Investments in Debt and Equity Securities

6 Months Ended

Jun. 30, 2018

Investments in Debt and Equity Securities

Investments in Debt and Equity Securities

(D)         Investments in Debt and Equity Securities.    Investment securities we hold are carried at market value. Prior to October 1, 2017, unrealized gains and losses of investment securities related to nuclear decommissioning were deferred pursuant to regulated operations accounting, while those for all other investment securities were recorded to accumulated other comprehensive (deficit) margin. During the fourth quarter of 2017, we began applying regulated operations accounting to the unrealized gains and losses for all investment securities. All realized and unrealized gains and losses are determined using the specific identification method. As of June 30, 2018, approximately 66% of these gross unrealized losses had been unrealized for a duration of less than one year.

The following tables summarize debt and equity securities as of June 30, 2018 and December 31, 2017.

		Gross Unrealized
		(dollars in thousands)
June 30, 2018		Cost		Gains		Losses			Fair Value
Equity	$	248,817	$	96,340	$	(4,885	)	$	340,272
Debt		253,860		694		(5,087	)		249,467
Other		8,645		—		—			8,645
Total	$	511,322	$	97,034	$	(9,972	)	$	598,384

		Gross Unrealized
		(dollars in thousands)
December 31, 2017		Cost		Gains		Losses			Fair Value
Equity	$	246,549	$	91,954	$	(4,064	)	$	334,439
Debt		240,878		1,814		(2,262	)		240,430
Other		10,807		1		—			10,808
Total	$	498,234	$	93,769	$	(6,326	)	$	585,677