Represents the number of properties the Company is leasing.

No definition available.

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- Definition

Represents the number of mortgages assumed.

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No definition available.

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- Definition

Amount of liabilities assumed at the acquisition date.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- Definition

Amount of stock repurchase plan authorized.

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No definition available.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Related Party Transactions (Details) $ / shares in Units, $ in Millions	1 Months Ended		5 Months Ended	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2017 USD ($) loan shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2017 USD ($)	Oct. 31, 2019 USD ($)	Aug. 31, 2018 USD ($)	May 31, 2018 USD ($)	Feb. 28, 2017 USD ($) item
Related party transactions
Number of shares purchased and cancelled under the share repurchase program \| shares		216,350	825,146
Amount paid for shares purchased and cancelled under share repurchase program		$ 5.0	$ 20.0
Share repurchase authorized amount						$ 50.0	$ 20.0	$ 5.0	$ 5.0
Number of leased properties \| item									3
SIGI
Related party transactions
Purchase of properties		$ 12.8
Lease payments to related party					$ 0.2
SIGI \| Mortgages
Related party transactions
Number of mortgages assumed \| loan		3
Assumed notes		$ 4.2
Former Board of Director
Related party transactions
Number of shares purchased and cancelled under the share repurchase program \| shares	2,316,960			2,316,960
Amount paid for shares purchased and cancelled under share repurchase program	$ 50.0			$ 50.0
Share price (in dollars per share) \| $ / shares	$ 21.58			$ 21.58