Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Unrealized holding gains (losses) arising during the period, income tax (expense)	$ (963)	$ (10,927)	$ (304)
Reclassification adjustment for (gains) included in net earnings (loss), income tax expense	970	6,816	8,639
Experience gain (loss), income tax (expense) benefit	2,637	(919)	7,219
Reclassification adjustment for amortization of experience (gain) loss recognized as net periodic benefit cost, income tax (expense) benefit	(1,922)	(2,504)	(2,148)
Change in fair market value, income tax (expense)	(145)	(388)	341
Reclassification adjustment for (gains) losses included in net earnings (loss), income tax expense (benefit)	(56)	(225)	(298)
Public Service Company of New Mexico
Unrealized holding gains (losses) arising during the period, income tax (expense)	(963)	(10,927)	(304)
Reclassification adjustment for (gains) included in net earnings (loss), income tax expense	970	6,816	8,639
Experience gain (loss), income tax (expense) benefit	2,637	(919)	7,219
Reclassification adjustment for amortization of experience (gain) loss recognized as net periodic benefit cost, income tax (expense) benefit	$ (1,922)	$ (2,504)	$ (2,148)

Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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