Revolving Credit Facilities and Mortgage Payable - Mortgage (Details) - USD ($)	1 Months Ended
	Jul. 31, 2014	Sep. 30, 2018	Mar. 31, 2018
Debt Instrument [Line Items]
Short-term borrowings		$ 71,473,000	$ 578,000
Mortgage payable		31,210,000	$ 31,504,000
Mortgages
Debt Instrument [Line Items]
Debt instrument face amount	$ 33,900,000
Long-term debt gross		31,803,000
Short-term borrowings		592,000
Mortgage payable		$ 31,210,000
Fixed interest rate	4.928%
Debt amortization period	30 years
Balloon payment to be paid	$ 23,700,000