Long-Term Debt (Schedule of Boyd Bank Credit Facility) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Line of Credit Facility [Line Items]
Borrowings under Boyd Gaming bank credit facility			$ 223,900	$ 396,100
Loss on early extinguishments of debt	$ 419	$ 30,962	846	31,470
Parent
Line of Credit Facility [Line Items]
Loss on early extinguishments of debt	0	30,008	0	30,008
Bank Credit Facility \| Swing Loan [Member]
Line of Credit Facility [Line Items]
Amount outstanding	6,900		6,900		$ 6,000
Bank Credit Facility \| Parent
Line of Credit Facility [Line Items]
Amount outstanding	903,275		903,275		1,209,725
Bank Credit Facility \| Parent \| Initial Term Loan
Line of Credit Facility [Line Items]
Amount outstanding	177,025		177,025		183,275
Bank Credit Facility \| Parent \| Incremental Term Loan [Member]
Line of Credit Facility [Line Items]
Amount outstanding	726,250		726,250		730,750
Bank Credit Facility \| Parent \| Swing Loan [Member]
Line of Credit Facility [Line Items]
Amount outstanding	0		0		55,700
Bank Credit Facility \| Subsidiary, Peninsula Gaming [Member]
Line of Credit Facility [Line Items]
Amount outstanding	610,525		610,525		$ 662,750
Loss on early extinguishments of debt	$ 400	$ 1,000	$ 800	$ 1,500