Debt (Maturities of Long-term Debt) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Debt Disclosure [Abstract]
2016	$ 168,314	[1]
2017	140,908
2018	170,960
2019	322,014	[2]
2020	301,072
Thereafter	937,702
Total	$ 2,040,970

[1] Includes the balance of the $125.0 Million Fixed-Rate Loan which was repaid in full on January 4, 2016.

[2] Includes the balance outstanding as of December 31, 2015 of the $500 Million Unsecured 2015 Line of Credit. However, Piedmont may extend the term for up to one additional year (through two available six month extensions to a final extended maturity date of June 18, 2020) provided Piedmont is not then in default and upon payment of extension fees.