Fair Value Measurements (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration, liabilities increase (decrease) in fair value	$ 553,000	$ 708,000	$ 0
Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps	(2,252,000)
Contingent consideration	(784,000)	(708,000)
Total liabilities	(3,036,000)
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps	0
Contingent consideration	0	0
Total liabilities	0
Significant Other Observable Inputs (Level 2) | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps	(2,252,000)
Contingent consideration	0	0
Total liabilities	(2,252,000)
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration assets, purchase, sale, issuances and transfers		0
Fair value assets and liabilities, transfers amount	0
Significant Unobservable Inputs (Level 3) | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps	0
Contingent consideration	(784,000)	(708,000)
Total liabilities	(784,000)
Estimate of fair value | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Lines of credit, fair value disclosure	682,100,000	274,600,000
Estimate of fair value | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration, additional consideration expected to be received	553,000
Contingent consideration, liabilities increase (decrease) in fair value	(22,000)
Contingent consideration assets, purchase, sale, issuances and transfers	(455,000)
Contingent consideration	(784,000)	(708,000)
Carrying value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Lines of credit, fair value disclosure	$ 696,900,000	$ 274,600,000