Commitments and Contingencies (Details)	Dec. 31, 2018 USD ($) lease
Commitments and Contingencies Disclosure [Abstract]
Number of non cancelable ground leases \| lease	8
Operating Leases, Future Minimum Payments Due [Abstract]
2019	$ 6,811,000
2020	6,855,000
2021	6,877,000
2022	6,888,000
2023	6,860,000
Thereafter	153,258,000
Total future operating lease minimum payments	187,549,000
Property casualty insurance, deductible per incident, maximum	5,000,000.0
Pacific Western Insurance LLC [Member]
Guarantor Obligations [Line Items]
Investments and Cash	$ 86,600,000

Number of non-cancelable ground leases.

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Sum of investments and unrestricted cash as of the balance sheet date.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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