Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income applicable to Piedmont	$ 8,422	$ 8,153	$ 50,208	$ 16,114	$ 10,942	$ 57,830	$ 66,783	$ 84,886
Other comprehensive income/(loss):
Effective portion of gain/(loss) on derivative instruments that are designated and qualify as cash flow hedges (See Note 5)	(1,386)			1,144			(6,874)	4,408
Plus/(less): Reclassification of net loss/(gain) included in net income (See Note 5)	(427)			(434)			(1,871)	373
Other comprehensive income/(loss)	(1,813)	$ (4,137)	$ (2,795)	710	$ 1,502	$ 2,569	(8,745)	4,781
Comprehensive income applicable to Piedmont	$ 6,609			$ 16,824			$ 58,038	$ 89,667