Intangible Assets and Liabilities - Narratives (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Intangible Assets And Liabilities [Abstract] | |||
| Net amortization of intangibles | $ 37,000,000 | $ 36,700,000 | $ 38,000,000 |
| Goodwill impairment | $ 0 | ||