Summary of Significant Accounting Policies, Recently Adopted Accounting Pronouncements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2017
Recently Adopted/Issued Accounting Pronouncements [Abstract]
Right-of-use asset	$ 127
Lease liability	127
ASU 2016-01 [Member]
Recently Adopted/Issued Accounting Pronouncements [Abstract]
Cumulative-effect adjustment to reclassify unrealized gains on equity securities after tax		$ 0
ASU 2018-11 [Member]
Recently Adopted/Issued Accounting Pronouncements [Abstract]
Right-of-use asset	127
Lease liability	127
ASU 2016-13 [Member] | Minimum [Member]
Recently Adopted/Issued Accounting Pronouncements [Abstract]
Pre-tax cumulative effect adjustment to opening balance of retained earnings	13,000
ASU 2016-13 [Member] | Maximum [Member]
Recently Adopted/Issued Accounting Pronouncements [Abstract]
Pre-tax cumulative effect adjustment to opening balance of retained earnings	$ 18,000
Other Comprehensive Income (Loss) [Member] | ASU 2016-01 [Member]
Recently Adopted/Issued Accounting Pronouncements [Abstract]
Cumulative-effect adjustment to reclassify unrealized gains on equity securities before tax		(71,012)
Cumulative-effect adjustment to reclassify unrealized gains on equity securities after tax		(46,157)
Retained Earnings [Member] | ASU 2016-01 [Member]
Recently Adopted/Issued Accounting Pronouncements [Abstract]
Cumulative-effect adjustment to reclassify unrealized gains on equity securities before tax		71,012
Cumulative-effect adjustment to reclassify unrealized gains on equity securities after tax		$ 46,157