Revolving Credit Facilities and Mortgage Payable - Debt Covenants (Details)	1 Months Ended
	Sep. 30, 2018
Primary Credit Facility | JP Morgan
Debt Instrument [Line Items]
Leverage ratio maximum	3.75
Interest coverage ratio minimum	2.25
Adjusted leverage ratio to avoid limits on share repurchases	3.50
Japan Credit Facility
Debt Instrument [Line Items]
Interest coverage ratio minimum	1.00
Period of not having losses	2 years