Corporate Office Relocation - Contract Termination and Relocation (Details) - Corporate Office Relocation - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring and Other Charges
Additions for costs expensed	$ 2,100	$ 0	$ 2,113
Remaining lease costs
Restructuring and Other Charges
Additions for costs expensed			1,258
Impairment of leasehold improvements and furniture and fixtures
Restructuring and Other Charges
Additions for costs expensed	$ 795		795
Relocation costs
Restructuring and Other Charges
Additions for costs expensed			$ 60