Derivatives - Interest Rate Swap (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2012	Dec. 19, 2012
Derivative Instruments, Gain (Loss) [Line Items]
First Portion Variable-Rate Debt Outstanding			$ 150,000,000
Derivative, Fixed Interest Rate			2.98%
Notional Amount of Interest Rate Cash Flow Hedge Derivatives	55,000,000
Derivative, Cash Received on Hedge	28,000
Interest rate swap		1,800,000
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Tax		$ (696,000)