Other Assets - Schedule of Changes in Company's Limited Partnership Investments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Equity Method Investment Summarized Financial Information Assets [Roll Forward]
Limited partnership investments	$ 17,401	$ 16,990	$ 15,795	$ 15,795
Capital contributions	327	75	589	368
Pro-rata share in the net income (loss) of limited partnerships	(610)	370	2,993	1,612
Distributions	(2,586)	(701)	(4,845)	(1,041)
Limited partnership investments	$ 14,532	$ 16,734	$ 14,532	$ 16,734

Equity Method Investment Summarized Financial Information Assets [Roll Forward]

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Cash outflow related to the acquisition or continued holding of limited partnership interests held for investment purposes.

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