Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income applicable to Piedmont	$ 10,942	$ 23,710	$ 68,772	$ 38,814
Other comprehensive income:
Effective portion of gain/(loss) on derivative instruments that are designated and qualify as cash flow hedges (See Note 6)	1,747	(911)	3,264	132
Plus: Reclassification of net (gain)/loss included in net income (See Note 6)	(245)	977	807	2,283
Gain on investment in available for sale securities	0	15	0	28
Other comprehensive income	1,502	81	4,071	2,443
Comprehensive income applicable to Piedmont	$ 12,444	$ 23,791	$ 72,843	$ 41,257

Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax 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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