Organization and Basis of Presentation - Summary of Financial Securities (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Equity securities:
Gross Unrealized Gain (Loss)	$ (1,073)	$ 4,454
Carrying Value	2,700		$ 3,600
Held to maturity
Equity and Debt Securities, Amortized Cost	152,232		140,649
Equity and Debt Securities, Gross Unrealized Gain (Loss)	2,201		3,544
Equity and Debt Securities, Marketable Securities	154,433		144,193
Equity and Debt Securities, Allowance for Credit Loss	13,644		0
Investment funds - debt securities
Equity securities:
Amortized Cost/Cost	28,153		29,588
Gross Unrealized Gain (Loss)	721		544
Carrying Value	28,874		30,132
Common stock and stock funds
Equity securities:
Amortized Cost/Cost	45,518		34,941
Gross Unrealized Gain (Loss)	1,677		2,927
Carrying Value	47,195		37,868
U.S. treasury securities
Available for sale
Amortized Cost/Cost			2,421
Gross Unrealized Gain (Loss)			13
Carrying Value			2,434
Investment-grade unsecured debt
Available for sale
Amortized Cost/Cost	1,050		1,048
Gross Unrealized Gain (Loss)	(197)		60
Carrying Value	853		1,108
Allowance for Credit Losses	0
Mortgage backed securities
Held to maturity
Amortized Cost/Cost	77,511		72,651
Gross Unrealized Gain (Loss)	0		0
Carrying Value	77,511		$ 72,651
Allowance for Credit Losses	$ 13,644

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