Quarterly report pursuant to Section 13 or 15(d)

Information by Business Segment (Details 4)

v3.10.0.1
Information by Business Segment (Details 4) - USD ($)
$ in Thousands
Jun. 30, 2018
Dec. 31, 2017
Jun. 30, 2017
Reconciliation of segment assets to total assets      
Assets $ 3,612,362 $ 3,595,205 $ 3,592,304
Segment assets      
Reconciliation of segment assets to total assets      
Assets 3,042,452   2,993,078
Non-operating property assets      
Reconciliation of segment assets to total assets      
Assets 431,661   452,824
Other assets      
Reconciliation of segment assets to total assets      
Assets $ 138,249   $ 146,402