Debt (Narrative) (Details) (USD $)	12 Months Ended				12 Months Ended		12 Months Ended			12 Months Ended			12 Months Ended					12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jun. 28, 2013	Dec. 31, 2013 Debt Instrument, Name, Revolving Credit Facility [Member]	Jun. 28, 2013 Debt Instrument, Name, Revolving Credit Facility [Member]	Dec. 31, 2013 Debt Instrument, Name, 7 Year Term Loan [Member]	Dec. 31, 2013 Debt Instrument, Name, 7 Year Term Loans (A) & (B) [Member]	Jun. 28, 2013 Debt Instrument, Name, 7 Year Term Loans (A) & (B) [Member]	Dec. 31, 2013 Debt Instrument, Name, 4.5 Year Term Loan [Member]	Dec. 31, 2013 Debt Instrument, Name, Fannie Mae (A) [Member]	Dec. 31, 2013 Debt Instrument, Name, Fannie Mae (B) [Member]	Dec. 31, 2013 Debt Instrument, Name, Key Bank [Member]	Aug. 30, 2013 Debt Instrument, Name, Key Bank [Member]	Jun. 28, 2013 Debt Instrument, Name, 7 Year Term Loan (A) [Member]	Jun. 28, 2013 Debt Instrument, Name, 7 Year Term Loan (B) [Member]	May 01, 2012 Line of Credit Facility, 2012 Modification [Member]	Dec. 31, 2013 Interest Rate Swap, Maturity Date April 2019 [Member]	Dec. 31, 2013 Interest Rate Swap, Maturity Date June 2020 [Member]	Dec. 31, 2013 Spread Over LIBOR Prior To Adjustment [Member] Debt Instrument, Name, Revolving Credit Facility [Member]	Dec. 31, 2013 Spread Over LIBOR Prior To Adjustment [Member] Debt Instrument, Name, 7 Year Term Loans (A) & (B) [Member]	Dec. 31, 2013 Spread Over LIBOR After Adjustment [Member] Debt Instrument, Name, Revolving Credit Facility [Member]	Dec. 31, 2013 Spread Over LIBOR After Adjustment [Member] Debt Instrument, Name, 7 Year Term Loans (A) & (B) [Member]
Line of Credit Facility, Maximum Borrowing Capacity				$ 370,000,000													$ 320,000,000
Long-term Debt	80,080,000	0									71,090,000	7,234,000
Debt Instrument, Interest Rate, Stated Percentage											6.85%	7.17%
Amortization of loan costs	706,000	320,000	581,000
Write-off of debt issuance costs	416,000	0	0
Term Loans, Outstanding Balance									120,000,000	250,000,000					80,000,000	40,000,000
Debt Maturity, Years					5 years 0 months 0 days			7 years 0 months 0 days
Debt Maturity, Extension Option, Number Of Years					1 year 0 months 0 days
Credit Facility, Current Revolving Borrowing Capacity						250,000,000
Number of basis points over LIBOR	17
Debt Instrument, Basis Spread on Variable Rate										17500.00%			30000.00%							14000.00%	15000.00%	16500.00%	17500.00%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum					19000.00%		20000.00%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	3500.00%
Credit Facility Expansion Amount						130,000,000
Unused balance of the unsecured revolving credit facility					83,000,000
Bank term loans - secured	0	19,250,000												19,250,000
Derivative, Fixed Interest Rate																		3.29%	3.86%
Derivative, Description of Variable Rate Basis																		1-month LIBOR	1-month LIBOR
Derivative, Basis Spread on Variable Rate																		1.75%	1.75%
Derivative, Notional Amount																		40,000,000	80,000,000
Interest Rate Cash Flow Hedge Asset at Fair Value																		544,000
Interest Rate Cash Flow Hedge Liability at Fair Value																			$ 431,000