Fair Value Measurements (Fair Value Measurements on a Nonrecurring Basis) (Details) - Real estate assets - Nonrecurring - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Financial Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Real estate asset	$ 0	$ 14,971,000
Level 1
Financial Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Real estate asset		0
Level 2
Financial Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Real estate asset		0
Level 3
Financial Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
Real estate asset		$ 14,971,000