Investments in Debt and Equity Securities

3 Months Ended

Mar. 31, 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 classified as available-for-sale and are carried at market value. Prior to the fourth quarter of 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 added to or deducted from accumulated other comprehensive (deficit) margin. During the fourth quarter of 2017, we began applying regulated operations accounting to the unrealized gains and losses to all investment securities. All realized and unrealized gains and losses are determined using the specific identification method. As of March 31, 2018 approximately 65% 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 March 31, 2018 and December 31, 2017.

		Gross Unrealized
		(dollars in thousands)
March 31, 2018		Cost		Gains		Losses			Fair Value
Equity	$	247,242	$	90,257	$	(5,296	)	$	332,203
Debt		244,492		901		(5,599	)		239,794
Other		12,912		1		—			12,913
Total	$	504,646	$	91,159	$	(10,895	)	$	584,910

		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