Date: 201911
Local time of day: 0601-1200
Location: DEN.Airport, CO
Light: Daylight
Aircraft: Regional Jet 700 ER/LR (CRJ700)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
ATC / advisory: TRACON D01
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Time Pressure; Training / Qualification; Communication Breakdown; Distraction; Situational Awareness; Workload
Second reporter function: First Officer; Pilot Flying
Anomaly: Deviation - Altitude Undershoot; Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert
Contributing factors: Environment - Non Weather Related; Chart Or Publication; Company Policy; Human Factors
Primary problem: Ambiguous

Narrative: I believe the factors include a very busy flight deck coordinating and loading 2 different arrivals with descend via clearances; especially into DEN which has very specific transitions based on runways. This also includes changing the runway assignment close to the runway specific transition.I also believe the LIDO charts do not depict the mandatory altitudes clearly. A good example is to review the same JEPP chart which breaks out the transitions and uses the word 'MANDATORY' on the chart depiction. It's an easy altitude to miss on the LIDOs especially during a high workload cockpit situations.Another factor is ATC phraseology. When given an approach clearance with an altitude limit the 'cross XXXXX at 9;000 feet; cleared ILS 34R' is used. I understand BFREE is a charted mandatory altitude; but that is not the norm; and is misleading.During the high workload environment of transitioning from a STAR to an ILS while being slowed by ATC my attention was also split to monitoring and providing guidance of aircraft and avionics configurations to a brand new First Officer.An additional factor is SOP briefing guidance for approaches. It only speaks to brief initial approach altitude; GS intercept or FAF crossing altitude and minimums altitude. There is no guidance to brief any mandatory altitudes AFTER the IAF which BFREE was.The last factor is training. We do not train RNAV STAR to RNAV ILS transitions.While descending via the LDORA2 arrival in to DEN we received a new clearance to descend via the TELLR2 arrival. We loaded the new arrival and briefed the all the crossing restrictions and speeds on the new arrival from the runway assigned from TRACON. Somewhere around the THRUU Intersection we were told to change runway assignments from Runway 35L to Runway 34R. We quickly briefed the new runway; loaded new approach speeds; and loaded the new runway in to the FMS. At around NARLE we were told 'cleared for ILS Runway 34R from TELLR.' We completed the RNAV turn onto the inbound course; went to green needles and armed the approach. We then landed without incident. We were told on the ground that there was a potential pilot deviation. After speaking with an air traffic manager we were told that we did not descend to cross BFREE at 10;000 feet; but that we were on profile for the rest of the STAR and ILS.


Second narrative: [Narrative contained no additional information.]


Synopsis: CRJ-700 flight crew reported missing an altitude crossing restriction during approach to DEN airport.