, Maturity Date | Apr. 15, 2020
Line of Credit Facility, Amount Outstanding | $ 250,000
Unsecured Debt [Member] | KeyBank Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | 150,000
Unsecured Debt [Member] | Public Income Notes [Member] | Fixed Rate Debt |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | 2,000,000
Unsecured Debt [Member] | Private Placement [Member] | Fixed Rate Debt |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | 310,000
Unsecured Debt [Member] | 3.6% Notes due 2027 [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | $ 600,000
Debt Instrument, Interest Rate, Effective Percentage | 3.68%
Debt Instrument, Unamortized Discount, Current | $ 2,500
Other Underwriting Expense | $ 3,900
Debt Instrument, Issue Price | 99.58%
Settlement of Forward Swaps | $ 300,000
Debt Instrument, Interest Rate, Stated Percentage | 3.60%
Proceeds from Unsecured Notes Payable | $ 593,600
Unsecured Debt [Member] | 2011 and 2012 Senior Notes [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | 310,000
Unsecured Debt [Member] | $1 billion unsecured revolving credit facility [Member] |
Debt Instrument [Line Items] |
Line of Credit Facility, Amount Outstanding | 250,000
Line of Credit Facility, Maximum Borrowing Capacity | 1,000,000
Unsecured Debt [Member] | Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Face Amount | $ 550,000
Debt Instrument, Interest Rate, Effective Percentage | 3.00%
Debt Instrument, Maturity Date | Apr. 17, 2018
Minimum [Member] | Unsecured Debt [Member] | Fixed Rate Debt |
Debt Instrument [Line Items] |
Debt Instrument, Term | 5 years
Minimum [Member] | Unsecured Debt [Member] | Wells Fargo Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 0.90%
Minimum [Member] | Unsecured Debt [Member] | $1 billion unsecured revolving credit faciltiy [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 0.85%
Minimum [Member] | Unsecured Debt [Member] | KeyBank Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 0.90%
Minimum [Member] | Unsecured Debt [Member] | Wells Fargo and US Bank Term Loans [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 0.90%
Minimum [Member] | Unsecured Debt [Member] | Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 0.90%
Maximum [Member] | Unsecured Debt [Member] | Fixed Rate Debt |
Debt Instrument [Line Items] |
Debt Instrument, Term | 12 years
Maximum [Member] | Unsecured Debt [Member] | Wells Fargo Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 1.90%
Maximum [Member] | Unsecured Debt [Member] | $1 billion unsecured revolving credit faciltiy [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 1.55%
Line of Credit Facility, Maximum Borrowing Capacity | $ 1,500,000
Maximum [Member] | Unsecured Debt [Member] | KeyBank Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 1.75%
Maximum [Member] | Unsecured Debt [Member] | Wells Fargo and US Bank Term Loans [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 1.90%
Maximum [Member] | Unsecured Debt [Member] | Term Loan [Member] |
Debt Instrument [Line Items] |
Debt Instrument, Basis Spread on Variable Rate | 1.75%
years to maturity [Member] | Unsecured Debt [Member] | Fixed Rate Debt |
Debt Instrument [Line Items] |
Debt Instrument, Term | 7 years 1 month 6 days

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