Derivative Instruments, Hedging Activities and Accumulated Other Comprehensive Income - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Gains on Cash Flow Hedges
December 31, 2016	$ 11,223
June 30, 2017	9,963
Income Tax Expense
December 31, 2016	(4,435)
June 30, 2017	(3,951)
Accumulated Other Comprehensive Income, net of taxes
December 31, 2016	6,788
June 30, 2017	6,012
Gains on Cash Flow Hedges
Gains on Cash Flow Hedges
Net change in unrealized losses	(1,867)
Amounts reclassified from accumulated other comprehensive income to interest expense	607
Net current period accumulated other comprehensive income (loss)	(1,260)
Income Tax Expense
Net change in unrealized losses	717
Amounts reclassified from accumulated other comprehensive income to interest expense	(233)
Net current period accumulated other comprehensive income (loss)	484
Accumulated Other Comprehensive Income, net of taxes
Net change in unrealized losses	(1,150)
Amounts reclassified from accumulated other comprehensive income to interest expense	374
Net current period accumulated other comprehensive income (loss)	$ (776)