Investments - Additional Information (Details) $ in Thousands |
12 Months Ended |
|
Dec. 31, 2018
USD ($)
borrower
State
Property
note
loan
|
Dec. 31, 2017
USD ($)
borrower
Property
note
loan
|
Dec. 31, 2016
USD ($)
Property
|
| Investment [Line Items] |
|
|
|
| Financing Receivable, Number of Financing Receivables, Secured | note |
|
1
|
|
| Real estate properties and loans, gross |
$ 5,123,631
|
$ 7,903,025
|
$ 8,247,654
|
| Number of real estate properties invested in | Property |
1,514
|
2,480
|
2,615
|
| Number of states properties dispersed geographically | State |
49
|
|
|
| Number of states exceeding disclosure threshold | State |
1
|
|
|
| Minimum percentage of investment in real estate properties |
10.00%
|
|
|
| Number of notes receivable | note |
2
|
3
|
|
| Number of other notes receivable, non-secured | note |
|
2
|
|
| Amortization amount to rental revenue for capitalized leases |
$ 5,500
|
$ 6,500
|
$ 6,600
|
| Leases amortization expenses |
32,600
|
43,300
|
46,400
|
| Below market lease acquired |
$ 400
|
|
|
| Real estate assets held-for-sale expected selling period |
12 months
|
|
|
| Impairment of properties classified as held for sale |
$ 1,000
|
24,800
|
20,200
|
| Impairment of properties classified as held and used |
$ 16,700
|
$ 77,200
|
68,100
|
| In-place Leases |
|
|
|
| Investment [Line Items] |
|
|
|
| Lease intangibles weighted average amortization period |
14 years
|
13 years 9 months 18 days
|
|
| Acquired finite-lived intangible assets |
$ 21,700
|
|
|
| Above market leases |
|
|
|
| Investment [Line Items] |
|
|
|
| Lease intangibles weighted average amortization period |
10 years 1 month 6 days
|
9 years 6 months
|
|
| Acquired finite-lived intangible assets |
$ 3,500
|
|
|
| Below-market Leases |
|
|
|
| Investment [Line Items] |
|
|
|
| Lease intangibles weighted average amortization period |
17 years 8 months 12 days
|
17 years 6 months
|
|
| Leases |
|
|
|
| Investment [Line Items] |
|
|
|
| Lease intangibles weighted average amortization period |
10 years 7 months 6 days
|
10 years 7 months 6 days
|
|
| Single-Tenant Commercial Properties | First Mortgage |
|
|
|
| Investment [Line Items] |
|
|
|
| Number of first-priority mortgage loans | loan |
3
|
10
|
|
| Number of borrowers | borrower |
3
|
6
|
|
| Tenant Assets and Stock |
|
|
|
| Investment [Line Items] |
|
|
|
| Financing Receivable, Number of Financing Receivables, Secured | note |
1
|
|
|
| Other notes receivable |
$ 100
|
$ 3,500
|
|
| Texas |
|
|
|
| Investment [Line Items] |
|
|
|
| Percentage of investment in real estate properties |
12.00%
|
|
|
| Financed Properties |
|
|
|
| Investment [Line Items] |
|
|
|
| Real estate properties and loans, gross |
$ 47,044
|
$ 79,967
|
$ 66,578
|
| Number of real estate properties invested in | Property |
52
|
88
|
74
|