Indebtedness - Schedule of Debt (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Secured debt	$ 360,671	$ 277,742
Unamortized fair value adjustments	(1,442)	3
Indebtedness	359,229	277,745
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Secured debt	59,000	70,000
Stated Maturity Date	May 13, 2016
Revolving Credit Facility [Member] | LIBOR [Member] | Minimum [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.60%
Revolving Credit Facility [Member] | LIBOR [Member] | Maximum [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.20%
North Point Center [Member] | Note 5 [Member]
Debt Instrument [Line Items]
Secured debt	685	705
Stated Maturity Date	Feb. 01, 2017
North Point Center [Member] | Note 5 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.00%
North Point Center [Member] | Notes 1 [Member]
Debt Instrument [Line Items]
Secured debt	10,149	10,319
Stated Interest Rate	6.45%
Stated Maturity Date	Feb. 05, 2019
North Point Center [Member] | Notes 2 [Member]
Debt Instrument [Line Items]
Secured debt	2,753	2,830
Stated Interest Rate	7.25%
Stated Maturity Date	Sep. 15, 2025
North Point Center [Member] | Note 4 [Member]
Debt Instrument [Line Items]
Secured debt		1,030
Oyster Point [Member]
Debt Instrument [Line Items]
Secured debt	6,274	6,466
Stated Interest Rate	5.41%
Stated Maturity Date	Dec. 01, 2015
249 Central Park Retail [Member]
Debt Instrument [Line Items]
Secured debt	15,566	15,834
Stated Interest Rate	5.99%
Stated Maturity Date	Sep. 08, 2016
South Retail [Member]
Debt Instrument [Line Items]
Secured debt	6,867	6,985
Stated Interest Rate	5.99%
Stated Maturity Date	Sep. 08, 2016
Studio 56 Retail [Member]
Debt Instrument [Line Items]
Secured debt	2,618	2,690
Stated Interest Rate	3.75%
Stated Maturity Date	May 07, 2015
Commerce Street Retail [Member]
Debt Instrument [Line Items]
Secured debt	5,549	5,613
Stated Maturity Date	Oct. 31, 2018
Commerce Street Retail [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.25%
Fountain Plaza Retail [Member]
Debt Instrument [Line Items]
Secured debt	7,783	7,917
Stated Interest Rate	5.99%
Stated Maturity Date	Sep. 08, 2016
Dick's at Town Center [Member]
Debt Instrument [Line Items]
Secured debt	8,216	8,318
Stated Maturity Date	Oct. 31, 2017
Dick's at Town Center [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.75%
Broad Creek Shopping Center [Member] | Notes 1 [Member]
Debt Instrument [Line Items]
Secured debt	4,452	4,503
Stated Maturity Date	Oct. 31, 2018
Broad Creek Shopping Center [Member] | Notes 1 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.25%
Broad Creek Shopping Center [Member] | Notes 2 [Member]
Debt Instrument [Line Items]
Secured debt	8,173	8,267
Stated Maturity Date	Oct. 31, 2018
Broad Creek Shopping Center [Member] | Notes 2 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.25%
Broad Creek Shopping Center [Member] | Notes 3 [Member]
Debt Instrument [Line Items]
Secured debt	3,422	3,461
Stated Maturity Date	Oct. 31, 2018
Broad Creek Shopping Center [Member] | Notes 3 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.25%
Hanbury Village [Member] | Notes 1 [Member]
Debt Instrument [Line Items]
Secured debt	21,218	21,449
Stated Interest Rate	6.67%
Stated Maturity Date	Oct. 11, 2017
Hanbury Village [Member] | Notes 2 [Member]
Debt Instrument [Line Items]
Secured debt	4,090	4,159
Stated Maturity Date	Oct. 31, 2018
Hanbury Village [Member] | Notes 2 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.25%
Harrisonburg Regal [Member]
Debt Instrument [Line Items]
Secured debt	3,659	3,842
Stated Interest Rate	6.06%
Stated Maturity Date	Jun. 08, 2017
Tyre Neck Harris Teeter [Member]
Debt Instrument [Line Items]
Secured debt	2,437	2,482
Stated Maturity Date	Oct. 31, 2018
Tyre Neck Harris Teeter [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.25%
The Cosmopolitan [Member]
Debt Instrument [Line Items]
Secured debt	47,132	47,723
Stated Interest Rate	3.75%
Stated Maturity Date	Jul. 01, 2051
Smith's Landing [Member]
Debt Instrument [Line Items]
Secured debt	24,470	24,795
Stated Maturity Date	Jan. 31, 2017
Smith's Landing [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	2.15%
Liberty Apartments [Member]
Debt Instrument [Line Items]
Secured debt	20,603
Stated Interest Rate	5.66%
Stated Maturity Date	Nov. 01, 2043
4525 Main Street [Member]
Debt Instrument [Line Items]
Secured debt	30,870	11,313
Stated Maturity Date	Jan. 30, 2017
4525 Main Street [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.95%
Encore Apartments [Member]
Debt Instrument [Line Items]
Secured debt	22,215	3,585
Stated Maturity Date	Jan. 30, 2017
Encore Apartments [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.95%
Whetstone Apartments [Member]
Debt Instrument [Line Items]
Secured debt	16,019	284
Stated Maturity Date	Oct. 08, 2016
Whetstone Apartments [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.90%
Sandbridge Commons [Member]
Debt Instrument [Line Items]
Secured debt	5,892	3,172
Stated Maturity Date	Jan. 17, 2018
Sandbridge Commons [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.85%
Oceaneering [Member]
Debt Instrument [Line Items]
Secured debt	13,490
Stated Maturity Date	Feb. 28, 2018
Oceaneering [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.75%
Commonwealth of Virginia [Member] | Chesapeake [Member]
Debt Instrument [Line Items]
Secured debt	3,585
Stated Maturity Date	Aug. 28, 2017
Commonwealth of Virginia [Member] | Chesapeake [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.90%
Lightfoot Marketplace [Member]
Debt Instrument [Line Items]
Secured debt	$ 3,484
Stated Maturity Date	Nov. 14, 2017
Lightfoot Marketplace [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Stated interest rate, basis spread on variable rate	1.90%