Right to Use Liability - General Information (Details) $ in Thousands	3 Months Ended			12 Months Ended
	Sep. 30, 2016 lease item	Mar. 31, 2016 lease	Dec. 31, 2015 USD ($) item	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) item
Right to Use Liabilities
Number of operating leases	1	2				7
Number of leases, that had construction projects			25			25
Number of lease accounted for as finance leases			18			18
Number of leases accounted for as Capital leases			18			18
Percentage of land value of total real property value			25.00%			25.00%
Number of leases met the requirements to be reported as operating leases			30
Right to use assets derecognized | $			$ 122,400	$ 20,100	$ 19,958	$ 122,360
Derecognition resulted in the removal of right to use liabilities | $			127,000	20,000	$ 20,056	126,971
Derecognition resulted in deferred gain | $			$ 4,600	$ 100		$ 4,600
Number of month's rent the lease deposit is less than	2